CN105817245A - Nanometer carbon material containing heteroatoms and preparation method and application thereof, and dehydrogenation reaction method for hydrocarbons - Google Patents

Abstract

The invention discloses a nanometer carbon material containing heteroatoms and a preparation method and application thereof. The nanometer carbon material containing heteroatoms comprises, by weight, 4 to 12% of elemental O, 2 to 16% of elemental N and 82 to 94% of elemental C. In a pattern of X-ray photoelectron spectroscopy, a ratio of the amount of elemental O determined by peaks in a range of 531.0 to 532.5 eV to the amount of elemental O determined by peaks in a range of 532.6 to 533.5 eV is 0.1 to 0.5; and a ratio of the amount of elemental N determined by peaks in a range of 398.5 to 400.1 eV to the amount of the total elemental N is 0.8 to 1. The invention also provides a method for a dehydrogenation reaction of hydrocarbons with the nanometer carbon material containing heteroatoms as a catalyst. The nanometer carbon material containing heteroatoms shows good catalytic performance in the dehydrogenation reaction of hydrocarbons and can obviously improve the conversion rate of raw materials and product selectivity.

Description

A heteroatom-containing nano-carbon material, its preparation method and application, and a hydrocarbon dehydrogenation reaction method

technical field

The present invention relates to a kind of heteroatom-containing nano-carbon material, and the present invention also relates to a preparation method of a heteroatom-containing nano-carbon material and the heteroatom-containing nano-carbon material prepared by the method. The heteroatom-containing nano-carbon material prepared by roasting the heteroatom-containing nano-carbon material. The present invention further relates to the application of the heteroatom-containing nano-carbon material as a catalyst for hydrocarbon dehydrogenation reaction and a method for hydrocarbon dehydrogenation reaction.

Background technique

The dehydrogenation reaction of hydrocarbons is an important type of reaction. For example, most low-carbon alkenes are obtained through the dehydrogenation reaction of low-carbon alkanes. Dehydrogenation reactions can be divided into direct dehydrogenation reactions (ie, no oxygen participation) and oxidative dehydrogenation reactions (ie, oxygen participation) according to whether oxygen is involved.

Various types of carbon nanomaterials have been proven to have catalytic effects on both direct dehydrogenation and oxidative dehydrogenation reactions of hydrocarbons, and the introduction of oxygen atoms and/or nitrogen atoms into carbon nanomaterials can improve their catalytic activity.

The introduction of oxygen atoms into carbon nanomaterials can form oxygen-containing functional groups such as hydroxyl groups, carbonyl groups, carboxyl groups, ester groups, and acid anhydrides on the surface of carbon nanomaterials.

Oxygen atoms can be introduced into the nano-carbon material by oxidizing the nano-carbon material, thereby increasing the content of oxygen-containing functional groups in the nano-carbon material. For example, carbon nanomaterials can be subjected to reflux reaction in strong acid (such as HNO ₃ , H ₂ SO ₄ ) and/or strong oxidizing solution (such as H ₂ O ₂ , KMnO ₄ ), and can also assist in the reflux reaction. Microwave heating or ultrasonic vibration to enhance the effect of oxidation reaction. However, the reflux reaction in a strong acid and/or strong oxidizing solution may have adverse effects on, or even destroy, the skeleton structure of the carbon nanomaterials. For example: reflux reaction of carbon nanomaterials in nitric acid, although a large number of oxygen-containing functional groups can be introduced on the surface of carbon nanomaterials, it is very easy to cause the carbon nanomaterials to be cut off and/or significantly increase the defect sites in the graphite network structure, thereby reducing Properties of carbon nanomaterials, such as thermal stability. In addition, when oxygen atoms are introduced by carrying out reflux reaction in a strong acid and/or strong oxidizing solution, the amount of oxygen atoms introduced has a high dependence on the reaction operating conditions, and the fluctuation range is wide.

When nitrogen atoms are introduced into nanocarbon materials, nitrogen atoms are usually divided into chemical nitrogen and structural nitrogen according to the different chemical environments of nitrogen atoms in nanocarbon materials. Chemical nitrogen mainly appears on the surface of materials in the form of surface functional groups, such as surface nitrogen-containing functional groups such as amino groups or nitrosyl groups. Structural nitrogen refers to nitrogen atoms that enter the skeleton structure of nanocarbon materials and bond with carbon atoms. Structural nitrogen mainly includes graphitic nitrogen (i.e., ), pyridinic nitrogen (ie, ) and pyrrole nitrogen (ie, ). Graphite nitrogen directly replaces carbon atoms in the graphite lattice to form saturated nitrogen atoms; pyridine nitrogen and pyrrole nitrogen are unsaturated nitrogen atoms, which often cause the absence of adjacent carbon atoms and form defect sites when replacing carbon atoms.

By introducing a nitrogen-containing functional atmosphere (such as ammonia, nitrogen, urea, melamine) during the synthesis of nano-carbon materials, nitrogen can be simultaneously introduced into nano-carbons during the synthesis of nano-carbon materials using high temperature and/or high pressure. In the skeleton structure and/or surface of the material; it is also possible to introduce nitrogen into the nanometer carbon material by using high temperature and/or high pressure in a nitrogen-containing functional atmosphere (such as ammonia, nitrogen, urea, melamine). surface of the carbon material. Although high temperature and/or high pressure can form structural nitrogen in carbon nanomaterials, the type of nitrogen-containing species depends on the reaction conditions and is not easy to control; moreover, the different types of nitrogen-containing species thus produced are unevenly distributed on the surface of carbon nanomaterials , resulting in unstable properties of nitrogen-containing carbon nanomaterials. Nitrogen atoms can also be introduced on the surface of the carbon nanomaterials by oxidizing the carbon nanomaterials and then reacting with amines. The nitrogen atoms introduced in this way are basically chemical nitrogen.

Although a lot of progress has been made in the research on the doping modification of carbon nanomaterials and their catalytic properties, there is still no consensus on some of the basic issues. Do in-depth research.

Contents of the invention

An object of the present invention is to provide a method for preparing heteroatom-containing nano-carbon materials, which can not only introduce heteroatoms on the surface of nano-carbon materials, but also has little influence on the structure of nano-carbon materials. Another object of the present invention is to provide a heteroatom-containing nano-carbon material. When the heteroatom-containing nano-carbon material is used in the dehydrogenation reaction of hydrocarbons, it can not only obtain a higher conversion rate of raw materials, but also obtain a higher product selectivity. Another object of the present invention is to provide a hydrocarbon dehydrogenation reaction method, which can obtain higher raw material conversion rate and product selectivity.

According to the first aspect of the present invention, the present invention provides a heteroatom-containing nano-carbon material, the heteroatom-containing nano-carbon material contains C elements, O elements and N elements, and the total amount of the heteroatom-containing nano-carbon material As a benchmark and in terms of elements, the content of O element is 4-12% by weight, the content of N element is 2-6% by weight, and the content of C element is 82-94% by weight;

In this heteroatom-containing nano-carbon material, the amount of O element determined by the peak in the X-ray photoelectron spectrum in the range of 531.0-532.5eV is I _O ^c , and by the peak in the X-ray photoelectron spectrum in the range of 532.6-533.5eV The determined amount of O element is I _O ^e , and I _O ^c /I _O ^e is in the range of 0.5-1;

In the heteroatom-containing nano-carbon material, the total amount of N elements in the heteroatom-containing nano-carbon material is determined by X-ray photoelectron spectroscopy to be I _N ^t , and the peak in the range of 398.5-400.1eV in the X-ray photoelectron spectroscopy The determined amount of N element is I _N ^c , and I _N ^c /I _N ^t is in the range of 0.8-1.

According to a second aspect of the present invention, the present invention provides a method for preparing a heteroatom-containing nano-carbon material, the method comprising distributing a raw material nano-carbon material, at least one nitrogen-containing compound, and at least one peroxide The aqueous dispersion of the compound is reacted in a closed container, and the nitrogen-containing compound is selected from NH ₃ , hydrazine and urea. During the reaction, the temperature of the aqueous dispersion is kept within the range of 80-220°C.

According to the third aspect of the present invention, the present invention provides a heteroatom-containing nano-carbon material prepared by the method according to the second aspect of the present invention.

According to the fourth aspect of the present invention, the present invention provides a heteroatom-containing nano-carbon material, which is the heteroatom-containing nano-carbon material according to the first aspect or the third aspect of the present invention Made by roasting.

According to the fifth aspect of the present invention, the present invention provides the heteroatom-containing nano-carbon material according to the first aspect of the present invention, the heteroatom-containing nano-carbon material according to the third aspect of the present invention, or the fourth aspect of the present invention Application of heteroatom-containing nanocarbon materials as catalysts for hydrocarbon dehydrogenation reactions.

According to the sixth aspect of the present invention, the present invention provides a hydrocarbon dehydrogenation reaction method, the method comprising the presence or absence of oxygen, under the hydrocarbon dehydrogenation reaction conditions, the hydrocarbon and the first The heteroatom-containing nano-carbon material according to the first aspect, the heteroatom-containing nano-carbon material according to the third aspect of the present invention, or the heteroatom-containing nano-carbon material according to the fourth aspect of the present invention.

According to the preparation method of the heteroatom-containing nano-carbon material of the present invention, it can not only stably regulate and/or increase the heteroatom content in the nano-carbon material, but also has little influence on the structure of the nano-carbon material itself, and the prepared heteroatom-containing nano-carbon material With stable performance. The heteroatom-containing nano-carbon material according to the invention shows good catalytic performance in the dehydrogenation reaction of hydrocarbon substances, and can obviously improve the conversion rate of raw materials and the selectivity of products.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, together with the following specific embodiments, are used to explain the present invention, but do not constitute a limitation to the present invention.

FIG. 1 is a transmission electron micrograph of the heteroatom-containing nanocarbon material prepared in Example 1.

FIG. 2 is a transmission electron micrograph of the raw carbon nanomaterial used in Example 1. FIG.

detailed description

In the present invention, nano-carbon material refers to a carbon material with at least one dimension of the dispersed phase smaller than 100 nm.

According to the first aspect of the present invention, the present invention provides a heteroatom-containing nano-carbon material, which contains C element, O element and N element.

According to the heteroatom-containing nano-carbon material of the present invention, based on the total amount of the heteroatom-containing nano-carbon material and in terms of elements, the content of O element is 4-12% by weight, preferably 4-10% by weight, more preferably 5-9% by weight, more preferably 5.5-8% by weight; the content of N element is 2-6% by weight, preferably 2.2-5.8% by weight, more preferably 2.5-5% by weight, further preferably 3-4.5% by weight % by weight; the content of element C is 82-94% by weight, preferably 84.2-93.8% by weight, more preferably 86-92.5% by weight, further preferably 87.5-91.5% by weight. Among them, the content of each element is determined by X-ray photoelectron spectroscopy (XPS), and the content of the element is determined by the area corresponding to the 1s electron spectrum peak; the sample is placed in a helium atmosphere at a temperature of 150 ° C and 1 standard atmospheric pressure before testing. Let dry for 3 hours.

In the present invention, X-ray photoelectron spectrum analysis is tested on the ESCALab250 type X-ray photoelectron spectrometer equipped with ThermoAvantageV5.926 software of ThermoScientific Company, and the excitation source is monochromatic AlKα X-ray, energy is 1486.6eV, and power is 150W , the penetration energy used for the narrow scan is 30eV, the basic vacuum during the analysis and test is 6.5×10 ^-10 mbar, the electron binding energy is corrected by the C1s peak (284.0eV) of elemental carbon, and the data processing is carried out on the ThermoAvantage software, in the analysis module The sensitivity factor method was used for quantitative analysis.

According to the heteroatom-containing nano-carbon material of the present invention, the amount of the O element (that is, C=O) determined by the peak in the X-ray photoelectron spectrum in the range of 531.0-532.5eV is I _O ^c , and by the X-ray photoelectron spectrum The amount of O element (that is, CO) determined by the peak in the 532.6-533.5eV range is I _O ^e , and I _O ^c /I _O ^e is in the range of 0.5-1, preferably in the range of 0.5-0.95, more Preferably in the range of 0.6-0.8. In the present invention, the total amount of O element is determined by the area A _O ^of the O1s spectrum peak in the X-ray photoelectron spectrum, and the O1s spectrum peak in the X-ray photoelectron spectrum is divided into two groups of peaks, namely in the range of 531.0-532.5eV within the spectrum peak (corresponding to C=O species) and the spectrum peak in the range of 532.6-533.5eV (corresponding to CO species), the area of the spectrum peak in the range of 531.0-532.5eV is recorded as A _O ² , and The area of the spectral peak within the range of 532.6-533.5 eV is recorded as A _O ³ , and I _O ^c /I _O ^e =A _O ² /A _O ³ . In the present invention, when expressing a numerical range, "within the range of x-x" includes both boundary numerical values.

According to the heteroatom-containing nano-carbon material of the present invention, based on the total amount of C element in the heteroatom-containing nano-carbon material, the C element determined by the peak in the X-ray photoelectron spectrum within the range of 284.7-284.9eV (that is, The content of graphitic carbon) can be 70-92% by weight, preferably 75-85% by weight; the total content of C elements determined by the peak in the 286.0-288.8eV range in the X-ray photoelectron spectrum can be 8-30% by weight %, preferably 15-25% by weight. In the present invention, the total amount ^of _C element is determined by the area AC of the C1s spectrum peak in the X-ray photoelectron spectrum, and the C1s spectrum peak in the X-ray photoelectron spectrum is divided into two groups of peaks, namely in the range of 284.7-284.9eV The peaks within (corresponding to graphitic carbon species) and the peaks in the range of 286.0-288.8eV (corresponding to non-graphitic carbon species), the area of the peak in the range of 284.7-284.9eV is recorded as A _C ^2. The area of the spectrum peak in the range of 286.0-288.8eV is recorded as A _C ³ , and the content of C element determined by the peak in the range of 284.7-284.9eV in the X-ray photoelectron spectrum = A _C ² /A _C ¹ , the total content of C elements determined from the peaks in the range of 286.0-288.8 eV in the X-ray photoelectron spectrum = A _C ³ /A _C ¹ .

According to the heteroatom-containing nano-carbon material of the present invention, in the heteroatom-containing nano-carbon material, the amount of C element determined by the peak in the range of 288.6-288.8eV in the X-ray photoelectron energy spectrum is I _C ^c , which is determined by the X-ray photoelectron energy spectrum. The amount of C element determined by the peak in the range of 286.0-286.2eV in the energy spectrum is I _C ^e , and I _C ^c /I _C ^e is in the range of 0.3-1, preferably in the range of 0.4-0.95, more preferably in the range of 0.5 in the range of -0.8. In the present invention, the spectral peaks in the 286.0-288.8eV range (corresponding to non-graphitic carbon species) in the X-ray photoelectron energy spectrum are further divided into two groups of peaks, that is, the spectral peaks in the 286.0-286.2eV range (corresponding to Hydroxyl and ether carbon species) and peaks in the range of 288.6-288.8eV (corresponding to carboxyl, anhydride and ester carbon species), the area of the peak in the range of 286.0-286.2eV is recorded as A _C ⁴ , The area of the spectral peak in the range of 288.6-288.8 eV is recorded as AC ⁵ , and I _C ^c /I _C ^e =A _C ⁵ / _{A C 4} ^.

According to the heteroatom-containing nano-carbon material of the present invention, the total amount of N elements in the heteroatom-containing nano-carbon material is determined to be I _N ^t by X-ray photoelectron spectroscopy, and is within the range of 398.5-400.1eV The amount of N element determined by the peak is I _N ^c , and I _N ^c /I _N ^t is in the range of 0.8-1, preferably in the range of 0.8-0.95. According to the heteroatom-containing nano-carbon material of the present invention, the content of N element (ie, graphitic nitrogen) determined by the peak in the range of 400.6-401.5 eV in the X-ray photoelectron spectrum is low or even not contained. Generally, in the heteroatom-containing nanocarbon material according to the present invention, the amount of N element determined by the peak in the X-ray photoelectron spectrum in the range of 400.6-401.5eV is I _N ^g , and I _N ^g /I _N ^t is not Higher than 0.2, generally in the range of 0-0.2, preferably in the range of 0.05-0.2.

In the present invention, the total amount A _N ¹ of the N element is determined by the area of the N1s spectrum peak in the X-ray photoelectron spectrum, and the N1s spectrum peak in the X-ray photoelectron spectrum is divided into two groups of peaks, namely in the range of 400.6-401.5eV The peaks in the spectrum (corresponding to graphite-type nitrogen species) and the spectrum peaks in the range of 398.5-400.1eV (nitrogen species other than graphite-type nitrogen), to determine the respective areas of these two groups of peaks, will be in the range of 400.6-401.5eV The area of the spectral peak is recorded as A _N ² , and the area of the spectral peak in the range of 398.5-400.1eV is recorded as A _N ³ , I _N ^c /I _N ^t = A _N ³ /A _N ¹ , I _N ^g / I _N ^t =A _N ² /A _N ¹ , when the obtained ratio is less than 0.01, it is considered that this type of species does not exist, and the content of this type of species is recorded as 0.

In the present invention, the position of each peak is determined by the binding energy corresponding to the peak top of the peak, and the peak determined by the above-mentioned range refers to the peak corresponding to the peak top within the range of binding energy, within this range One peak may be included, or two or more peaks may be included. For example: the peaks in the range of 398.5-400.1 eV refer to all peaks corresponding to the peak tops with binding energies in the range of 398.5-400.1 eV.

The heteroatom-containing nanocarbon material according to the present invention can exist in various common forms, specifically, but not limited to, heteroatom-containing carbon nanotubes, heteroatom-containing graphene, heteroatom-containing thin-layer graphite, heteroatom-containing nanocarbon Particles, heteroatom-containing nano-carbon fiber, heteroatom-containing nano-diamond and heteroatom-containing fullerene or a combination of two or more. The heteroatom-containing carbon nanotubes may be one or a combination of two or more of heteroatom-containing single-wall carbon nanotubes, heteroatom-containing double-wall carbon nanotubes, and heteroatom-containing multi-wall carbon nanotubes. The heteroatom-containing nanocarbon material according to the present invention is preferably a heteroatom-containing multi-walled carbon nanotube.

According to the heteroatom-containing nanocarbon material of the present invention, preferably, the specific surface area of the heteroatom-containing multi-walled carbon nanotube is 50-500m ² /g, which can further improve the catalytic performance of the heteroatom-containing nanocarbon material, Especially as a catalyst for the dehydrogenation of hydrocarbons. The specific surface area of the heteroatom-containing multi-walled carbon nanotube is more preferably 80-300m ² /g, still more preferably 90-200m ² /g, still more preferably 100-150m ² /g. In the present invention, the specific surface area is measured by the nitrogen adsorption BET method.

According to the heteroatom-containing nano-carbon material of the present invention, the weight loss rate of the heteroatom-containing multi-walled carbon nanotubes in the temperature range of 400-800°C is w ₈₀₀ , and the weight loss rate in the temperature range of 400-500°C is w ₅₀₀ , w ₅₀₀ /w ₈₀₀ is preferably in the range of 0.01-0.5, so that better catalytic effect can be obtained, especially when used as a catalyst for the dehydrogenation reaction of hydrocarbons, better catalytic effect can be obtained. More preferably, the heteroatom-containing multi-walled carbon nanotubes have a weight loss rate of w ₈₀₀ in the temperature range of 400-800°C, and a weight loss rate of w ₅₀₀ in the temperature range of 400-500°C, w ₅₀₀ /w ₈₀₀ is more preferably in the range of 0.02-0.2. In the present invention, w ₈₀₀ =W ₈₀₀ -W ₄₀₀ , w ₅₀₀ =W ₅₀₀ -W ₄₀₀ , W ₄₀₀ is the mass loss rate measured at a temperature of 400°C, and W ₈₀₀ is the mass loss measured at a temperature of 800°C rate, W ₅₀₀ is the mass loss rate measured at a temperature of 500°C; the weight loss rate is measured in an air atmosphere using a thermogravimetric analyzer, the test starting temperature is 25°C, and the heating rate is 10°C/min; Dry in a helium atmosphere at a temperature of 150°C and 1 standard atmosphere for 3 hours before testing.

In a preferred embodiment of the present invention, the heteroatom-containing nanocarbon material is preferably a heteroatom-containing multi-wall carbon nanotube, and the specific surface area of the heteroatom-containing multi-wall carbon nanotube is 50-500m ² /g , preferably 80-300m ² /g, more preferably 90-200m ² /g, further preferably 100-150m ² /g; and, w ₅₀₀ /w ₈₀₀ is in the range of 0.01-0.5, preferably 0.02-0.2 In the range.

According to the heteroatom-containing nano-carbon material of the present invention, the content of other non-metallic heteroatoms such as sulfur atoms and phosphorus atoms can be a conventional content. Generally, in the heteroatom-containing nano-carbon material according to the present invention, the total amount of other non-metallic heteroatoms (such as sulfur atoms and phosphorus atoms) except oxygen atoms and nitrogen atoms can be 0.5% by weight or less, preferably 0.2% by weight %the following. According to the heteroatom-containing nano-carbon material of the present invention, it can also contain a small amount of residual metal atoms in the preparation process of the nano-carbon material. These residual metal atoms usually originate from the catalyst used when preparing the nano-carbon material. The residual metal atoms The content is generally 0.5% by weight or less, preferably 0.2% by weight or less.

According to a second aspect of the present invention, the present invention provides a method for preparing a heteroatom-containing nano-carbon material, the method comprising distributing a raw material nano-carbon material, at least one nitrogen-containing compound and at least one peroxide The aqueous dispersion of the compound was reacted in a closed container. In the present invention, "at least one kind" means one kind or two or more kinds.

The nitrogen-containing compound is selected from NH ₃ , hydrazine and urea.

The peroxide refers to a compound containing -O-O- bonds in its molecular structure. Specifically, the peroxide can be selected from organic peroxides shown in hydrogen peroxide and formula I,

In formula I, R ₁ and R ₂ are each selected from H, C ₄ -C ₁₂ alkyl, C ₆ -C ₁₂ aryl, C ₇ -C ₁₂ aralkyl, and And R ₁ and R ₂ are not H at the same time, and R ₃ is a C ₄ -C ₁₂ linear or branched chain alkyl group or a C ₆ -C ₁₂ aryl group.

In the present invention, specific examples of C ₄ -C ₁₂ alkyl groups may include, but are not limited to, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, isopentyl, tert-pentyl Base, hexyl (including various isomers of hexyl), cyclohexyl, octyl (including various isomers of octyl), nonyl (including various isomers of nonyl), decyl (including various isomers of undecyl), undecyl (including various isomers of undecyl) and dodecyl (including various isomers of dodecyl).

In the present invention, specific examples of the C ₆ -C ₁₂ aryl group may include, but are not limited to, phenyl, naphthyl, methylphenyl, and ethylphenyl.

In the present invention, specific examples of C ₇ -C ₁₂ aralkyl groups may include, but are not limited to, phenylmethyl, phenylethyl, phenyl-n-propyl, phenyl-n-butyl, phenyl-tert-butyl, phenyl phenyl isopropyl, phenyl n-pentyl and phenyl n-butyl.

Specific examples of the peroxide may include, but are not limited to: hydrogen peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, ethylbenzene hydroperoxide, cyclohexyl hydroperoxide, dicumyl peroxide , dibenzoyl peroxide, di-tert-butyl peroxide and lauryl peroxide.

According to the method of the present invention, the type of peroxide can be optimized according to the type of nitrogen-containing compound. In a preferred embodiment, the nitrogen-containing compound is NH ₃ , and the peroxide is selected from hydrogen peroxide. In another preferred embodiment, the nitrogen-containing compound is hydrazine, and the peroxide is selected from t-butyl hydroperoxide. In yet another preferred embodiment, the nitrogen-containing compound is urea, and the peroxide is selected from cumene hydroperoxide.

According to the method of the present invention, the amount of the nitrogen-containing compound and the peroxide can be selected according to the content and type of nitrogen and oxygen elements expected to be introduced into the raw nano-carbon material. When the heteroatom-containing nano-carbon material finally prepared is used as a catalyst for hydrocarbon dehydrogenation, preferably, the weight ratio of raw material nano-carbon material: nitrogen-containing compound: peroxide is 1:0.01-10:0.01-10, The heteroatom-containing nano-carbon material thus prepared can obtain further improved catalytic effect when used as a catalyst for hydrocarbon dehydrogenation reaction. More preferably, the weight ratio of raw material nano-carbon material: nitrogen-containing compound: peroxide is 1:0.05-3:0.02-5. Further preferably, the weight ratio of raw material nano-carbon material: nitrogen-containing compound: peroxide is 1:0.1-0.5:0.1-1.

According to the method of the present invention, the molar ratio of the nitrogen-containing compound to the peroxide is preferably 1:0.001-10, and the distribution of heteroatoms on the surface of the nano-carbon material in the heteroatom-containing carbon material prepared thereby is more favorable. Even, it also has more excellent catalytic activity when used as a catalyst for hydrocarbon dehydrogenation reaction. The molar ratio of the nitrogen-containing compound to the peroxide is more preferably 1:0.002-5, further preferably 1:0.05-2.

According to the method of the present invention, the amount of water used can be selected according to the amount of raw carbon nanomaterials. Preferably, the weight ratio of raw material nano-carbon material: H ₂ O is 1:2-500. When the amount of water is within this range, the structure and shape of nano-carbon material during processing is better, for example: raw material When the nanocarbon material is a carbon nanotube, it is hardly cut off during processing. The weight ratio of raw material nano-carbon material:H ₂ O is more preferably 1:5-250, further preferably 1:15-50. In addition, the amount of water used can also be adjusted according to the types of nitrogen-containing compounds and peroxides, so that the nitrogen-containing compounds and peroxides can be dispersed in water.

According to the method of the present invention, it is also possible to optimize the types of nitrogen-containing compounds and peroxides according to the types of nitrogen-containing compounds and peroxides, so that the prepared heteroatom-containing nano-carbon materials can be used as hydrocarbon dehydrogenation reaction Catalyst can get better catalytic reaction effect.

In a preferred embodiment, the nitrogen-containing compound is NH ₃ , the peroxide is selected from hydrogen peroxide, and the weight ratio of raw material nano-carbon material: nitrogen-containing compound: peroxide is 1:0.02-5 :0.01-5, preferably 1:0.02-2.5:0.1-5, more preferably 1:0.1-2:0.4-4.5, still more preferably 1:0.2-0.5:0.5-1. In this preferred embodiment, the molar ratio of the nitrogen-containing compound to the peroxide is preferably 1:0.02-2, more preferably 1:0.1-1.8, even more preferably 1:1-1.5. In this preferred embodiment, the weight ratio of raw material nano-carbon material:H ₂ O is preferably 1:5-300, more preferably 1:10-250, even more preferably 1:20-50.

In another preferred embodiment, the nitrogen-containing compound is hydrazine, the peroxide is selected from tert-butyl hydroperoxide, and the raw material nano-carbon material: nitrogen-containing compound: the weight ratio of the peroxide is 1: 0.02-5:0.01-8, more preferably 1:0.08-3:0.02-5, still more preferably 1:0.1-0.5:0.1-1. In this preferred embodiment, the molar ratio of the nitrogen-containing compound to the peroxide is preferably 1:0.001-8, more preferably 1:0.003-6, even more preferably 1:0.1-0.5. In this preferred embodiment, the weight ratio of raw material nano-carbon material: H ₂ O is preferably 1:5-300, more preferably 1:10-200, further preferably 1:40-60.

In yet another preferred embodiment, the nitrogen-containing compound is urea, the peroxide is selected from cumene hydroperoxide, and the raw material nano-carbon material: nitrogen-containing compound: the weight ratio of the peroxide is 1: 0.02-5:0.01-3, preferably 1:0.05-2:0.05-2, more preferably 1:0.2-0.5:0.1-1. In this preferred embodiment, the molar ratio of nitrogen-containing compound to peroxide is preferably 1:0.005-4, more preferably 1:0.05-2. In this preferred embodiment, the weight ratio of raw material nano-carbon material:H ₂ O is preferably 1:5-300, more preferably 1:10-250, even more preferably 1:10-50.

According to the method of the present invention, the conditions of the reaction shall be sufficient to increase the content of oxygen atoms and nitrogen atoms in the raw nano-carbon material. Preferably, during the reaction, the temperature of the aqueous dispersion is in the range of 80-220°C. When the temperature of the aqueous dispersion is within the above range, not only can the content of oxygen atoms and nitrogen atoms in the raw nano-carbon material be effectively increased, but also the structure and morphology of the raw nano-carbon material will not be significantly affected. More preferably, during the reaction, the temperature of the aqueous dispersion is in the range of 100-180°C. The duration of the reaction can be selected according to the reaction temperature, subject to the fact that a sufficient amount of oxygen atoms and nitrogen atoms can be introduced into the raw nano-carbon material. Generally, the duration of the reaction may be in the range of 0.5-96 hours, preferably in the range of 2-72 hours, more preferably in the range of 20-50 hours.

According to the method of the present invention, various commonly used methods can be used to form the aqueous dispersion, for example, the raw material nano-carbon material can be dispersed in water (preferably deionized water), and then the nitrogen-containing compound and the peroxide to obtain the aqueous dispersion. The nitrogen-containing compound and the peroxide may be provided in the form of a solution or in the form of a pure substance depending on the specific substance, and are not particularly limited. In order to further improve the dispersion effect of the raw material nano-carbon material and shorten the dispersion time, the raw material nano-carbon material can be dispersed in water by means of ultrasonic oscillation. The conditions of the ultrasonic oscillation can be conventionally selected, generally, the frequency of the ultrasonic oscillation can be 10-100 kHz, and the duration of the ultrasonic oscillation can be 0.1-6 hours, preferably 0.5-2 hours.

According to the method of the present invention, the content of O element and N element in the raw nano-carbon material is not particularly limited, and can be conventionally selected. Generally, the content of O element in the raw nano-carbon material is not higher than 1.2% by weight, preferably not higher than 0.5% by weight; the content of N element is not higher than 0.5% by weight, preferably not higher than 0.2% by weight %, more preferably not higher than 0.1 wt%, even more preferably not higher than 0.05 wt%. According to the method of the present invention, the total amount (calculated as elements) of the remaining non-metallic heteroatoms (such as phosphorus atoms and sulfur atoms) except oxygen atoms and nitrogen atoms in the raw nano-carbon material can be a conventional content. Generally, the total amount of other non-metallic heteroatoms except oxygen atoms and nitrogen atoms in the raw nano-carbon material is not higher than 0.5% by weight, preferably not higher than 0.2% by weight, more preferably not higher than 0.1% by weight. % by weight, more preferably not higher than 0.05% by weight. According to the method of the present invention, the raw nano-carbon material may also contain some metal elements according to different sources, and these metal elements usually originate from the catalyst used when preparing the raw nano-carbon material, and its content is generally below 2% by weight, preferably It is at most 1% by weight, more preferably at most 0.5% by weight.

According to the method of the present invention, the raw nano-carbon material can be pretreated (such as washing) by methods commonly used in the art before use to remove some impurities on the surface of the raw nano-carbon material; it can also be used directly without pretreatment. In the disclosed embodiments of the invention, the raw material nano-carbon materials are not pretreated before use.

According to the method of the present invention, nano-carbon materials in various forms can be processed, thereby increasing the content of oxygen atoms and nitrogen atoms in the nano-carbon materials. The raw nano-carbon material may be, but not limited to, one or a combination of two or more of carbon nanotubes, graphene, nano-diamonds, thin-layer graphite, nano-carbon particles, nano-carbon fibers and fullerenes. The carbon nanotubes may be one or a combination of two or more of single-walled carbon nanotubes, double-walled carbon nanotubes and multi-walled carbon nanotubes. Preferably, the raw nanocarbon material is carbon nanotubes, more preferably multi-walled carbon nanotubes.

In a preferred embodiment, the raw carbon nanomaterial is multi-walled carbon nanotubes, and the specific surface area of the multi-walled carbon nanotubes is 20-500m ² /g, preferably 50-300m ² /g, more Preferably it is 80-250 m ² /g, more preferably 90-150 m ² /g. When the specific surface area of the multi-walled carbon nanotubes is within the above range, the resulting heteroatom-containing nanocarbon material has better catalytic activity, especially when used as a catalyst for the dehydrogenation reaction of hydrocarbons, A better catalytic effect can be obtained.

When the raw nano-carbon material is a multi-walled carbon nanotube, the weight loss rate of the multi-walled carbon nanotube in the temperature range of 400-800°C is w ₈₀₀ , and the weight loss rate in the temperature range of 400-500°C is is w ₅₀₀ , and w ₅₀₀ /w ₈₀₀ is preferably in the range of 0.01-0.5, more preferably in the range of 0.02-0.2. The heteroatom-containing nano-carbon material thus prepared shows better catalytic effect, especially when used as a catalyst for the dehydrogenation reaction of hydrocarbons, better catalytic effect can be obtained.

In a more preferred embodiment of the present invention, the raw material nano-carbon material is a multi-walled carbon nanotube, and the specific surface area of the multi-walled carbon nanotube is 20-500m ² /g, preferably 50-300m ² /g, more preferably 80-250m ² /g, further preferably 90-150m ² /g; the weight loss rate of the multi-walled carbon nanotubes in the temperature range of 400-800°C is w ₈₀₀ , at 400- The weight loss ratio w ₅₀₀ in the temperature range of 500°C, w ₅₀₀ /w ₈₀₀ is preferably in the range of 0.01-0.5, more preferably in the range of 0.02-0.2.

According to the method of the present invention, the reaction is carried out in a closed container. The reaction can be carried out under autogenous pressure (ie, without the application of additional pressure) or under pressurized conditions. Preferably, the reaction is performed under autogenous pressure. The airtight container can be a common reactor that can be sealed and heated, such as a high-pressure reactor.

According to the method of the present invention, it may also include separating solid matter from the mixture obtained from the reaction, and drying the separated solid matter, so as to obtain the heteroatom-containing nano-carbon material.

The solid substance can be separated from the mixture obtained by the reaction by a common solid-liquid separation method, such as one or a combination of two or more of centrifugation, filtration and decantation.

The drying conditions can be selected conventionally, subject to the ability to remove volatile substances in the separated solid substances. Generally, the drying can be carried out at a temperature of 50-200°C, preferably at a temperature of 80-180°C, more preferably at a temperature of 120-150°C. The duration of the drying can be selected according to the temperature and manner of drying. Generally, the duration of the drying may be 0.5-48 hours, preferably 3-24 hours, more preferably 5-12 hours. The drying may be performed under normal pressure (ie, 1 standard atmospheric pressure) or under reduced pressure. From the viewpoint of further improving drying efficiency, the drying is preferably performed under reduced pressure.

According to the method of the invention, the content of oxygen atoms and nitrogen atoms in the raw nano-carbon material can be effectively increased without significantly affecting the structure of the raw nano-carbon material.

Thus, according to a third aspect of the present invention, the present invention provides a heteroatom-containing nanocarbon material prepared by the method according to the present invention.

According to the fourth aspect of the present invention, the present invention provides a heteroatom-containing nano-carbon material, which is the heteroatom-containing nano-carbon material according to the first aspect of the present invention or the heteroatom-containing nano-carbon material according to the first aspect of the present invention. Three aspects of heteroatom-containing nano-carbon materials are prepared by firing.

The calcination can be performed under conventional conditions. Preferably, the calcination is performed at a temperature of 250-500°C. More preferably, the calcination is carried out at a temperature of 300-450°C. The duration of the calcination can be selected according to the temperature of calcination. Generally, the duration of the calcination may be 1-24 hours, preferably 2-12 hours. The calcination may be performed in an oxygen-containing atmosphere, or in an atmosphere formed of an inert gas. The oxygen-containing atmosphere may be an air atmosphere; it may also be a mixed atmosphere formed by mixing oxygen and an inert gas, and the content of oxygen in the mixed atmosphere may be 0.1-22% by volume. The inert gas may include but not limited to nitrogen and/or a rare gas, and the rare gas may be argon and/or helium. From the viewpoints of convenience and cost, preferably, the calcination is carried out in an oxygen-containing atmosphere (such as an air atmosphere).

The heteroatom-containing nano-carbon material according to the present invention or the heteroatom-containing nano-carbon material prepared by the method of the present invention has good catalytic performance, especially high catalytic activity in the dehydrogenation reaction of hydrocarbons.

The heteroatom-containing nano-carbon material according to the present invention or the heteroatom-containing nano-carbon material prepared by the method of the present invention can be used directly as a catalyst, or in the form of a shaped catalyst. The shaped catalyst may contain the heteroatom-containing nano-carbon material according to the present invention or the heteroatom-containing nano-carbon material prepared by the method of the present invention and a binder. The binder can be selected according to the specific use occasion of the shaped catalyst so as to meet the requirements of use, for example, it can be an organic binder and/or an inorganic binder. The organic binder may be various common polymer binders, and the inorganic binder may be various common heat-resistant inorganic oxides, such as aluminum oxide and/or silicon oxide. When the shaped catalyst is a shaped catalyst that has a catalytic effect on hydrocarbon dehydrogenation reactions (such as direct dehydrogenation reactions and oxidative dehydrogenation reactions), especially oxidative dehydrogenation reactions, the binder is preferably an inorganic binder . In the shaped catalyst, the content of the heteroatom-containing nano-carbon material can be selected according to specific use requirements, and is not particularly limited. Generally, based on the total amount of the shaped catalyst, the content of the heteroatom-containing nano-carbon material It can be 5-95% by weight.

According to the fifth aspect of the present invention, the present invention provides the heteroatom-containing nano-carbon material according to the first aspect of the present invention, the heteroatom-containing nano-carbon material according to the third aspect of the present invention, or the fourth aspect of the present invention Aspects of the application of heteroatom-containing carbon nanomaterials as catalysts for hydrocarbon dehydrogenation reactions.

According to the application of the present invention, the heteroatom-containing nano-carbon material can be directly used in the hydrocarbon dehydrogenation reaction, or can be used in the hydrocarbon dehydrogenation reaction after molding. The dehydrogenation reaction can be carried out in the presence of oxygen, or it can not be carried out in the presence of oxygen. Preferably, the dehydrogenation reaction is carried out in the presence of oxygen, so as to obtain better catalytic effect.

According to the sixth aspect of the present invention, the present invention provides a hydrocarbon dehydrogenation reaction method, the method comprising the presence or absence of oxygen, under the hydrocarbon dehydrogenation reaction conditions, the hydrocarbon and the first The heteroatom-containing nano-carbon material according to the first aspect, the heteroatom-containing nano-carbon material according to the third aspect of the present invention, or the heteroatom-containing nano-carbon material according to the fourth aspect of the present invention.

According to the hydrocarbon dehydrogenation reaction method of the present invention, the heteroatom-containing nano-carbon material can be directly used for contacting hydrocarbons, or the heteroatom-containing nano-carbon material can be used for contacting hydrocarbons after molding.

According to the hydrocarbon dehydrogenation reaction method of the present invention, various types of hydrocarbons can be dehydrogenated to obtain unsaturated hydrocarbons, such as olefins. The process according to the invention is particularly suitable for the dehydrogenation of alkanes to give alkenes. According to the method of the present invention, the hydrocarbon is preferably an alkane, such as a C ₂ -C ₁₂ alkane. Specifically, the hydrocarbon may be, but not limited to, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane, cyclopentane, n-hexane, 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane, cyclohexane, methylcyclopentane, n-heptane, 2-methylhexane, 3-methylhexane, 2-ethylpentane alkanes, 3-ethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, n-octane, 2-methylheptane, 3-methylheptane, 4-methylpentane Heptane, 2,3-Dimethylhexane, 2,4-Dimethylhexane, 2,5-Dimethylhexane, 3-Ethylhexane, 2,2,3-Trimethyl Pentane, 2,3,3-trimethylpentane, 2,4,4-trimethylpentane, 2-methyl-3-ethylpentane, n-nonane, 2-methyloctane, 3-methyloctane, 4-methyloctane, 2,3-dimethylheptane, 2,4-dimethylheptane, 3-ethylheptane, 4-ethylheptane, 2, 3,4-trimethylhexane, 2,3,5-trimethylhexane, 2,4,5-trimethylhexane, 2,2,3-trimethylhexane, 2,2, 4-trimethylhexane, 2,2,5-trimethylhexane, 2,3,3-trimethylhexane, 2,4,4-trimethylhexane, 2-methyl-3 -Ethylhexane, 2-methyl-4-ethylhexane, 3-methyl-3-ethylhexane, 3-methyl-4-ethylhexane, 3,3-diethylpentane alkanes, 1-methyl-2-ethylcyclohexane, 1-methyl-3-ethylcyclohexane, 1-methyl-4-ethylcyclohexane, n-propylcyclohexane, isopropyl Cyclohexane, trimethylcyclohexane (including various isomers of trimethylcyclohexane, such as 1,2,3-trimethylcyclohexane, 1,2,4-trimethylcyclohexane Hexane, 1,2,5-trimethylcyclohexane, 1,3,5-trimethylcyclohexane), n-decane, 2-methylnonane, 3-methylnonane, 4- Methylnonane, 5-methylnonane, 2,3-dimethyloctane, 2,4-dimethyloctane, 3-ethyloctane, 4-ethyloctane, 2,3, 4-Trimethylheptane, 2,3,5-Trimethylheptane, 2,3,6-Trimethylheptane, 2,4,5-Trimethylheptane, 2,4,6- Trimethylheptane, 2,2,3-trimethylheptane, 2,2,4-trimethylheptane, 2,2,5-trimethylheptane, 2,2,6-trimethylheptane Heptane, 2,3,3-trimethylheptane, 2,4,4-trimethylheptane, 2-methyl-3-ethylheptane, 2-methyl-4-ethylheptane Alkanes, 2-methyl-5-ethylheptane, 3-methyl-3-ethylheptane, 4-methyl-3-ethylheptane, 5-methyl-3-ethylheptane, 4-methyl-4-ethylheptane, 4-propylheptane, 3,3-diethylhexane, 3,4-diethylhexane, 2-methyl-3,3-diethyl Phenylpentane, phenylethane, 1-phenylpropane, 2-phenylpropane, 1-phenylbutane, 2-phenylbutane, 1-phenylpentane, 2-phenylpentane and 3- One or more combinations of phenylpentanes.

More preferably, the hydrocarbon is one or more than two of propane, n-butane, isobutane and ethyl phenylene. Further preferably, the hydrocarbon is n-butane.

According to the hydrocarbon dehydrogenation reaction method of the present invention, the reaction can be carried out in the presence of oxygen or in the absence of oxygen. Preferably, the hydrocarbon dehydrogenation reaction method according to the present invention is carried out in the presence of oxygen. When the method of the present invention is carried out in the presence of oxygen, the amount of oxygen used can be conventionally selected. Generally, the molar ratio of hydrocarbon to oxygen may be 0.01-100:1, preferably 0.1-10:1, more preferably 0.2-5:1, most preferably 0.3-2:1.

According to the hydrocarbon dehydrogenation reaction method of the present invention, the hydrocarbon and optional oxygen can be sent into the reactor through the carrier gas to contact and react with the heteroatom-containing nano-carbon material. The carrier gas can be a commonly used gas that will not chemically interact with the reactants and reaction products and will not decompose under the reaction conditions, such as one or both of nitrogen, carbon dioxide, rare gases and water vapor combination of the above. The amount of the carrier gas can be conventionally selected. Generally, the content of the carrier gas can be 30-99.5% by volume, preferably 50-99% by volume, more preferably 70-98% by volume.

According to the hydrocarbon dehydrogenation reaction method of the present invention, the contact temperature can be conventionally selected, whichever is sufficient to cause the hydrocarbon dehydrogenation reaction to occur. Generally, the contacting can be carried out at a temperature of 200-650°C, preferably at a temperature of 300-600°C, more preferably at a temperature of 350-550°C, further preferably at a temperature of 400-450°C conduct.

According to the hydrocarbon dehydrogenation reaction method of the present invention, the contacting may be performed in a fixed bed reactor or a fluidized bed reactor, and is not particularly limited. Preferably, the contacting is performed in a fixed bed reactor.

According to the hydrocarbon dehydrogenation reaction method of the present invention, the duration of the contact can be selected according to the temperature of the contact, such as when the contact is carried out in a fixed bed reactor, the gas hourly volume space velocity of the feed can be used to represent the contact duration. Generally, the gas hourly volume space velocity of the feed can be 0.1-10000h ^-1 , preferably 1-6000h ^-1 , more preferably 5-5000h ^-1 , further preferably 10-4000h ^{-1 ,} such as 600-1200h -1 ¹ .

The present invention will be described in detail below in conjunction with the examples, but the scope of the present invention is not limited thereby.

In the following examples and comparative examples, the X-ray photoelectron spectroscopy analysis is tested on the ESCALab250 type X-ray photoelectron spectroscopy instrument equipped with ThermoAvantageV5.926 software of ThermoScientific Company, and the excitation source is monochromatic AlKα X-ray, and the energy is 1486.6eV , the power is 150W, the penetration energy used for the narrow scan is 30eV, the basic vacuum during the analysis and test is 6.5×10 ^-10 mbar, the electron binding energy is corrected by the C1s peak (284.0eV) of elemental carbon, and the data processing is performed on the ThermoAvantage software , in the analysis module, the sensitivity factor method is used for quantitative analysis. The samples were dried in a helium atmosphere at a temperature of 150° C. and a pressure of 1 standard atmosphere for 3 hours before testing.

In the following examples and comparative examples, thermogravimetric analysis was carried out on a TA5000 thermal analyzer, the test condition was air atmosphere, the heating rate was 10°C/min, and the temperature range was from room temperature (25°C) to 1000°C. The samples were dried in a helium atmosphere at a temperature of 150° C. and a pressure of 1 standard atmosphere for 3 hours before testing. The specific surface area was measured using an ASAP2000 _N2 physical adsorption instrument from Micromertrics, USA. The microscopic morphology of the raw nano-carbon materials and heteroatom-containing nano-carbon materials was analyzed by high-resolution transmission electron microscope produced by FEI Company of the United States.

Examples 1-38 are used to illustrate the heteroatom-containing nano-carbon material and its preparation method of the present invention.

Example 1

(1) 20g of multi-walled carbon nanotubes (specific surface area is 136m ² /g, oxygen atom content is 0.3% by weight, nitrogen atom content is 0.02% by weight) as raw material nano-carbon material, and the rest except nitrogen atom and oxygen atom The total content of non-metallic heteroatoms (phosphorus atoms and sulfur atoms) is 0.01% by weight, the total content of metal atoms is 0.1% by weight, and the weight loss rate is w ₈₀₀ in the temperature range of 400-800°C, and in the temperature range of 400-500°C The weight loss ratio within is w ₅₀₀ , w ₅₀₀ /w ₈₀₀ is 0.12, purchased from Chengdu Organic Chemistry Co., Ltd., Chinese Academy of Sciences) and dispersed in deionized water, wherein, the dispersion is carried out under ultrasonic oscillation conditions, and the ultrasonic oscillation conditions include: the frequency is 14kHz , the time is 0.5 hours. Then, add _NH3 and hydrogen peroxide to the aqueous dispersion, and stir evenly, thereby obtaining the aqueous dispersion, wherein, _NH3 and hydrogen peroxide are respectively provided in the form of 25% by weight aqueous solution, according to the raw material nano-carbon material: _NH3 : The weight ratio of hydrogen peroxide: H ₂ O is 1:0.5:1:20.

(2) The obtained aqueous dispersion was reacted for 24 hours under autogenous pressure at a temperature of 130° C. in a polytetrafluoroethylene-lined autoclave. After the reaction, after the temperature in the autoclave dropped to room temperature, the autoclave was opened, the reaction mixture was filtered and washed, and the solid matter was collected. After drying the collected solid matter at normal pressure (1 standard atmospheric pressure, the same below) and a temperature of 120°C for 12 hours, a heteroatom-containing nano-carbon material is obtained. The composition, specific surface area and w of the heteroatom-containing nano-carbon material ₅₀₀ /w ₈₀₀ are listed in Table 1.

Fig. 1 is a transmission electron micrograph of the prepared heteroatom-containing nano-carbon material, and Fig. 2 is a transmission electron micrograph of multi-walled carbon nanotubes as a raw material. From Figure 1 and Figure 2, it can be seen that the microscopic morphology of heteroatom-containing carbon nanomaterials is good, indicating that the reaction process has little effect on the structure of nanocarbon materials.

Comparative example 1

The same aqueous dispersion as in Example 1 was placed in a three-necked flask equipped with a condenser, and the three-necked flask was placed in an oil bath at 130° C., and refluxed under normal pressure for 24 hours. After the reaction, after the temperature in the three-neck flask dropped to room temperature, the reaction mixture was filtered and washed, and the solid matter was collected. The collected solid matter was dried under normal pressure at a temperature of 120° C. for 6 hours to obtain a heteroatom-containing nano-carbon material. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Comparative example 2

Adopt the same method as Example 1 to prepare the heteroatom-containing nano-carbon material, the difference is that the aqueous dispersion prepared in step (1) does not contain hydrogen peroxide, that is, the multi-walled carbon nanotube as the raw material nano-carbon material Disperse in deionized water, then add NH ₃ and stir evenly to obtain an aqueous dispersion, wherein the weight ratio of the raw material nano-carbon material: NH ₃ : hydrogen peroxide: H ₂ O is 1:0.5:0:20 Ratio feeding. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Comparative example 3

Adopt the same method as Example 1 to prepare heteroatom-containing nano-carbon materials, the difference is that the aqueous dispersion prepared in step (1) does not contain NH ₃ , that is, the multi-walled carbon nanotubes as raw material nano-carbon materials are dispersed In deionized water, then add hydrogen peroxide and stir evenly to obtain a water dispersion, wherein, according to the weight ratio of raw material nano-carbon material: NH ₃ : hydrogen peroxide: H ₂ O is 1:0:1:20 Ratio feeding. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Comparative example 4

The heteroatom-containing nano-carbon material prepared by the same method as Comparative Example 2 was dispersed in deionized water, and the dispersion was carried out under ultrasonic oscillation conditions. The ultrasonic oscillation conditions included: the frequency was 110 kHz, and the time was 1 hour. Then, add hydrogen peroxide and stir evenly to obtain an aqueous dispersion, wherein the weight ratio of raw material nano-carbon material:hydrogen peroxide:H ₂ O is 1:0.5:20.

The obtained aqueous dispersion was placed in a polytetrafluoroethylene-lined autoclave, and reacted at a temperature of 130° C. under autogenous pressure for 24 hours. After the reaction, after the temperature in the autoclave dropped to room temperature, the autoclave was opened, the reaction mixture was filtered and washed, and the solid matter was collected. After drying the collected solid matter at normal pressure and a temperature of 120° C. for 12 hours, a heteroatom-containing nanocarbon material was obtained. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the heteroatom-containing nanocarbon material are listed in Table 1 listed.

Comparative example 5

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 1, except that in step (1), hydrogen peroxide was replaced by an equimolar amount of H ₂ SO ₄ . The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Comparative example 6

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 1, except that in step (1), hydrogen peroxide was replaced by an equimolar amount of KMnO ₄ . The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Comparative example 7

Adopt the same method as Example 1 to prepare the heteroatom-containing nano-carbon material, the difference is that hydrogen peroxide is not used in step (1); After the ozone, close the autoclave to react. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 2

The same method as in Example 1 is used to prepare heteroatom-containing nano-carbon materials. The difference is that in step (1), the ratio of multi-walled carbon nanotubes (purchased from Shandong Dazhan Nano Materials Co., Ltd.) as raw material nano-carbon materials The surface area is 251m ² /g, the weight loss rate is w ₈₀₀ in the temperature range of 400-800°C, the weight loss rate is w ₅₀₀ in the temperature range of 400-500°C, the w ₅₀₀ /w ₈₀₀ is 0.33, and the oxygen atom content 0.62% by weight, nitrogen atom content is 0.01% by weight, the total content of other non-metallic heteroatoms (phosphorus and sulfur atoms) except nitrogen atom and oxygen atom is 0.01% by weight, and the total content of metal atoms is 0.08% by weight. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 3

Adopt the same method as Example 1 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (2), the obtained aqueous dispersion is placed in a high-pressure reactor with a polytetrafluoroethylene liner at 80 ° C Under the temperature of , react under autogenous pressure for 24 hours. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 4

Using the same method as in Example 1 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (1), the raw material nano-carbon materials: NH ₃ : hydrogen peroxide: H ₂ O weight ratio is 1:0.02: Feeding ratio of 0.04:10. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 5

(1) 20g of multi-walled carbon nanotubes (specific surface area is 103m ² /g, oxygen atom content is 0.2% by weight, nitrogen atom content is 0.01% by weight) as raw material nano carbon material, and all the others except nitrogen atom and oxygen atom The total content of non-metallic heteroatoms (phosphorus atoms and sulfur atoms) is 0.04% by weight, the total content of metal atoms is 0.3% by weight, and the weight loss rate is w ₈₀₀ in the temperature range of 400-800°C. The weight loss rate in the temperature interval is w ₅₀₀ , w ₅₀₀ /w ₈₀₀ is 0.07, purchased from Chengdu Organic Chemistry Co., Ltd., Chinese Academy of Sciences) dispersed in deionized water, and dispersed under ultrasonic oscillation conditions, the ultrasonic oscillation conditions include: the frequency is 90kHz , the time is 2 hours, then add NH ₃ and hydrogen peroxide, and stir evenly to obtain a water dispersion, wherein, NH ₃ and hydrogen peroxide are provided in the form of 20% by weight aqueous solution respectively, according to the raw material nano-carbon material: NH ₃ : The weight ratio of hydrogen peroxide: H ₂ O is 1:0.2:0.5:50.

(2) The obtained aqueous dispersion was reacted for 36 hours under autogenous pressure at a temperature of 160° C. in a polytetrafluoroethylene-lined autoclave. After the reaction, after the temperature in the autoclave dropped to room temperature, the autoclave was opened, the reaction mixture was filtered and washed, and the solid matter was collected. After drying the collected solid matter at normal pressure and a temperature of 140° C. for 8 hours, a heteroatom-containing nanocarbon material was obtained. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the heteroatom-containing nanocarbon material are listed in Table 1 listed.

Example 6

The same method as in Example 5 is used to prepare heteroatom-containing nano-carbon materials. The difference is that in step (1), the ratio of multi-walled carbon nanotubes (purchased from Shandong Dazhan Nano Materials Co., Ltd.) Surface area is 103m ² /g, w ₅₀₀ /w ₈₀₀ is 0.23, oxygen atom content is 1.1% by weight, nitrogen atom content is 0.03% by weight, all the other non-metallic heteroatoms (phosphorus atom and sulfur atom) except nitrogen atom and oxygen atom ) is 0.01% by weight, and the total content of metal atoms is 1.6% by weight. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 7

Using the same method as in Example 5 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (2), the obtained aqueous dispersion is placed in a high-pressure reactor with a polytetrafluoroethylene liner at 200 ° C. Under the temperature of , react under autogenous pressure for 36 hours. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 8

Using the same method as in Example 5 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (1), the raw material nano-carbon materials: NH ₃ : hydrogen peroxide: H ₂ O weight ratio is 1:2: Feeding ratio of 0.1:250. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 9

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 5, except that in step (1), the hydrogen peroxide was replaced by an equimolar amount of tert-butyl hydroperoxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 10

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 5, except that in step (1), hydrogen peroxide was replaced by an equimolar amount of dicumyl peroxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Comparative example 8

Adopt the same method as in Example 10 to prepare heteroatom-containing nano-carbon materials, the difference is that the aqueous dispersion prepared in step (1) does not contain NH ₃ , that is, the multi-walled carbon nanotubes used as raw material nano-carbon materials are dispersed In deionized water, then add dicumyl peroxide and stir evenly to obtain an aqueous dispersion, wherein, according to the raw material nano-carbon material: NH ₃ : dicumyl peroxide: H ₂ O weight ratio is 1: 0:0.7:50 ratio feeding. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 1.

Example 11

Adopt the method identical with embodiment 1 to prepare containing heteroatom nano-carbon material, difference is as follows:

In step (1), disperse the raw nano-carbon material in deionized water, then add hydrazine and hydrogen peroxide, and stir evenly to obtain an aqueous dispersion, wherein the hydrazine and hydrogen peroxide are in the form of a 25% by weight aqueous solution Provided, according to the weight ratio of raw material nano-carbon material: hydrazine: hydrogen peroxide: H ₂ O is 1:0.1:0.5:25;

In step (2), the obtained aqueous dispersion was placed in a high-pressure reactor with a polytetrafluoroethylene liner, and reacted at a temperature of 150° C. for 24 hours under autogenous pressure.

The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Comparative example 9

The same aqueous dispersion as in Example 11 was placed in a three-necked flask equipped with a condenser, and the three-necked flask was placed in an oil bath at 150° C., and refluxed under normal pressure for 24 hours. After the reaction, after the temperature in the three-neck flask dropped to room temperature, the reaction mixture was filtered and washed, and the solid matter was collected. The collected solid matter was dried under normal pressure at a temperature of 120° C. for 6 hours to obtain a heteroatom-containing nano-carbon material. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Comparative example 10

The same method as in Example 11 is used to prepare heteroatom-containing nano-carbon materials. The difference is that the aqueous dispersion prepared in step (1) does not contain hydrazine, that is, the multi-walled carbon nanotubes used as raw material nano-carbon materials are dispersed in Add hydrogen peroxide to deionized water and stir evenly to obtain an aqueous dispersion, wherein the weight ratio of raw material nano-carbon material: hydrazine: hydrogen peroxide: H ₂ O is 1:0:0.6:25 . The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Comparative example 11

The same method as in Example 11 is used to prepare heteroatom-containing nano-carbon materials. The difference is that the aqueous dispersion prepared in step (1) does not contain hydrogen peroxide, that is, the multi-walled carbon nanotubes used as raw material nano-carbon materials Disperse in deionized water, then add hydrazine, and stir evenly to obtain an aqueous dispersion, wherein the raw material nano-carbon material: hydrazine: hydrogen peroxide: H ₂ O is fed in a ratio of 1:0.6:0:25 by weight . The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 12

The same method as in Example 11 was used to prepare heteroatom-containing nano-carbon materials, except that in step (2), the obtained aqueous dispersion was placed in a high-pressure reactor with a polytetrafluoroethylene liner at 190 ° C. Under the temperature of , react under autogenous pressure for 24 hours. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 13

The same method as in Example 11 was used to prepare heteroatom-containing carbon nanomaterials, except that in step (1), the multi-walled carbon nanotubes used as raw material nanocarbon materials were the same as in Example 2. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 14

Using the same method as in Example 11 to prepare heteroatom-containing carbon nanomaterials, the difference is that in step (1), the weight ratio of raw material nanocarbon materials: hydrazine: hydrogen peroxide: H ₂ O is 1:2:5 : Feeding ratio of 200. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 15

Adopt the method identical with embodiment 5 to prepare containing heteroatom nano-carbon material, difference is as follows:

In step (1), disperse the raw nano-carbon material in deionized water, then add hydrazine and tert-butyl hydroperoxide, and stir evenly to obtain an aqueous dispersion, wherein hydrazine is provided in the form of an 85% by weight aqueous solution, According to the raw material nano-carbon material: hydrazine: tert-butyl hydroperoxide: _H2O , the weight ratio is 1:0.5:0.5:50;

In step (2), the obtained aqueous dispersion was reacted for 48 hours under autogenous pressure at a temperature of 120° C. in a high-pressure reactor with a polytetrafluoroethylene liner.

The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 16

The same method as in Example 15 was used to prepare heteroatom-containing carbon nanomaterials, except that in step (1), the multi-walled carbon nanotubes used as raw material nanocarbon materials were the same as in Example 6. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 17

Using the same method as in Example 15 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (1), the weight ratio of raw material nano-carbon materials: hydrazine: tert-butyl hydroperoxide: H ₂ O is 1: 2:0.02:10 ratio feeding. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 18

Adopt the same method as in Example 15 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (2), the obtained aqueous dispersion is placed in a high-pressure reactor with a polytetrafluoroethylene liner at 90 ° C Under the temperature of , react under autogenous pressure for 48 hours. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 19

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 15, except that in step (1), tert-butyl hydroperoxide was replaced by an equimolar amount of cyclohexyl hydroperoxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 20

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 15, except that in step (1), tert-butyl hydroperoxide was replaced by an equimolar amount of dicumyl peroxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 21

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 15, except that in step (1), tert-butyl hydroperoxide was replaced by an equimolar amount of hydrogen peroxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 22

Adopt the method identical with embodiment 1 to prepare containing heteroatom nano-carbon material, difference is as follows:

In step (1), disperse the raw material nano-carbon material in deionized water, then add urea and cumene hydroperoxide, and stir evenly to obtain a water dispersion, wherein, according to the raw material nano-carbon material: urea: hydrogen peroxide The weight ratio of cumene: H ₂ O is 1:0.5:0.1:15;

In step (2), the obtained aqueous dispersion was placed in a high-pressure reactor with a polytetrafluoroethylene liner, and reacted at a temperature of 150° C. for 24 hours under autogenous pressure.

The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Comparative example 12

The same aqueous dispersion as in Example 22 was placed in a three-necked flask equipped with a condenser, and the three-necked flask was placed in an oil bath at 150° C., and refluxed under normal pressure for 24 hours. After the reaction, after the temperature in the three-neck flask dropped to room temperature, the reaction mixture was filtered and washed, and the solid matter was collected. The collected solid matter was dried under normal pressure at a temperature of 120° C. for 6 hours to obtain a heteroatom-containing nano-carbon material. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Comparative example 13

The same method as in Example 22 is used to prepare heteroatom-containing nano-carbon materials. The difference is that the aqueous dispersion prepared in step (1) does not contain urea, that is, the multi-walled carbon nanotubes used as raw material nano-carbon materials are dispersed in In deionized water, then add cumene hydroperoxide and stir evenly to obtain an aqueous dispersion, wherein, according to the raw material nano-carbon material: urea: cumene hydroperoxide: H ₂ O, the weight ratio is 1:0: Feeding ratio of 0.6:15. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Comparative example 14

The same method as in Example 22 is used to prepare heteroatom-containing nano-carbon materials. The difference is that the aqueous dispersion prepared in step (1) does not contain cumene hydroperoxide, that is, the multi-walled nano-carbon materials used as raw materials Carbon nanotubes are dispersed in deionized water, then urea is added, and stirred evenly to obtain an aqueous dispersion, wherein, according to the raw material nanocarbon material: urea: cumene hydroperoxide: H ₂ O, the weight ratio is 1:0.6: 0:15 ratio feeding. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 23

The same method as in Example 22 was used to prepare heteroatom-containing nano-carbon materials, except that in step (2), the obtained aqueous dispersion was placed in a high-pressure reactor with a polytetrafluoroethylene liner at 220 ° C. Under the temperature of , react under autogenous pressure for 24 hours. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 24

The same method as in Example 22 was used to prepare heteroatom-containing carbon nanomaterials, except that the multi-walled carbon nanotubes used as raw material nanocarbon materials were the same as in Example 2. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 25

Using the same method as in Example 22 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (1), the weight ratio of raw material nano-carbon materials: urea: cumene hydroperoxide: H ₂ O is 1: Feeding ratio of 0.05:0.1:250. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 26

Adopt the method identical with embodiment 5 to prepare containing heteroatom nano-carbon material, difference is as follows:

In step (1), disperse the raw material nano-carbon material in deionized water, then add urea and cumene hydroperoxide, and stir evenly to obtain a water dispersion, wherein, according to the raw material nano-carbon material: urea: hydrogen peroxide The weight ratio of cumene: H ₂ O is 1:0.2:1:40;

In step (2), the obtained aqueous dispersion was placed in a high-pressure reactor with a polytetrafluoroethylene liner, and reacted at a temperature of 120° C. for 48 hours under autogenous pressure.

The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 27

The same method as in Example 26 was used to prepare heteroatom-containing carbon nanomaterials, except that in step (1), the multi-walled carbon nanotubes used as raw material nanocarbon materials were the same as in Example 6. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 28

Using the same method as in Example 26 to prepare heteroatom-containing nano-carbon materials, the difference is that in step (1), the weight ratio of raw material nano-carbon materials: urea: cumene hydroperoxide: H ₂ O is 1: 2:0.05:100 ratio feeding. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 29

The same method as in Example 26 was used to prepare heteroatom-containing nano-carbon materials, except that in step (2), the obtained aqueous dispersion was placed in a high-pressure reactor with a polytetrafluoroethylene liner at 90 ° C. Under the temperature of , react under autogenous pressure for 48 hours. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 30

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 26, except that in step (1), cumene hydroperoxide was replaced by an equimolar amount of cyclohexyl hydroperoxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 31

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 26, except that in step (1), cumene hydroperoxide was replaced by dibenzoyl peroxide in an equimolar amount. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 32

The heteroatom-containing nano-carbon material was prepared by the same method as in Example 26, except that in step (1), cumene hydroperoxide was replaced by an equimolar amount of hydrogen peroxide. The composition, specific surface area and w ₅₀₀ /w ₈₀₀ of the prepared heteroatom-containing nanocarbon materials are listed in Table 2.

Example 33

The heteroatom-containing nanocarbon material prepared in Example 1 was calcined at 350° C. in an air atmosphere for 4 hours.

Comparative example 15

The heteroatom-containing nanocarbon material prepared in Comparative Example 1 was calcined at 350° C. in an air atmosphere for 4 hours.

Comparative example 16

The heteroatom-containing nanocarbon material prepared in Comparative Example 2 was calcined at 350° C. in an air atmosphere for 4 hours.

Comparative example 17-21

Comparative Example 17 The heteroatom-containing nano-carbon material prepared in Comparative Example 3 was calcined at 350° C. in an air atmosphere for 4 hours;

Comparative Example 18 The heteroatom-containing nano-carbon material prepared in Comparative Example 4 was calcined at 350° C. in an air atmosphere for 4 hours;

Comparative Example 19 The heteroatom-containing nano-carbon material prepared in Comparative Example 5 was calcined at 350° C. in an air atmosphere for 4 hours;

Comparative Example 20 The heteroatom-containing nano-carbon material prepared in Comparative Example 6 was calcined at 350° C. in an air atmosphere for 4 hours;

Comparative Example 21 The heteroatom-containing nanocarbon material prepared in Comparative Example 7 was calcined at 350° C. in an air atmosphere for 4 hours.

Example 34

The heteroatom-containing nano-carbon material prepared in Example 2 was calcined at 350° C. in an air atmosphere for 4 hours.

Example 35

The heteroatom-containing nanocarbon material prepared in Example 3 was calcined at 350° C. in an air atmosphere for 4 hours.

Example 36

The heteroatom-containing nanocarbon material prepared in Example 4 was calcined at 350° C. in an air atmosphere for 4 hours.

Example 37

The heteroatom-containing nano-carbon material prepared in Example 11 was calcined at 450° C. in an air atmosphere for 2 hours.

Example 38

The heteroatom-containing nanocarbon material prepared in Example 26 was calcined at 300° C. in an air atmosphere for 12 hours.

Examples 39-76 are used to illustrate the application of the heteroatom-containing nano-carbon material and the hydrocarbon dehydrogenation reaction method according to the present invention.

Examples 39-70

0.4g (packing volume: 3.7mL) of the heteroatom-containing nano-carbon materials prepared in Examples 1-32 were loaded as catalysts in a general-purpose fixed-bed micro-quartz tube reactor, and the two ends of the micro-quartz tube reactor were sealed with quartz sand. , under the conditions of 0.15MPa and 450°C, the gas containing hydrocarbons and oxygen (the concentration of n-butane is 2.0% by volume, the molar ratio of n-butane and oxygen is 1:3, and the balance is nitrogen as a carrier gas) in total The volumetric space velocity is 900h ^-1 is passed in the reactor to react, continuously monitors the composition of the reaction mixture output from the reactor, and calculates n-butane conversion rate, total olefin selectivity and total butene (for 1-butene and 2-butene) selectivity, the results of the reaction for 3 hours and 24 hours are listed in Table 3.

Comparative example 22-35

The reaction was carried out in the same manner as in Examples 39-70, except that the heteroatom-containing nano-carbon materials prepared in Comparative Examples 1-14 were used as catalysts. The reaction results are listed in Table 3.

Comparative example 36

The reaction was carried out in the same manner as in Examples 39-70, except that the same raw material nano-carbon material as in Example 1 was used as a catalyst. The reaction results are listed in Table 3.

Comparative example 37

The reaction was carried out in the same manner as in Examples 39-70, except that the same raw material nano-carbon material as in Example 5 was used as a catalyst. The reaction results are listed in Table 3.

Examples 71-76

The reaction was carried out in the same manner as in Examples 39-70, except that the heteroatom-containing carbon nanotubes prepared in Examples 33-38 were used as catalysts. The reaction results are listed in Table 4.

Comparative example 38-44

The reaction was carried out in the same manner as in Examples 39-70, except that the heteroatom-containing carbon nanotubes prepared in Comparative Examples 15-21 were used as catalysts. The reaction results are listed in Table 4.

Comparative example 45

The reaction was carried out in the same manner as in Examples 39-70, except that the catalyst was obtained by calcining the same raw nano-carbon material as in Example 1 in an air atmosphere at a temperature of 350° C. for 4 hours. The reaction results are listed in Table 4.

Comparative example 46

The reaction was carried out in the same manner as in Examples 39-70, except that the catalyst was obtained by calcining the same raw nano-carbon material as in Example 5 in an air atmosphere at a temperature of 300° C. for 12 hours. The reaction results are listed in Table 4.

table 3

Table 4

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention. These simple modifications All belong to the protection scope of the present invention.

In addition, it should be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way if there is no contradiction. The combination method will not be described separately.

In addition, various combinations of different embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the idea of the present invention, they should also be regarded as the disclosed content of the present invention.

Claims (30)

1. a nano-carbon material Han hetero atom, this contains hetero atom nano-carbon material and contains C element, O element and N element, on the basis of this total amount containing hetero atom nano-carbon material and in terms of element, the content of O element is 4-12 weight %, the content of N element is 2-6 weight %, and the content of C element is 82-94 weight %；

This contains in hetero atom nano-carbon material, the peak in the range of 531.0-532.5eV in x-ray photoelectron power spectrum the amount of the O element determined is I_O ^c, the peak in the range of 532.6-533.5eV in x-ray photoelectron power spectrum the amount of the O element determined is I_O ^e, I_O ^c/I_O ^eIn the range of 0.5-1；

This contains in hetero atom nano-carbon material, x-ray photoelectron power spectrum determine that this total amount containing the N element in hetero atom nano-carbon material is I_N ^t, the peak in the range of 398.5-400.1eV in x-ray photoelectron power spectrum the amount of the N element determined is I_N ^c, I_N ^c/I_N ^tIn the range of 0.8-1.

The most according to claim 1 containing hetero atom nano-carbon material, wherein, I_O ^c/I_O ^eIn the range of 0.5-0.95, preferably in the range of 0.6-0.8；I_N ^c/I_N ^tIn the range of 0.8-0.95.

The most according to claim 1 and 2 containing hetero atom nano-carbon material, wherein, this contains in hetero atom nano-carbon material, the peak in the range of 288.6-288.8eV in x-ray photoelectron power spectrum the amount of the C element determined is I_C ^c, the peak in the range of 286.0-286.2eV in x-ray photoelectron power spectrum the amount of the C element determined is I_C ^e, I_C ^c/I_C ^eIn the range of 0.3-1, preferably in the range of 0.4-0.95, more preferably in the range of 0.5-0.8.

4. according to described in any one in claim 1-3 containing hetero atom nano-carbon material, wherein, on the basis of the total amount of the C element determined by x-ray photoelectron power spectrum in this is containing hetero atom nano-carbon material, the content of the C element determined by the peak in the range of 284.7-284.9eV in x-ray photoelectron power spectrum is 70-92 weight %, it is preferably 75-85 weight %, the content of the C element determined by the peak in the range of 286.0-288.8eV in x-ray photoelectron power spectrum is 8-30 weight %, preferably 15-25 weight %.

5. according to described in any one in claim 1-4 containing hetero atom nano-carbon material, wherein, x-ray photoelectron power spectrum determine that this total amount containing the N element in hetero atom nano-carbon material is I_N ^t, the peak in the range of 400.6-401.5eV in x-ray photoelectron power spectrum the amount of the N element determined is I_N ^g, I_N ^g/I_N ^tFor not higher than 0.2, preferably in the range of 0-0.2, more preferably in the range of 0.05-0.2.

6. according to described in any one in claim 1-5 containing hetero atom nano-carbon material, wherein, on the basis of this total amount containing hetero atom nano-carbon material and in terms of element, the content of O element is 4-10 weight %, it is preferably 5-9 weight %, more preferably 5.5-8 weight %；The content of C element is 84.2-93.8 weight %, preferably 86-92.5 weight %, more preferably 87.5-91.5 weight %；The content of N element is 2.2-5.8 weight %, preferably 2.5-5 weight %, more preferably 3-4.5 weight %.

7. according to described in any one in claim 1-6 containing hetero atom nano-carbon material, wherein, this contains hetero atom nano-carbon material for containing hetero atom CNT；Preferably, this contains hetero atom nano-carbon material for containing hetero atom multi-walled carbon nano-tubes.

The most according to claim 7 containing hetero atom nano-carbon material, wherein, the described specific surface area containing hetero atom multi-walled carbon nano-tubes is 50-500m²/ g, preferably 80-300m²/ g, more preferably 90-200m²/ g, more preferably 100-150m²/g。

9. according to described in claim 7 or 8 containing hetero atom nano-carbon material, wherein, the described multi-walled carbon nano-tubes containing hetero atom weight-loss ratio in the temperature range of 400-800 DEG C is w₈₀₀, the weight-loss ratio in the temperature range of 400-500 DEG C is w₅₀₀, w₅₀₀/w₈₀₀In the range of 0.01-0.5, preferably in the range of 0.02-0.2, described weight-loss ratio measures in air atmosphere.

10. the preparation method containing hetero atom nano-carbon material, the method includes reacting a kind of aqueous dispersions being dispersed with raw material nano material with carbon element, at least one nitrogen-containing compound and at least one peroxide in hermetic container, and described nitrogen-containing compound is selected from NH₃, hydrazine and carbamide, in course of reaction, the temperature of described aqueous dispersions is maintained in the range of 80-220 DEG C.

11. methods according to claim 10, wherein, raw material nano material with carbon element: nitrogen-containing compound: the weight ratio of peroxide is 1:0.01-10:0.01-10, preferably 1:0.05-3:0.02-5, more preferably 1:0.1-0.5:0.1-1；

Raw material nano material with carbon element: H₂The weight ratio of O is 1:2-500, preferably 1:5-250, more preferably 1:15-50.

12. according to the method described in claim 10 or 11, wherein, nitrogen-containing compound: the mol ratio of peroxide is 1:0.001-10, preferably 1:0.002-5, more preferably 1:0.05-2.

13. according to the method described in any one in claim 10-12, and wherein, described peroxide is selected from the organic peroxide shown in hydrogen peroxide and Formulas I,

In Formulas I, R₁And R₂It each is selected from H, C₄-C₁₂Straight or branched alkyl, C₆-C₁₂Aryl, C₇-C₁₂Aralkyl andAnd R₁And R₂It is asynchronously H, R₃For C₄-C₁₂Straight or branched alkyl or C₆-C₁₂Aryl；

Preferably, described peroxide is selected from hydrogen peroxide, tert-butyl hydroperoxide, cyclohexyl hydroperoxide, cumyl peroxide, cumyl hydroperoxide and dibenzoyl peroxide.

14. methods according to claim 10, wherein, described nitrogen-containing compound is NH₃Described peroxide is selected from hydrogen peroxide, raw material nano material with carbon element: nitrogen-containing compound: the weight ratio of peroxide is 1:0.02-5:0.01-5, it is preferably 1:0.02-2.5:0.1-5, more preferably 1:0.1-2:0.4-4.5, more preferably 1:0.2-0.5:0.5-1, nitrogen-containing compound is 1:0.02-2 with the mol ratio of peroxide, it is preferably 1:0.1-1.8, more preferably 1:1-1.5；Or

Described nitrogen-containing compound is hydrazine, described peroxide is selected from tert-butyl hydroperoxide, raw material nano material with carbon element: nitrogen-containing compound: the weight ratio of peroxide is 1:0.02-5:0.01-8, more preferably 1:0.08-3:0.02-5, more preferably 1:0.1-0.5:0.1-1, nitrogen-containing compound is 1:0.001-8, preferably 1:0.003-6, more preferably 1:0.1-0.5 with the mol ratio of peroxide；Or

Described nitrogen-containing compound is carbamide, described peroxide is selected from cumyl hydroperoxide, raw material nano material with carbon element: nitrogen-containing compound: the weight ratio of peroxide is 1:0.02-5:0.01-3, it is preferably 1:0.05-2:0.05-2, more preferably 1:0.2-0.5:0.1-1, nitrogen-containing compound is 1:0.005-4, preferably 1:0.05-2 with the mol ratio of peroxide.

15. according to the method described in any one in claim 10-14, and wherein, in course of reaction, the temperature of described aqueous dispersions is maintained in the range of 100-180 DEG C.

16. according to the method described in any one in claim 10-15, wherein, the persistent period of described reaction in the range of 0.5-96 hour, preferably in the range of 2-72 hour, more preferably in the range of 20-50 hour.

17. according to the method described in any one in claim 10-16, wherein, in described raw material nano material with carbon element, the content of N element is not higher than 0.5 weight %, preferably not higher than 0.2 weight %, more preferably not above 0.1 weight %, the most not higher than 0.05 weight %；The content of O element is not higher than 1.2 weight %, preferably not higher than 0.5 weight %.

18. according to the method described in any one in claim 10-17, and wherein, described raw material nano material with carbon element is CNT；Preferably, described raw material nano material with carbon element is multi-walled carbon nano-tubes.

19. methods according to claim 18, wherein, the specific surface area of described multi-walled carbon nano-tubes is 20-500m²/ g, preferably 50-300m²/ g, more preferably 80-250m²/ g, more preferably 90-150m²/g。

20. according to the method described in claim 18 or 19, and wherein, described multi-walled carbon nano-tubes weight-loss ratio in the temperature range of 400-800 DEG C is w₈₀₀, the weight-loss ratio in the temperature range of 400-500 DEG C is w₅₀₀, w₅₀₀/w₈₀₀In the range of 0.01-0.5, preferably in the range of 0.02-0.2, described weight-loss ratio measures in air atmosphere.

21. according to the method described in any one in claim 10-20, and wherein, the method also includes isolating solid matter from the mixture that reaction obtains, and is dried by isolated solid matter.

22. methods according to claim 21, wherein, described being dried is carried out at a temperature of 50-200 DEG C, preferably carries out at a temperature of 80-180 DEG C, more preferably carries out at a temperature of 120-150 DEG C；The described dry persistent period is 0.5-48 hour, preferably 3-24 hour, more preferably 5-12 hour.

23. 1 kinds by the method described in any one in claim 10-22 prepare containing hetero atom nano-carbon material.

24. 1 kinds of nano-carbon materials Han hetero atom, this contain hetero atom nano-carbon material be by described in any one in claim 1-9 containing carrying out roasting and prepared containing hetero atom nano-carbon material described in hetero atom nano-carbon material or claim 23.

25. is according to claim 24 containing hetero atom nano-carbon material, and wherein, described roasting is carried out at a temperature of 250-500 DEG C, preferably carries out at a temperature of 300-450 DEG C；The persistent period of described roasting is 1-24 hour, preferably 2-12 hour.

In 26. claim 1-9 and 23 described in any one containing described in any one in hetero atom nano-carbon material or claim 24-25 containing hetero atom nano-carbon material as the application of the catalyst of hydrocarbon dehydrogenation reaction.

27. application according to claim 26, wherein, described dehydrogenation reaction is carried out in the presence of oxygen.

28. according to the application described in claim 26 or 27, and wherein, described hydrocarbon is alkane, preferably C₂-C₁₂Alkane, more preferably normal butane.

29. 1 kinds of hydrocarbon dehydrogenation reaction methods, under conditions of the method is included in presence or absence oxygen, under hydrocarbon dehydrogenation reaction conditions, by hydrocarbon and contacting containing the nano-carbon material containing hetero atom described in any one in hetero atom nano-carbon material or claim 24-25 described in any one in claim 1-9 and 23.

30. methods according to claim 29, wherein, described hydrocarbon is alkane, preferably C₂-C₁₂Alkane, more preferably normal butane.