CN109201076B - Composition capable of reducing CO and NOx emission, preparation method and application thereof, and fluidized catalytic cracking method - Google Patents

Abstract

The invention relates to the field of catalytic cracking, and discloses a composition capable of reducing CO and NOx emission, a preparation method and application thereof, and a fluidized catalytic cracking method, wherein the composition capable of reducing CO and NOx emission provided by the invention comprises the following components: the inorganic oxide carrier and a first metal element and a second metal element loaded on the inorganic oxide carrier, wherein the first metal element comprises Fe and Co, and the weight ratio of Fe to Co is 1: (0.1-10). The composition Fe and Co provided by the invention are jointly used as main metal elements, and the composition can be kept to have higher hydrothermal stability through further modification of at least one of IB-VIIB group non-noble metal elements, and has higher activity of reducing CO and NOx emission of regenerated flue gas.

Description

Compositions capable of reducing CO and NOx emissions, methods for their preparation and applications, and methods for fluid catalytic cracking

technical field

The present invention relates to the field of catalytic cracking, in particular to a composition capable of reducing CO and NOx emissions, a method for preparing the composition capable of reducing CO and NOx emissions, and a composition capable of reducing CO and NOx emissions prepared by the method, and the above-mentioned compositions capable of reducing CO and NOx emissions. Use of a composition for reducing CO and NOx emissions and a fluid catalytic cracking process.

Background technique

The rising price of crude oil has greatly increased the processing cost of refineries. On the one hand, refineries reduce costs by purchasing low-priced and inferior oil; on the other hand, they increase economic benefits by in-depth processing of heavy oil. Catalytic cracking, as an important means of heavy oil processing in refineries, plays an important role in refineries. It is not only the main means of heavy oil balance and clean fuel production in refineries, but also the focus of energy conservation and efficiency enhancement in refineries. Catalytic cracking is a fast catalytic reaction system with rapid catalyst deactivation, and solving the problem of catalyst regeneration has always been the main line of catalytic cracking development.

In the process of fluid catalytic cracking (FCC), the feedstock oil and the regenerated catalyst are rapidly contacted in the riser to carry out the catalytic cracking reaction, and the coke generated by the reaction is deposited on the catalyst to cause its deactivation. A regenerator, which is in contact with the regeneration air or oxygen-enriched air entering the bottom of the regenerator for scorch regeneration. The regenerated catalyst is recycled back to the reactor to participate in the catalytic cracking reaction again. According to the level of excess oxygen content in the flue gas or the sufficient degree of CO oxidation during the regeneration process, the catalytic cracking unit can be divided into complete regeneration and incomplete regeneration operations.

During the complete regeneration process, the coke and the nitrogen-containing compounds in the coke generate CO ₂ and N ₂ under the action of the regeneration air, and also produce pollutants such as CO and NOx. The use of catalytic promoters is an important technical measure to control CO and NOx emission pollution.

The adjuvant used to reduce the CO emission of the regenerated flue gas is usually referred to as a CO combustion accelerant. For example, CN1022843C discloses a noble metal supported carbon monoxide combustion accelerant, the active component of which is 1-1000ppm platinum or 50-1000ppm palladium, and the carrier is composed of (1 ) 99.5-50% of cracking catalyst or microsphere particles of its matrix and (2) 0.5-50% Al ₂ O ₃ , 0-20% RE ₂ O ₃ and 0-15% ZrO ₂ composition, (2) is ( 1) The outer coating of the particles.

Adjuvants used to control flue gas NOx emissions are commonly referred to as NOx reduction aids or NOx reduction aids, for example CN102371150A discloses a non-precious metal composition for reducing NOx emissions from catalytic cracking regeneration flue gas, the composition The bulk ratio does not exceed 0.65 g/ml, based on the weight of the composition, and contains, in terms of oxide: (1) 50-99 wt % inorganic oxide carrier, (2) 0.5-40 wt % optional One or several non-noble metal elements from groups IIA, IIB, IVB and VIB, and (3) 0.5-30 wt% rare earth elements. The composition is used in fluid catalytic cracking and can significantly reduce NOx emissions from regeneration flue gas.

There is also a class of additives that can simultaneously reduce CO and NOx emissions from regenerated flue gas, and can take into account both CO combustion support and NOx emission reduction. With the increasingly strict environmental regulations, the application of such additives is becoming more and more common. For example, CN1688508A discloses a composition for reducing NOx and CO emissions from fluidized catalytic cracking flue gas and its application, the composition comprising copper and/or cobalt and a carrier selected from the group consisting of hydrotalcite compounds, sharp Spar, alumina, zinc titanate, zinc aluminate, zinc titanate/zinc aluminate. CN102371165A discloses a low stack ratio composition for reducing CO and NOx emissions from FCC regeneration flue gas, the composition contains rare earth elements and one or several non-precious metal elements, preferably the non-precious metals are supported on Y-type zeolite. US6165933 discloses a CO combustion-supporting composition (co-agent) for reducing NOx emissions from a catalytic cracking process, the composition comprising: (i) an acidic metal oxide substantially free of zeolite; (ii) an alkali metal, alkaline earth metal or is a mixture thereof; (iii) an oxygen storage component and (iv) palladium, the inorganic oxide support is preferably silica-alumina, and the oxygen storage transition metal oxide is preferably ceria. US7045056 discloses a composition for simultaneously reducing CO and NOx emissions from a catalytic cracking process flue gas, the composition comprising: (i) an inorganic oxide support; (ii) an oxide of cerium; (iii) a a lanthanide oxide other than cerium, wherein the weight ratio of (ii) to (iii) is at least 1.66:1; (iv) optionally a Group IB and IIB transition metal oxide, and (v) at least one a precious metal element. CN105363444A discloses a composition for reducing CO and NOx emissions from FCC regeneration flue gas and a preparation method thereof, the composition contains in terms of oxides: (1) 0.5-30 wt% rare earth elements, (2) 0.01 -0.15% by weight of precious metal elements, and (3) the balance of an inorganic oxide support that is substantially free of alkali metals and alkaline earth metals; in the preparation method, the composition after the introduction of precious metals is subjected to alkaline treatment before drying and/or calcination Solution treatment, the disclosed composition is used for fluidized catalytic cracking, which can effectively avoid "after-burning" caused by excessively high CO concentration in the regenerated flue gas, can effectively control the emission concentration of CO and NOx in the regenerated flue gas, and significantly reduce the smoke Gas NOx emissions, basically no adverse effect on the distribution of FCC products.

During the incomplete regeneration process, due to the low excess oxygen content and high CO concentration in the flue gas, the NOx concentration in the flue gas at the regenerator outlet is very low, while the concentration of reduced nitrogen compounds such as NH ₃ and HCN is high. These reduced nitrogens flow downstream with the flue gas. In the CO boiler used for energy recovery, if they are fully oxidized, NOx will be generated; if they are not fully oxidized, the remaining NH ₃ will easily cause downstream scrubber wastewater. Ammonia nitrogen exceeds the standard, or reacts with SO _x in the flue gas to form ammonium salts, which will cause salt formation in the residual boiler or other flue gas post-processing equipment (such as SCR), which will affect the long-term operation of the device. Therefore, the incomplete regeneration process uses catalytic promoters to catalytically convert NH ₃ and other substances in the regenerator, which can reduce the NOx emission in the flue gas and prolong the operation period of the device.

US5021144 discloses a method for reducing _NH3 emission in flue gas of incompletely regenerated FCC unit. The method is to add excess CO combustion-supporting agent in the regenerator, and the addition amount is the minimum addition amount that can prevent tail-burning in the dilute phase bed. 2-3 times. Although this method can reduce the _NH3 emission in the flue gas of the incompletely regenerated FCC unit, the amount of CO used is relatively large, which has the disadvantage of high energy consumption, and is not conducive to environmental protection.

US4755282 discloses a method for reducing _NH3 emissions in the flue gas of a partially regenerated or incompletely regenerated FCC unit. This method converts _NH3 into _N2 and water by adding ammonia decomposition catalyst with a particle size of 10-40 μm into the regenerator to maintain a certain concentration in the dilute phase bed. The active component of the ammonia decomposition catalyst may be a noble metal dispersed on an inorganic oxide support.

CN101024179A discloses a NOx reducing composition for use in an FCC process comprising (i) an acidic metal oxide substantially free of zeolite, (ii) alkali metals, alkaline earth metals and mixtures thereof and (iii) Oxygen storage components. The prepared composition is impregnated with precious metal to convert gas-phase reduced nitrogen substances in flue gas of incomplete regeneration catalytic cracking unit, and reduce NOx emission of flue gas.

At present, there are relatively few reports on the research and application of adjuvant technology for controlling the emission of _NH3 and NOx in the flue gas of the incomplete regeneration device. Since the flue gas composition of the incomplete regeneration device is significantly different from that of the complete regeneration device, the existing ones are suitable for the complete regeneration device. The application effect of the incomplete regeneration device is not ideal. Although the adjuvant compositions disclosed in the above technologies can catalytically convert reduced nitrogen compounds such as NH _{3 in flue gas to a certain extent, the catalytic conversion activity of NH 3 and} other reduced nitrogen compounds in flue gas still needs to be improved to slow down. The impact of NH ₃ and other deposited salts on the operation of the equipment requires the development of flue gas pollutant emission reduction aids suitable for incomplete regeneration devices to further reduce flue gas NOx emissions.

SUMMARY OF THE INVENTION

Aiming at the defect of low catalytic conversion activity of _NH3 and other reduced nitrogen compounds in the regeneration process of the prior art, the present invention provides a new composition capable of reducing CO and NOx emissions, and a composition capable of reducing CO and NOx emissions A preparation method and a composition capable of reducing CO and NOx emissions prepared by the method, application of the above-mentioned composition capable of reducing CO and NOx emissions in flue gas treatment, and a fluidized catalytic cracking method. The composition capable of reducing CO and NOx emissions provided by the invention has high catalytic conversion activity to reduced nitrogen compounds, and the preparation method is simple, and can be used in the fluidized catalytic cracking process, and can effectively reduce CO and NOx in the catalytic cracking regeneration flue gas Emissions, the compositions provided by the present invention capable of reducing CO and NOx emissions are particularly suitable for incomplete regeneration flue gas treatment processes.

The inventors of the present invention found in the research process that inorganic oxides are used as carriers, and a group VIII non-precious metal element containing Fe and Co is used in combination with at least one of the group IB-VIIB non-precious metal elements as an active component, It can effectively reduce CO and NOx emissions in the catalytic cracking regeneration flue gas. It is speculated that the reason may be due to: Fe and Co are used together as the main metal elements to produce a certain synergistic effect, and further modification by at least one of the non-precious metal elements of Group IB-VIIB is beneficial to reduce the oxidation state of nitrogen-containing compounds. and can promote the decomposition of reduced nitrogen-containing compounds.

Through further research, it is found that in a preferred case, after spray drying, the solid material obtained after spray drying is treated at a high temperature in a carbon-containing atmosphere, which can more effectively reduce the emissions of CO and NOx from the catalytic cracking regeneration flue gas. In the above preferred case, the structure of the composition capable of reducing CO and NOx emissions is further modulated and stabilized, so that the composition capable of reducing CO and NOx emissions has an obvious catalytic conversion activity to NH ₃ and other reduced nitrogen compounds It has better hydrothermal stability and meets the requirements of the regenerator hydrothermal environment for a composition capable of reducing CO and NOx emissions.

Based on this, according to a first aspect of the present invention, there is provided a composition capable of reducing CO and NOx emissions, the composition comprising: an inorganic oxide carrier and a first metal element and a second metal supported on the inorganic oxide carrier element, the first metal element is selected from the group VIII non-noble metal elements, and the first metal element includes Fe and Co, in terms of oxides, the weight ratio of Fe to Co is 1: (0.1-10), so The second metal element is at least one selected from the group IB-VIIB non-noble metal elements.

According to a second aspect of the present invention, there is provided a method for preparing a composition capable of reducing CO and NOx emissions, the method comprising:

Mixing and beating the precursor of the inorganic oxide carrier, the precursor of the first metal element, the precursor of the second metal element and water to obtain a slurry, spray-drying the slurry, and then calcining;

Wherein, the first metal element is selected from Group VIII non-noble metal elements, and the first metal element includes Fe and Co; the second metal element is selected from at least one of Group IB-VIIB non-noble metal elements;

Wherein, in the first metal element precursor, the amount of Fe precursor and Co precursor is such that, in the obtained composition, in terms of oxide, the weight ratio of Fe to Co is 1:(0.1-10).

According to a third aspect of the present invention, there is provided a composition capable of reducing CO and NOx emissions prepared by the above preparation method.

According to a fourth aspect of the present invention, there is provided the use of the above-mentioned composition capable of reducing CO and NOx emissions in flue gas treatment.

According to a fifth aspect of the present invention, there is provided the application of the above-mentioned composition capable of reducing CO and NOx emissions in the treatment of catalytic cracking regeneration flue gas.

According to a sixth aspect of the present invention, a fluidized catalytic cracking method is provided, the method comprising: contacting and reacting hydrocarbon oil with a catalyst, and then regenerating the catalyst after the contact reaction, the catalyst comprising a catalytic cracking catalyst and a catalyst capable of reducing CO and a composition for reducing CO and NOx emission, the composition capable of reducing CO and NOx emission is the above-mentioned composition capable of reducing CO and NOx emission of the present invention.

The composition capable of reducing CO and NOx emission provided by the present invention can be used as a catalytic cracking aid, can maintain high hydrothermal stability in the hydrothermal environment of the regenerator, and has high CO and NOx emission reduction activity of regeneration flue gas. In addition, the preparation method of the composition capable of reducing CO and NOx emission provided by the present invention is simple in operation and low in production cost. Compared with the FCC method using the existing CO and NOx emission reduction aids, the FCC method using the composition capable of reducing CO and NOx emission provided by the present invention, the amount of the composition capable of reducing CO and NOx emission is low, and the CO and higher NOx emission activity.

For example, the composition capable of reducing CO and NOx emissions provided in Example 3 of the present invention is uniformly blended with the FCC main catalyst (Cat-A) in a proportion of 0.8 wt % of the total weight of the catalyst, and heated at 800° C. and 100% water. Catalytic cracking reaction-regeneration evaluation is carried out after aging in a steam atmosphere for 12 hours. Compared with the composition D-3 which can reduce CO and NOx emissions prepared by the active component saturated impregnation method in the prior art, the use of the composition provided by the present invention can reduce the CO and NOx emissions. Combination of CO and NOx emissions, the NOx emission concentration in the incompletely regenerated flue gas under aerobic conditions was reduced from 109 ppm to 55 ppm.

Other features and advantages of the present invention will be described in detail in the detailed description that follows.

Description of drawings

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

FIG. 1 is the XRD patterns of the compositions prepared in Example 1 and Example 5 capable of reducing CO and NOx emissions.

Detailed ways

The endpoints of ranges and any values disclosed herein are not limited to the precise ranges or values, which are to be understood to encompass values proximate to those ranges or values. For ranges of values, the endpoints of each range, the endpoints of each range and the individual point values, and the individual point values can be combined with each other to yield one or more new ranges of values that Ranges should be considered as specifically disclosed herein.

The present invention provides a composition capable of reducing CO and NOx emissions, the composition comprising: an inorganic oxide support and a first metal element and a second metal element supported on the inorganic oxide support, the first metal element is selected from the group VIII non-noble metal elements, and the first metal element includes Fe and Co, in terms of oxides, the weight ratio of Fe to Co is 1: (0.1-10), and the second metal element is selected from the At least one of the non-precious metal elements of Group IB-VIIB.

In the present invention, the content of the first metal element and the second metal element in the composition has a wide selection range, preferably, based on the total amount of the composition, the content of the inorganic oxide carrier is 50-90% % by weight, in terms of oxides, the content of the first metal element is 3-30% by weight, and the content of the second metal element is 1-20% by weight; further preferably, the content of the inorganic oxide carrier is 60-90% by weight, in terms of oxide, the content of the first metal element is 5-25% by weight, and the content of the second metal element is 2-15% by weight; more preferably, the inorganic The content of the oxide support is 76-86 wt %, the content of the first metal element is 10-16 wt %, and the content of the second metal element is 2-8 wt % in terms of oxide.

The first metal element of the present invention includes Fe and Co, and the present invention does not exclude that the first metal element also contains elements other than Fe and Co in the Group VIII non-noble metal elements, such as Ni.

According to a most preferred embodiment of the present invention, the composition consists of an inorganic oxide support and a first metal element and a second metal element supported on the inorganic oxide support, and the first metal element is only Fe and Co .

In the present invention, as long as Fe and Co are contained in the first metal element, the catalytic conversion activity of the composition to reduced nitrides such as NH ₃ can be improved. , the weight ratio of Fe to Co is 1:(0.3-3), more preferably 1:(0.5-2).

In the present invention, unless otherwise specified, Fe is calculated as an oxide means that Fe is calculated as Fe ₂ O ₃ , and Co is calculated as an oxide means that Co is calculated as Co ₂ O ₃ .

According to a preferred embodiment of the present invention, Fe in the composition at least partially exists in the form of iron carbide, preferably, the iron carbide is Fe ₃ C and/or Fe ₇ C ₃ . The amount of iron carbide present is not particularly limited in the present invention, as long as a part of iron carbide is present, the performance of the composition capable of reducing CO and NOx emissions can be effectively improved.

According to a preferred embodiment of the present invention, the Co in the composition is at least partially present in the form of elemental cobalt. The present invention has no particular limitation on the amount of elemental cobalt present, as long as a part of elemental cobalt is present, the performance of the composition capable of reducing CO and NOx emissions can be effectively improved.

It should be noted that, in the existing compositions for reducing CO and NOx emissions, most of the metal elements in the compositions exist in an oxidized form. In the preparation process of the composition of the present invention, preferably after spray drying, it is calcined in a carbon-containing atmosphere, so that part of FeO is converted into iron carbide, and part of CoO is converted into elemental cobalt.

The presence of iron carbide and/or elemental cobalt enables the composition to better promote the decomposition of reduced nitrogen-containing compounds, reduce the generation of nitrogen oxides, and promote the reduction of nitrogen oxides to a certain extent.

According to the composition provided by the present invention, preferably, in the XRD pattern of the composition, there are diffraction peaks at 2θ of 42.6°, 44.2° and 44.9°.

Specifically, the diffraction peaks of iron carbide at 2θ of 42.6° and 44.9° are the diffraction peaks of elemental cobalt at 2θ of 44.2°.

According to a preferred embodiment of the present invention, in the XRD pattern of the composition provided by the present invention, the diffraction peak at 2θ of 44.9° is stronger than the diffraction peak at 2θ of 42.6°.

According to the composition provided by the present invention, the inorganic oxide carrier can be various inorganic oxide carriers conventionally used in the art, such as selected from alumina, silica-alumina, zeolite, spinel, kaolin, diatom At least one of soil, perlite and perovskite. In the present invention, the spinel may be various commonly used spinels, for example, may be at least one of magnesium aluminum spinel, zinc aluminum spinel and titanium aluminum spinel.

According to a preferred embodiment of the present invention, the inorganic oxide support is selected from at least one of alumina, spinel and perovskite, and is more preferably alumina.

In the present invention, the alumina may be selected from at least one of γ-alumina, δ-alumina, η-alumina, ρ-alumina, κ-alumina, and χ-alumina, and the present invention is aimed at this There is no particular limitation.

The alumina can be derived from various sols or gels of aluminum, or aluminum hydroxide. The aluminum hydroxide may be selected from at least one of gibbsite, pyrenite, nordishite, diaspore, boehmite, and pseudo-boehmite. Preferably the alumina is derived from pseudoboehmite.

The above-mentioned inorganic oxide supports are commercially available, and can also be prepared by using existing methods.

In the present invention, the non-noble metal elements of Group IB-VIIB refer to the non-noble metals from Group IB to Group VIIB in the periodic table, including Group IB non-noble metals, Group IIB metals, Group IIIB metals, and Group IVB metal, Group VB metal, Group VIB metal and Group VIIB metal, specifically, the non-noble metal elements of Group IB-VIIB include but are not limited to Cu, Zn, Cd, Sc, Y, Ti, Zr, At least one of V, Nb, Cr, Mo, W, Mn, Re, and rare earth elements; the rare earth elements include but are not limited to at least one of La, Ce, Pr, Nd, Pm, Sm, and Eu.

According to the composition provided by the present invention, preferably the second metal element is selected from at least one of Cu, Zn, Ti, Zr, V, Cr, Mo, W, Mn and rare earth elements, preferably Zr, V, W At least one of , Mn, Ce and La, most preferably Mn.

According to a most preferred embodiment of the present invention, the use of Fe, Co and Mn as metal elements can greatly improve the catalytic conversion activity of the composition capable of reducing CO and NOx emissions to NH ₃ and other reduced nitrides, And the composition capable of reducing CO and NOx emissions has more excellent hydrothermal stability performance.

According to a specific embodiment of the present invention, the composition comprises: alumina and Fe, Co and Mn supported on the alumina, in terms of oxides, the weight ratio of Fe to Co is 1:(0.5-2), Based on the total amount of the composition, the content of alumina is 76-86 wt %, the total content of Fe and Co is 10-16 wt %, and the content of Mn is 2-8 wt % in terms of oxides. The composition has higher catalytic conversion activity and hydrothermal stability to reduced nitrogen compounds such as _NH3 .

In the present invention, the content of each component in the composition capable of reducing CO and NOx emissions is measured by X-ray fluorescence spectroscopic analysis method (Petrochemical Analysis Method (RIPP Experimental Method), edited by Yang Cuiding et al., published by Science Press in 1990). .

The present invention also provides a method for preparing a composition capable of reducing CO and NOx emissions, the method comprising:

Mixing and beating the precursor of the inorganic oxide carrier, the precursor of the first metal element, the precursor of the second metal element and water to obtain a slurry, spray-drying the slurry, and then calcining;

Wherein, the first metal element is selected from Group VIII non-noble metal elements, and the first metal element includes Fe and Co; the second metal element is selected from at least one of Group IB-VIIB non-noble metal elements;

Wherein, in the first metal element precursor, the amount of Fe precursor and Co precursor is such that, in the obtained composition, in terms of oxide, the weight ratio of Fe to Co is 1:(0.1-10).

In the present invention, the precursor of the inorganic oxide carrier includes various substances that can obtain the inorganic oxide carrier through subsequent calcination treatment, which is not particularly limited in the present invention.

According to the preparation method provided by the present invention, the selection of the inorganic oxide carrier, the first metal element and the second metal element is as described above, and details are not repeated here.

In the present invention, the precursor of alumina can be selected from various sols or gels of aluminum, or aluminum hydroxide. The aluminum hydroxide may be selected from at least one of gibbsite, pyrenite, nordishite, diaspore, boehmite, and pseudo-boehmite. Most preferably, the alumina precursor is pseudoboehmite.

According to the preparation method provided by the present invention, preferably, before beating, the alumina precursor is subjected to acidification peptization treatment, and the acidification peptization treatment can be carried out according to conventional technical means in the art. Further preferably, the acidified glue The acid used for the dissolution treatment was hydrochloric acid.

The present invention has a wide selection range for the conditions of the acidified peptization treatment. Preferably, the conditions of the acidified peptization treatment include: the acid-aluminum ratio is 0.12-0.22:1, and the time is 20-40 min.

In the present invention, unless otherwise specified, the acid-aluminum ratio refers to the mass ratio of hydrochloric acid based on 36% by weight of concentrated hydrochloric acid to the precursor of alumina based on dry basis.

The specific embodiment of the acidified peptizing treatment may be as follows: adding pseudo-boehmite to water for beating and dispersion, then adding hydrochloric acid for acidification for 30 minutes, and the acid-aluminum ratio is 0.18.

According to the present invention, the first metal element precursor and the second metal element precursor are respectively selected from water-soluble salts of the first metal element and the second metal element, such as nitrate, chloride, chlorate or sulfate, etc. , which is not particularly limited in the present invention.

According to the preparation method of the present invention, the selection range of the amount of the first metal element precursor and the second metal element precursor is wide, preferably, the precursor of the inorganic oxide carrier, the first metal element The amount of the precursor and the second metal element precursor is such that, in the prepared composition, based on the total amount of the composition, the content of the inorganic oxide carrier is 50-90% by weight, calculated as oxide, so The content of the first metal element is 3-30% by weight, and the content of the second metal element is 1-20% by weight; further preferably, the content of the inorganic oxide carrier is 60-90% by weight, so as to oxidize In terms of material, the content of the first metal element is 5-25% by weight, and the content of the second metal element is 2-15% by weight; more preferably, the content of the inorganic oxide carrier is 76-86% % by weight, in terms of oxides, the content of the first metal element is 10-16% by weight, and the content of the second metal element is 2-8% by weight.

For the preparation method of the composition capable of reducing CO and NOx emissions provided by the present invention, preferably, the precursor of the inorganic oxide carrier in terms of oxide, the first metal element precursor in terms of Group VIII non-noble metal element oxide And the amount-to-mass ratio of the second metal element precursor based on the non-precious metal element oxide of Group IB-VIIB is 50-90:3-30:1-20; further, it can be 60-90:5-25: 2-15, and further, 76-86:10-16:2-8.

In the present invention, the first metal element precursor includes at least a Fe precursor and a Co precursor.

According to a preferred embodiment of the present invention, in the precursor of the first metal element, the amount of the Fe precursor and the Co precursor is such that, in the obtained composition, in terms of oxides, the weight ratio of Fe to Co is preferably It is 1:(0.3-3), More preferably, it is 1:(0.5-2).

According to the present invention, it is preferred that the solid content of the slurry is 8-30% by weight.

According to the present invention, the method for mixing and beating the precursor of the inorganic oxide carrier, the precursor of the first metal element, the precursor of the second metal element and water is not particularly limited. The order of adding the precursor of a metal element and the precursor of the second metal element is also not limited, as long as the precursor of the inorganic oxide carrier, the precursor of the first metal element and the precursor of the second metal element and water are contacted, preferably , dissolve the first metal element precursor and the second metal element precursor in water, then add a precursor of an inorganic oxide carrier (preferably an acidified precursor of an inorganic oxide carrier), and then beat to obtain a slurry.

In the present invention, the spray drying can be performed according to conventional technical means in the field, which is not particularly limited in the present invention. The range is mainly 20-100 μm, and further preferably, the conditions of spray drying are such that among the particles obtained by spray drying, particles with a particle size of 40-80 μm account for more than 50%.

According to the present invention, the calcination can effectively improve the catalytic conversion activity of the composition capable of reducing CO and NOx emissions to NH ₃ and other reduced nitrogen compounds by using conventional technical means in the field, but in order to further improve the ability to reduce CO and NOx emissions The catalytic conversion activity and hydrothermal stability of the composition to reduced nitrides such as _NH3 , preferably the calcination is carried out in a carbon-containing atmosphere. The inventors of the present invention have unexpectedly discovered during the research process that carrying out the calcination in a carbon-containing atmosphere can enable the catalytic conversion activity and hydrothermal activity of the composition capable of reducing CO and NOx emissions to reduced nitrides such as _NH3 The stability is obviously improved, and the calcination in a carbon-containing atmosphere is more conducive to adjusting the relationship between each active metal component and the carrier. The improvement of the activity is related to the conversion of the active components from oxides to carbides and the reduced state, and the improvement of hydrothermal stability may be related to the carbon-containing high temperature treatment which further promotes the bonding, fusion and cross-linking of the active components in the composition. related. It can be seen from the XRD comparison spectrum that there are obvious peaks of iron carbide and elemental cobalt after treatment. Specifically, as shown in FIG. 1 , the XRD spectrum of composition S-5 without carbon-containing atmosphere treatment has diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ at about 45.3°, while the XRD spectrum of composition S-5 without carbon-containing atmosphere treatment In the XRD spectrum of the treated composition S-1, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ around 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, and the 2θ is 42.6°, The diffraction peak at 44.9° is that of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-1 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-1 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In the composition S-1 treated with a carbon-containing atmosphere, part of the cobalt oxide was converted into elemental cobalt.

It should be noted that FIG. 1 only lists the XRD patterns in the range of 41°-50°, which are mainly used to illustrate the existence forms of Fe and Co in the composition. Outside the range of 41°-50°, there are other diffraction peaks, such as those of FeO (at 37°, 65° and 59° in 2θ) and CoO (at 37°, 65° and 31° in 2θ) , the present invention does not further explain this.

According to a preferred embodiment of the present invention, the calcination conditions include: in a carbon-containing atmosphere, the temperature is 400-1000°C, preferably 450-650°C, more preferably 500-650°C, and the time is 0.1- 10h, preferably 1-3h.

In the present invention, the pressure of the first calcination is not particularly limited, and it can be carried out under normal pressure. For example, it can be carried out at 0.01-1 Mpa (absolute pressure).

In the present invention, the carbon-containing atmosphere is provided by a gas containing carbon-containing elements, and the carbon-containing element-containing gas is preferably selected from reducing carbon-containing element gases, more preferably containing CO, methane and ethane. At least one, most preferably CO.

According to the present invention, the carbon-containing gas may also contain a part of inert gas, and the inert gas may be various inert gases conventionally used in the field. Preferably, the inert gas is selected from nitrogen, argon and helium. At least one of them is more preferably nitrogen.

According to a preferred embodiment of the present invention, the carbon-containing atmosphere is provided by a mixed gas containing CO and nitrogen, and the volume concentration of CO in the carbon-containing atmosphere is preferably 1-20%, more preferably 4-10%. By adopting the preferred embodiment of the present invention, not only the processing requirements can be better met, but also the safety of operators can be ensured.

In the present invention, the roasting can be carried out in a roasting furnace, and the roasting furnace can be a rotary roasting furnace used in the production of catalytic cracking catalysts and auxiliary agents. The carbon-containing gas is brought into countercurrent contact with the solid material in the roaster in the roaster.

The present invention also provides a composition capable of reducing CO and NOx emissions prepared by the above preparation method.

The composition capable of reducing CO and NOx emissions prepared by the above preparation method contains at least one of Fe and Co and Group IB-VIIB non-precious metal elements, and the above-mentioned metal elements are used in combination, so that CO and NOx emissions can be reduced. The catalytic conversion activity of the composition to reduced nitrogen such as NH ₃ is significantly improved, and the composition capable of reducing CO and NOx emissions has better hydrothermal stability.

The present invention also provides the application of the above-mentioned composition capable of reducing CO and NOx emissions in flue gas treatment. The compositions provided by the present invention can be used to treat any flue gas that needs to reduce CO and NOx emissions.

The present invention also provides the application of the above-mentioned composition capable of reducing CO and NOx emissions in the treatment of catalytic cracking regeneration flue gas. The above-mentioned composition capable of reducing CO and NOx emissions is particularly suitable for reducing CO and NOx emissions in fully regenerated flue gas and incompletely regenerated flue gas, and the composition capable of reducing CO and NOx emissions provided by the present invention is more suitable for reducing incompletely regenerated flue gas. Emissions of CO and NOx in the regeneration flue gas. Accordingly, the present invention provides the use of the above-mentioned composition capable of reducing CO and NOx emissions in the treatment of incompletely regenerated flue gas from catalytic cracking.

The present invention also provides a fluidized catalytic cracking method, which comprises: contacting and reacting hydrocarbon oil with a catalyst, and then regenerating the catalyst after the contact reaction, the catalyst comprising a catalytic cracking catalyst and a catalyst capable of reducing CO and NOx emissions The composition, the composition capable of reducing CO and NOx emission is the above-mentioned composition capable of reducing CO and NOx emission of the present invention.

According to the fluidized catalytic cracking method provided by the present invention, preferably, based on the total amount of catalyst, the content of the composition capable of reducing CO and NOx emissions is 0.05-5 wt %, more preferably 0.1-3 wt % , more preferably 0.5-2.5% by weight.

According to the fluidized catalytic cracking method provided by the present invention, preferably, the hydrocarbon oil is contacted and reacted with the catalyst, and then the catalyst after the contact reaction is subjected to incomplete regeneration. Further preferably, the oxygen in the flue gas generated by the incomplete regeneration is The concentration is not more than 0.5% by volume.

The hydrocarbon oil is not particularly limited in the present invention, and can be various hydrocarbon oils conventionally treated in the field of catalytic cracking, such as vacuum gas oil, atmospheric residual oil, vacuum residual oil, deasphalted oil, coking wax oil or added oil. Hydrogen treated oil.

The catalytic cracking catalyst is not particularly limited in the present invention, and can be one or more of the existing catalytic cracking catalysts, which can be purchased commercially or prepared according to existing methods.

The compositions provided by the present invention capable of reducing CO and NOx emissions may be a separate particle, or may be an integral part of the catalytic cracking catalyst particle. Preferably, the composition for reducing CO and NOx emissions provided by the present invention is used as a separate particle in combination with catalytic cracking catalyst particles.

In the present invention, unless otherwise specified, the ppm refers to volume concentration.

In the fluid catalytic cracking method of the present invention, the catalyst regeneration method has no special requirements compared with the existing regeneration methods, including partial regeneration, incomplete regeneration and complete regeneration operation modes. For the regeneration method, please refer to pages 1234-1343 of Catalytic Cracking Technology and Engineering, edited by Chen Junwu and published by China Petrochemical Press in 2005. The preferred regeneration temperature is 650°C to 730°C.

The implementation process and the beneficial effects of the present invention are described in detail below through specific examples, which are intended to help readers understand the spirit and essence of the present invention more clearly, but cannot constitute any limitation on the implementation scope of the present invention.

In the following examples, the content of the components in the compositions capable of reducing CO and NOx emissions were all determined by X-ray fluorescence spectroscopy (XRF) method. For details, please refer to the analysis method of petrochemical industry (RIPP experimental method), edited by Yang Cuiding et al., Science Press, 1990 publishing. The compositions capable of reducing CO and NOx emissions in the examples were obtained by using an X-ray diffractometer (Siemens D5005 model) to obtain XRD patterns for structure determination, Cu target, Kα radiation, solid state detector, tube voltage 40kV, tube current 40mA.

The raw materials used in the examples and comparative examples: cobalt nitrate [Co(NO ₃ ) ₂ ·6H ₂ O] is analytically pure, ferric nitrate [Fe(NO ₃ ) ₃ ·9H ₂ O] is analytically pure, potassium permanganate [ KMnO ₄ ] is analytically pure, all produced by Sinopharm Chemical Reagent Co., Ltd.; Pseudo-boehmite is an industrial-grade product, the alumina content is 64% by weight, and the pore volume is 0.31 ml/g, produced by Shandong Aluminum Co., Ltd.; Hydrochloric acid, The concentration is 36.5% by weight, analytically pure, produced by Beijing Chemical Plant; carbon monoxide, the concentration is 10% by volume, nitrogen is used as a balance gas, produced by Beijing Helium Pubei Gas Industry Co., Ltd.; catalytic cracking catalyst industrial product (Cat-A, catalyst brand CGP-1), Na ₂ O content 0.24 wt %, RE ₂ O ₃ content 3.2 wt %, Al ₂ O ₃ content 48.0 wt %, average particle size 67 microns, produced by Sinopec Catalyst Co., Ltd.

Example 1

(1) 2.62kg of pseudo-boehmite was added to 14.2kg of deionized water for beating and dispersion, then 238mL of hydrochloric acid was added for acidification 15min to obtain bauxite colloid, the iron nitrate (in Fe ₂ O ₃ in terms of metal oxides, The same below) 100g, cobalt nitrate (in Co ₂ O ₃ , the same below) 100g, KMnO ₄ (in MnO, the same below) 100g were added into 3500mL of water and stirred until fully dissolved, the bauxite colloid was added into it, and after stirring for 20min, The slurry was obtained, and the slurry was spray-dried, and 100 g of the particles obtained by spray-drying (average particle size was 65 μm, and particles with a particle size of 40-80 μm accounted for 60%, the same below) were transferred to a tube furnace and transferred to a tube furnace at a rate of 100 mL/m. A CO/N ₂ mixed gas with a CO concentration of 10% by volume was introduced into the mixture at a flow rate of min, and the mixture was treated at 600° C. for 1.5 h to obtain the composition S-1.

Table 1 shows the measurement results of the content of each component in composition S-1.

The XRD analysis of composition S-1 is carried out, and the XRD spectrum is shown in Figure 1. It can be seen from Figure 1 that the XRD spectrum of composition S-5 without carbon-containing atmosphere treatment has Al ₂ at about 45.3°. O ₃ and Co ₂ AlO ₄ diffraction peaks, while the XRD spectrum of composition S-1 treated with carbon-containing atmosphere not only has diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ around 45.3°, but also 42.6 There are obvious diffraction peaks at ° and 44.9°, and the diffraction peaks at 2θ of 42.6° and 44.9° are the diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-1 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-1 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In the composition S-1 treated with a carbon-containing atmosphere, part of the cobalt oxide was converted into elemental cobalt.

It should be noted that FIG. 1 only lists the XRD patterns in the range of 41°-50°, which are mainly used to illustrate the existence forms of Fe and Co in the composition. Outside the range of 41°-50°, there are other diffraction peaks, such as those of FeO (at 37°, 65° and 59° in 2θ) and CoO (at 37°, 65° and 31° in 2θ) , the diffraction peaks outside the range of 41°-50° have nothing to do with the diffraction peaks of FeC and elemental Co, and the present invention does not further analyze the spectrum.

Example 2

(1) 2.56kg of pseudo-boehmite was added to 13.9kg of deionized water for beating and dispersion, then 232mL of hydrochloric acid was added for acidification for 15min to obtain bauxite colloid, 140g of iron nitrate, 60g of cobalt nitrate, KMnO ₄ (in terms of MnO) 160g was added into 3500mL of water and stirred until fully dissolved, the bauxite colloid was added into it, and after stirring for 20min, a slurry was obtained, the slurry was spray-dried, and 100g of the particles obtained by spray-drying were transferred to a tube furnace, A CO/N ₂ mixed gas with a CO concentration of 10% by volume was introduced at a flow rate of 100 mL/min, and the mixture was treated at 500° C. for 3 h to obtain the composition S-2.

Table 1 shows the measurement results of the content of each component in composition S-2. The XRD analysis results of composition S-2 were similar to those of Example 1. In the XRD spectrum of composition S-2 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ at about 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-2 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-2 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In the composition S-2 treated with a carbon-containing atmosphere, part of the cobalt oxide was converted into elemental cobalt.

Example 3

(1) 2.56kg of pseudo-boehmite was added to 13.9kg of deionized water for beating and dispersion, then 232mL of hydrochloric acid was added for acidification for 15min to obtain bauxite colloid, iron nitrate 100g, cobalt nitrate 200g, KMnO ₄ (in terms of MnO, the same below) 60g was added into 3500mL of water and stirred until fully dissolved, the bauxite colloid was added to it, and after stirring for 20min, a slurry was obtained, the slurry was spray-dried, and 100g of the particles obtained by spray-drying were transferred to a tubular In the furnace, a CO/N ₂ mixed gas with a CO concentration of 10% by volume was introduced into the furnace at a flow rate of 100 mL/min, and the mixture was treated at 650° C. for 1 h to obtain the composition S-3.

The results of the content determination of each component in composition S-3 are listed in Table 1. The XRD analysis results of composition S-3 were similar to those of Example 1. In the XRD spectrum of composition S-3 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ around 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-3 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-3 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In composition S-3 treated with carbon-containing atmosphere, part of the cobalt oxide was converted into elemental cobalt.

Example 4

(1) 2.56kg of pseudo-boehmite was added to 13.9kg of deionized water for beating and dispersion, then 232mL of hydrochloric acid was added for acidification for 15min to obtain bauxite colloid, 200g of iron nitrate, 120g of cobalt nitrate, KMnO ₄ (in terms of MnO) 40g was added into 3500mL of water and stirred until fully dissolved, the bauxite colloid was added to it, and after stirring for 20min, a slurry was obtained, the slurry was spray-dried, and 100g of the particles obtained by spray-drying were transferred to a tube furnace, A CO/N ₂ mixed gas with a CO concentration of 10% by volume was introduced at a flow rate of 100 mL/min, and the mixture was treated at 600° C. for 1.5 h to obtain the composition S-4.

Table 1 shows the measurement results of the content of each component in composition S-4. The XRD analysis results of composition S-4 were similar to those of Example 1. In the XRD spectrum of composition S-4 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ around 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-4 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-4 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In composition S-4 treated with carbon-containing atmosphere, part of the cobalt oxide was converted into elemental cobalt.

Example 5

According to the method of Example 1, the difference is that the CO/N ₂ mixed gas with a CO concentration of 10% by volume is replaced with air to obtain the composition S-5.

The content determination results of each component in composition S-5 are listed in Table 1. XRD analysis of composition S-5 was carried out. It can be seen from the XRD spectrum (as shown in Figure 1) that there are no obvious diffraction peaks at 2θ of 42.6°, 44.2° and 44.9°, which proves that Fe in composition S-5 and Co exist in the form of oxides.

Example 6

According to the method of Example 1, the difference is that the same mass of CeCl ₂ is used to replace KMnO ₄ in terms of metal oxide to obtain the composition S-6.

Table 1 shows the measurement results of the content of each component in composition S-6. The XRD analysis results of composition S-6 were similar to those of Example 1. In the XRD spectrum of composition S-6 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ around 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-6 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-6 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In composition S-6 treated with carbon-containing atmosphere, part of the cobalt oxide was converted to elemental cobalt.

Example 7

According to the method of Example 1, the difference is that the amount of ferric nitrate calculated as metal oxide is 50 g, and the amount of cobalt nitrate is 150 g to obtain composition S-7.

Table 1 shows the results of content determination of each component in composition S-7. The XRD analysis results of composition S-7 were similar to Example 1. In the XRD spectrum of composition S-7 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ around 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-7 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-7 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In composition S-7 treated with carbon-containing atmosphere, part of the cobalt oxide was converted to elemental cobalt.

Example 8

According to the method of Example 1, the difference is that the amount of ferric nitrate calculated as metal oxide is 150 g, and the amount of cobalt nitrate is 50 g to obtain composition S-8.

Table 1 shows the results of determination of the content of each component in composition S-8. The XRD analysis results of composition S-8 were similar to Example 1. In the XRD spectrum of composition S-8 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ at about 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-8 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-8 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In composition S-8 treated with a carbon-containing atmosphere, part of the cobalt oxide was converted to elemental cobalt.

Example 9

According to the method of Example 1, the difference is that the mixed gas of CO/N ₂ with a concentration of 10 vol % is replaced with a mixed gas of ethane/nitrogen with a concentration of 10 vol % of ethane to obtain the composition S-9.

The content determination results of each component in composition S-9 are listed in Table 1. The XRD analysis results of composition S-9 were similar to those of Example 1. In the XRD spectrum of composition S-9 treated with carbon-containing atmosphere, there are not only diffraction peaks of Al ₂ O ₃ and Co ₂ AlO ₄ at about 45.3°, but also obvious diffraction peaks at 42.6° and 44.9°, 2θ The diffraction peaks at 42.6° and 44.9° are diffraction peaks of FeC (Fe ₃ C and Fe ₇ C ₃ ). In composition S-9 treated with a carbon-containing atmosphere, part of the iron oxide was converted to iron carbide. In addition, compared with composition S-5, composition S-9 has a diffraction peak at 44.2°, and the diffraction peak at 2θ of 44.2° is the diffraction peak of elemental cobalt. In composition S-9 treated with carbon-containing atmosphere, part of the cobalt oxide was converted to elemental cobalt.

Comparative Example 1

According to the method of Example 1, the difference is that the same mass of ferric nitrate was used to replace the cobalt nitrate in terms of metal oxide to obtain the composition D-1.

Table 1 shows the results of content determination of each component in composition D-1.

Comparative Example 2

According to the method of Example 1, the difference is that in terms of metal oxide, the same mass of cobalt nitrate is used to replace the iron nitrate to obtain the composition D-2.

Table 1 shows the measurement results of the content of each component in composition D-2.

Comparative Example 3

Comparative compositions were prepared according to the method described in US6800586. Take 34.4 grams of dried γ-alumina microsphere carrier, impregnate the alumina microspheres with a solution of 10.09g cerium nitrate, 2.13g lanthanum nitrate and 18mL water, dry at 120°C and bake at 600°C for 1 hour after dipping After that, it was impregnated with a solution prepared by 2.7 g of copper nitrate and 18 mL of water, dried at 120° C. and calcined at 600° C. for 1 hour to obtain composition D-3. In composition D-3, based on the total amount of composition D-3, in terms of oxides, the content of RE ₂ O ₃ is 12 wt %, and the content of CuO is 2.3 wt % (RE represents a lanthanoid metal element).

Table 1

Note: The content of each component is calculated as oxide, and the unit is % by weight.

Test Example 1

This test example is used for reducing CO and NOx emissions in incompletely regenerated flue gas under aerobic conditions by the compositions provided in the above examples and comparative examples that can reduce CO and NOx emissions.

The composition capable of reducing CO and NOx emissions is uniformly blended with the catalytic cracking catalyst (Cat-A) described above (the composition capable of reducing CO and NOx emissions accounts for 3% of the total amount of the composition capable of reducing CO and NOx emissions and the catalytic cracking catalyst). 2.2 wt%) after aging at 800° C. and 100% steam atmosphere for 12 hours, the catalytic cracking reaction-regeneration evaluation was carried out.

The catalytic cracking reaction-regeneration evaluation was carried out on a small fixed-bed simulated flue gas NOx reduction device, the aged catalyst loading was 10 g, the reaction temperature was 650°C, and the volume flow of feed gas was 1500 mL/min. The feed gas contained 3.7 vol% CO, 0.5 vol% oxygen, 800 ppm _NH3 , and the balance was _N2 . The gas products were analyzed by an on-line infrared analyzer to obtain the concentrations of NH ₃ , NOx and CO after the reaction. The results are listed in Table 2.

Table 2

As can be seen from the data in Table 2, using the composition capable of reducing CO and NOx emissions provided by the present invention is used in the incomplete regeneration process (aerobic condition) of the catalytic cracking process, compared with the combination provided by the comparative example capable of reducing CO and NOx emissions The composition has better CO, _NH3 and NOx emission reduction performance, and the aged composition capable of reducing CO and NOx emission was used in the evaluation process, and the aged composition capable of reducing CO and NOx emission was removed. The activities of CO, NH ₃ and NOx are still relatively high, therefore, the composition capable of reducing CO and NOx emissions provided by the present invention has better hydrothermal stability.

Test Example 2

This test example is used for reducing CO and NOx emissions in incompletely regenerated flue gas under anaerobic conditions by the compositions provided in the above examples and comparative examples that can reduce CO and NOx emissions.

The method of Test Example 1 was followed, except that the raw material gas contained 3.7% by volume of CO, 800 ppm of NH ₃ , and the balance was N ₂ . The concentrations of NH ₃ , NOx and CO after the reaction were obtained, and the results are listed in Table 3.

table 3

Numbering NOx concentration, ppm NH₃ concentration, ppm CO concentration, vol% Example 1 S-1 0 149 3.69 Comparative Example 1 D-1 0 352 3.69 Comparative Example 2 D-2 0 344 3.7 Comparative Example 3 D-3 0 423 3.7 Example 2 S-2 0 134 3.7 Example 3 S-3 0 107 3.67 Example 4 S-4 0 114 3.69 Example 5 S-5 0 159 3.67 Example 6 S-6 0 183 3.67 Example 7 S-7 0 162 3.67 Example 8 S-8 0 165 3.67 Example 9 S-9 0 153 3.68

As can be seen from Table 3, even if the incompletely regenerated flue gas is treated under anaerobic conditions, the composition capable of reducing CO and NOx emission provided by the present invention has better performance than the composition capable of reducing CO and NOx emission provided by the comparative example The performance _of reducing CO and NH ₃ emissions is excellent, and the aged composition that can reduce CO and NOx emissions is used in the evaluation process. Therefore, the composition capable of reducing CO and NOx emissions provided by the present invention has better hydrothermal stability.

From the data in Table 2 and Table 3, it can be seen that the composition capable of reducing CO and NOx emissions provided by the present invention is suitable for incomplete regeneration under aerobic and anaerobic conditions, and has better regeneration flue gas treatment capacity. In particular, it can be seen from the comparison between Example 1 and Example 5 that the preferred roasting of the present invention is carried out in a carbon-containing atmosphere, so that the performance of the composition capable of reducing CO and NOx emissions is further improved; from Example 1 and Example 6 It can be seen from the comparison that the use of the preferred metal elements of the present invention further improves the performance of the composition capable of reducing CO and NOx emissions; The mass ratio of Fe to Co further improves the performance of the composition capable of reducing CO and NOx emissions; from the comparison between Example 1 and Example 9, it can be seen that the preferred carbon-containing atmosphere of the present invention is used for treatment, so that CO and NOx emissions can be reduced The performance of the composition is further improved; from the comparison between Example 1 and Comparative Examples 1-3, it can be seen that by using Fe and Co together, the performance of the composition capable of reducing CO and NOx emissions is greatly improved.

The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the specific details of the above-mentioned 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 each specific technical feature described in the above-mentioned specific implementation manner may be combined in any suitable manner under the circumstance that there is no contradiction. In order to avoid unnecessary repetition, the present invention will not describe various possible combinations.

In addition, the various embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the contents disclosed in the present invention.

Claims (33)

1. A fluid catalytic cracking process, the process comprising: the hydrocarbon oil is contacted with a catalyst for reaction, and then the catalyst after the contact reaction is subjected to incomplete regeneration, wherein the catalyst comprises a catalytic cracking catalyst and a composition capable of reducing CO and NOx emission, and the composition capable of reducing CO and NOx emission can reduce NH₃CO and NO_XDischarging of (3);

the composition capable of reducing CO and NOx emissions comprises: the inorganic oxide carrier and a first metal element and a second metal element loaded on the inorganic oxide carrier, wherein the first metal element is selected from non-noble metal elements in a VIII group, the first metal element comprises Fe and Co, and the weight ratio of Fe to Co is 1: (0.1-10), the second metal element is selected from at least one of Cu, Zn, Ti, Zr, V, Cr, Mo, W, Mn and rare earth elements;

based on the total amount of the composition, the content of the inorganic oxide carrier is 50-90 wt%, and the content of the first metal element is 3-30 wt% and the content of the second metal element is 1-20 wt% in terms of oxide.

2. The method according to claim 1, wherein the inorganic oxide support is contained in an amount of 60 to 90 wt%, the first metal element is contained in an amount of 5 to 25 wt%, and the second metal element is contained in an amount of 2 to 15 wt%, in terms of oxide, based on the total amount of the composition.

3. The method according to claim 2, wherein the inorganic oxide support is present in an amount of 76 to 86 wt%, based on the total amount of the composition, the first metal element is present in an amount of 10 to 16 wt%, and the second metal element is present in an amount of 2 to 8 wt%, calculated as an oxide.

4. The method of claim 1, wherein the second metal element is selected from at least one of Zr, V, W, Mn, Ce, and L a.

5. The method according to claim 4, wherein the second metal element is Mn.

6. The method of claim 1, wherein the weight ratio of Fe to Co, calculated as oxides, is 1: (0.3-3).

7. The method of claim 6, wherein the weight ratio of Fe to Co, calculated as oxides, is 1: (0.5-2).

8. The method of any one of claims 1-7, wherein the Fe in the composition is at least partially present in the form of iron carbide; the Co in the composition is at least partially present in the form of elemental cobalt.

9. The method of claim 8, wherein the composition has an XRD pattern with diffraction peaks at 42.6 °, 44.2 ° and 44.9 ° 2 θ.

10. The process of any one of claims 1-7, wherein the inorganic oxide support is selected from at least one of alumina, silica-alumina, zeolite, spinel, kaolin, diatomaceous earth, perlite, and perovskite.

11. The method of claim 10, wherein the inorganic oxide support is selected from at least one of alumina, spinel, and perovskite.

12. The method of claim 11, wherein the inorganic oxide support is alumina.

13. A fluid catalytic cracking process, the process comprising: the hydrocarbon oil is contacted with a catalyst for reaction, and then the catalyst after the contact reaction is subjected to incomplete regeneration, wherein the catalyst comprises a catalytic cracking catalyst and a composition capable of reducing CO and NOx emission, and the composition capable of reducing CO and NOx emission can reduce NH₃CO and NO_XDischarging of (3);

the preparation method of the composition capable of reducing CO and NOx emission comprises the following steps:

mixing and pulping a precursor of an inorganic oxide carrier, a first metal element precursor, a second metal element precursor and water to obtain slurry, carrying out spray drying on the slurry, and then roasting;

wherein the first metal element is selected from non-noble metal elements in group VIII, and the first metal element comprises Fe and Co; the second metal element is at least one selected from Cu, Zn, Ti, Zr, V, Cr, Mo, W, Mn and rare earth elements;

in the first metal element precursor, the dosage of the precursor of Fe and the precursor of Co is such that the weight ratio of Fe to Co in the prepared composition is 1: (0.1-10);

the precursors of the inorganic oxide carrier, the first metal element precursor and the second metal element precursor are used in such amounts that the content of the inorganic oxide carrier is 50 to 90 wt%, the content of the first metal element is 3 to 30 wt% and the content of the second metal element is 1 to 20 wt% in terms of oxide, based on the total amount of the composition, in the prepared composition.

14. The method of claim 13, wherein the firing conditions include: under the atmosphere containing carbon, the temperature is 400-1000 ℃, and the time is 0.1-10 h.

15. The method of claim 14, wherein the firing conditions include: the temperature is 450-650 ℃, and the time is 1-3 h.

16. The method of claim 13, wherein the second metal element is selected from at least one of Zr, V, W, Mn, Ce, and L a.

17. The method of claim 16, wherein the second metallic element is Mn.

18. The method of claim 14, wherein the carbon-containing atmosphere is provided by an elemental carbon-containing gas selected from at least one of CO, methane, and ethane.

19. The method of claim 18, wherein the elemental carbon-containing gas is CO.

20. The method of claim 19, wherein the carbon-containing atmosphere has a concentration of CO in the range of 1-20% by volume.

21. The method of claim 20, wherein the carbon-containing atmosphere has a concentration of CO of 4-10% by volume.

22. The method according to claim 13, wherein the inorganic oxide support is contained in an amount of 60 to 90 wt%, the first metal element is contained in an amount of 5 to 25 wt%, and the second metal element is contained in an amount of 2 to 15 wt%, in terms of oxide.

23. The method of claim 22, wherein the inorganic oxide support is present in an amount of 76 to 86 wt%, and the first metallic element is present in an amount of 10 to 16 wt% and the second metallic element is present in an amount of 2 to 8 wt%, calculated as oxide.

24. The method of any one of claims 13-23, wherein the Fe and Co precursors are used in amounts such that the resulting composition has a weight ratio of Fe to Co, calculated as oxides, of 1: (0.3-3).

25. The method of claim 24, wherein the Fe and Co precursors are used in amounts such that the resulting composition has a weight ratio of Fe to Co, calculated as oxides, of 1: (0.5-2).

26. The method of any one of claims 13-23, wherein the inorganic oxide support is selected from at least one of alumina, silica-alumina, zeolite, spinel, kaolin, diatomaceous earth, perlite, and perovskite.

27. The method of claim 26, wherein the inorganic oxide support is selected from at least one of alumina, spinel, and perovskite.

28. The method of claim 27, wherein the inorganic oxide support is alumina.

29. The method of claim 28, wherein the precursor of alumina is subjected to an acidified peptization treatment prior to pulping.

30. The method of claim 29, wherein the acid used in the acidification peptization process is hydrochloric acid, and the conditions of the acidification peptization process comprise: the acid-aluminum ratio is 0.12-0.22: 1, the time is 20-40 min.

31. The method of any one of claims 13-23, wherein the first and second metallic element precursors are selected from water soluble salts of first and second metallic elements, respectively.

32. The fluid catalytic cracking process of claim 1 or 13, wherein the composition capable of reducing CO and NOx emissions is present in an amount of 0.05 to 5 wt.%, based on the total amount of catalyst.

33. The fluid catalytic cracking process of claim 32, wherein the composition capable of reducing CO and NOx emissions is present in an amount of 0.1 to 3 wt.%, based on the total amount of catalyst.

Images