CN102476975A - A kind of method that magnesium and aluminum modified titanium silicon molecular sieve catalyzes oxidation cycloketone - Google Patents

Abstract

A method for catalyzing and oxidizing cyclic ketone by using a magnesium and aluminum modified titanium-silicon molecular sieve is characterized in that cyclic ketone, a solvent and hydrogen peroxide are reacted in the presence of a catalyst under the conditions that the molar ratio of the cyclic ketone to the solvent to the hydrogen peroxide is 1 to (0-80) to (0.2-20), the temperature is 5-200 ℃, and the reaction pressure is 0.1-3.0 MPa, and a product is recovered, wherein the mass ratio of the catalyst to the cyclic ketone is 1 to (5-300), the catalyst is obtained by modifying the titanium-silicon molecular sieve by using magnesium and aluminum, the mass ratio of magnesium to the titanium-silicon molecular sieve is x, the mass ratio of the magnesium to the titanium-silicon molecular sieve is 0.001-0.99, and the aluminum is Al₂O₃The mass ratio of the titanium-silicon molecular sieve to the titanium-silicon molecular sieve is y, and y is 0.001-0.99.

Description

A kind of method that magnesium and aluminum modified titanium silicon molecular sieve catalyzes oxidation cycloketone

technical field

The invention relates to a method for catalytic oxidation of cyclic ketones, and more particularly relates to a method for oxidizing cyclic ketones with hydrogen peroxide.

Background technique

ε-caprolactone has the advantages of low viscosity, easy processing, and low VOC content. It is used as oligomer and denaturant in the process, which can improve the toughness, low temperature characteristics and reactivity and other functionalities; in terms of coatings, it is used as an improvement in solvents and latex coatings for automotive primers, surface coatings and various building materials. It can improve the toughness of the coating film, improve the low-temperature characteristics, reactivity, and increase the crosslinking density; in terms of adhesives, it can be used to improve the bonding properties of hot-melt adhesives and solvent-based adhesives; in resin modification On the one hand, it can be used to improve softness, fluidity, low temperature impact resistance, formability, etc. In addition, as an important raw material for the production of degradable plastics, it has good biocompatibility, non-toxicity, biodegradability and good drug penetration properties, so it is widely used in biomedical engineering, disposable degradable plastic tableware , film materials, high value-added packaging materials have been widely used. With the enhancement of people's awareness of environmental protection, ε-caprolactone will receive wider attention at home and abroad, and has a broader market prospect.

Worldwide, due to the problems of production safety and product stability in the synthesis of ε-caprolactone, ε-caprolactone is mainly produced by BASF Company located in the United States, Daicel Co., Ltd. in Japan and the United Kingdom. Solvay (Solvay) is produced by the three caprolactone manufacturers.

ε-caprolactone was successfully synthesized in the laboratory as early as the 1930s. The synthesis methods of ε-caprolactone mainly include the Baeyer-Villiger oxidation method, the catalytic dehydrogenation method of 1,6-hexanediol and the intramolecular condensation method of 6-hydroxycaproic acid. Considering the raw materials, equipment and reaction conditions, the Baeyer-Villiger oxidation method is the most effective method.

At present, the industrialized production of ε-caprolactone mainly adopts the Baeyer-Villiger oxidation process of cyclohexanone and peroxycarboxylic acid, but peroxyacid oxidants also have relatively large disadvantages: (1) after the reaction, a large amount of Organic carboxylic acid (salt) waste has a greater impact on the environment, and it is more difficult to recycle or process; (2) the separation and purification of reaction products are more difficult, the selectivity is low, the atom economy is poor, and it does not meet the basic principles of green chemistry; ( 3) Organic peroxyacids need to use high-concentration hydrogen peroxide in the production process, which is unstable in nature, high in production costs, and dangerous in transportation, storage and operation, thus limiting its application in industrial production .

Compared with peroxyacids, H ₂ O ₂ has the broadest application prospect, because it is easy for large-scale industrial application and environmentally friendly, which is in line with the development trend of green chemistry. Bhaumik et al. (Bhaumik, P.Kumar and R.Kumar, Catal.Lett.40 (1996), pp.4750.) studied the Baeyer-Villiger oxidation three-phase reaction system (ketone +H ₂ O ₂ /H ₂ O+catalyst), and the influence of whether acetocyanide was used as solvent was investigated. Bhaumik et al. found that if a small amount of H ₂ SO ₄ was added to the three-phase reaction system, a higher conversion rate would be obtained.

Corma et al. (Corma, LTNemeth, M.Renz, et al.Nature 412(2001), pp.421-423) reported the oxidation of cyclohexanone with 35% H ₂ O ₂ aqueous solution at 56°C with Sn-β molecular sieve catalyst The corresponding lactone is obtained, the selectivity of the lactone is very high, and the catalyst can be reused, and the catalytic activity is not significantly reduced after four reaction cycles.

A method for preparing ε-caprolactone by catalytic oxidation of cyclohexanone is disclosed in CN101307045A. In the method, the catalyst is 50-100% by weight of zinc oxide and 0-50% of other metal oxides The mixture, the solvent is nitrile, the oxidizing agent is hydrogen peroxide or peracetic acid. The method can obtain higher yield and selectivity of caprolactone, and the catalyst is cheap and easy to obtain, simple to prepare, does not contain halogen elements, has high stability and can be repeatedly used.

CN101186601A discloses that a certain amount of nano-flaky magnesium-based compound is used as a catalyst, and a certain proportion of benzonitrile and 1,4-dioxane mixture is used as a solvent to catalyze the oxidation of cyclic ketones to synthesize lactones at a specific reaction temperature compound method. The method can make the total yield of the lactone compound up to 90% under relatively mild conditions. Because the method adopts hydrogen peroxide aqueous solution as an oxidizing agent, the environmental protection problems caused by traditional oxidation methods such as peroxyacid are abandoned. However, metal oxide catalysts have inherent defects in such reactions, such as low catalytic efficiency and small reaction conversion frequency (TON), which are difficult to solve and cannot be industrialized.

Hydroxy acids are important chemical raw materials. Taking 6-hydroxycaproic acid as an example, it has a wide range of applications in the fields of organic synthesis and polymer materials, for example, the preparation of 6-formylcaproic acid, ε-caprolactone, adipic acid, etc., and its derivatives 6-hydroxy Ethyl hexanoate, etc. are commonly used organic chemical intermediates. USP2008306153 introduces a process of oxidation of 6-hydroxycaproic acid to 6 _- formylcaproic acid in _CH2Cl2 solvent with PCC (Pyridinium Chlorochromate) as an oxidizing agent at 37°C.

At present, in the world, cyclohexanone, caprolactone and adipic acid are mainly used as raw materials to prepare 6-hydroxycaproic acid. Among them, cyclohexanone has attracted people's attention due to its relatively low price and wide range of raw material sources. LENARDA Maurizio et al. (Inorganica Chimica Acta, 349, 195-202; 2003) used HBEA molecular sieve Hβ as a catalyst to obtain 6-hydroxyhexanoic acid through the oxidation reaction of cyclohexanone. Literature (Polish Journal of Chemistry, 78(5), 687-697; 2004) reported the reaction of hydrogen peroxide oxidation of cyclohexanone to 6-hydroxyhexanoic acid under the action of several catalysts, using water and n-butanol as solvents. Literature (Angewandte Chemie, International Edition, 41(23), 4481-4484; 2002) introduced that in water and (CF ₃ ) ₂ CHOH solution, using p-MeC ₆ H ₄ SO ₃ H as catalyst, at 55°C Cyclohexanone is oxidized to 6-hydroxycaproic acid by hydrogen peroxide. However, the catalyst used is a homogeneous catalyst, which has the disadvantages of being difficult to separate and endangering the environment, so it cannot be put into industrial production.

Literature (Organic & Biomolecular Chemistry, 7(4), 725-732; 2009) reported a method for preparing 6-hydroxycaproic acid from caprolactone, the first step is in 0 ℃ water and dioxane solvent, Caprolactone was first reacted with NaOH for 2.5 hours, then warmed to room temperature and reacted with HCl to give 6-hydroxycaproic acid. The literature (Journal of the American Chemical Society, 130(5), 1718-1726; 2008) also introduced a process of preparing 6-hydroxycaproic acid by reacting cyclohexanone with strong base (NaOH) and strong acid (HCl) . The literature (Applied and Environmental Microbiology, 65(5), 2232-2234; 1999) describes a reaction in which an enzyme catalyzes the hydrolysis of caprolactone to 6-hydroxycaproic acid in a near-neutral water environment at 30°C. Since strong acid and strong alkali are used as reactants in the above-mentioned various methods, the equipment is severely corroded, a large amount of waste is generated, and the environment is affected, so it does not conform to the principles of green and sustainable development chemistry.

CN1211969A discloses a kind of preparation 1,6-hexanediol and 6- A process for hydroxycaproic acid or its esters, wherein the bottom product obtained after distilling the hydrogenated product to remove hexanediol and hydroxycaproic acid or its ester is recycled to the hydrogenation step, the bottom product mainly containing 6-hydroxycaproic acid Oligoesters; reacting a mixture of starting materials and recycle streams at 100-300° C. and 10-300 bar in the liquid phase over said hydrogenation catalyst, in the reactor the carboxyl groups to be hydrogenated with hydrogen The molar ratio is 1:5-1:100.

Dicarboxylic acids are also important organic chemical raw materials. Taking adipic acid as an example, it is an industrially important dicarboxylic acid. Together to produce nylon 66 (polyamide) and engineering plastics. In addition, it is also used in the production of various ester products, as plasticizers and advanced lubricants, as raw materials for polyurethane elastomers, in the production of unsaturated polyesters, hexanediol and adipate, and in various foods And beverage acidulant, medicine, yeast purifying agent, insecticide, adhesive, raw material for synthetic leather, synthetic dye and fragrance, etc.

In 1937, the DuPont Company of the United States oxidized cyclohexanol with nitric acid, and first realized the industrial production of adipic acid. In the 1960s, the industry gradually switched to the cyclohexane oxidation method, that is, the intermediate product cyclohexanone and cyclohexanol mixture (that is, ketone alcohol oil, also known as KA oil) was first prepared from cyclohexane, and then the KA oil was decomposed. Nitric acid or air oxidation. The nitric acid oxidation KA oil method generally uses an excess of nitric acid with a concentration of 50% to 60%, and is carried out in series through two-stage reactors. The catalyst used in the reaction is copper-vanadium system (copper 0.1%-0.5%, vanadium 0.1%-0.2%), the temperature is 60-80°C, and the pressure is 0.1-0.4MPa. The yield is 92%-96% of the theoretical value. After nitric acid is distilled from KA oil oxidation products, high-purity adipic acid can be obtained through two-stage crystallization and refining. Raw material consumption quota: cyclohexanol (or KA oil) 740kg/t, nitric acid (100%) 908kg/t, copper 0.2kg/t, vanadium (calculated as V ₂ O ₅ ) 0.1kg/t. However, this reaction has strong corrosion problems on equipment, serious environmental pollution, complex process, high energy consumption, and does not conform to the principles of green chemistry.

The air oxidation method uses copper acetate and manganese acetate as catalysts and acetic acid as solvent to directly oxidize KA oil with air. Generally, two-stage reactors are connected in series: the first-stage reaction temperature is 160-175°C, the pressure is 0.7MPa (gauge pressure), and the reaction time is about 3h; the second-stage reaction temperature is 80°C, the pressure is 0.7MPa (gauge pressure), and the reaction time is about 3h. The oxidation product is purified by two-stage crystallization, and the recovered solvent can be recycled after treatment. The reaction time of this method is long, the reaction efficiency is low, and the product separation is difficult, so it is still rarely used.

Japanese scientist Noyori Ryoji et al. have developed a heteropoly acid Na ₂ WO ₄ 2H ₂ O as a catalyst, [CH ₃ N(nC ₈ H ₁₇ ) ₃ ]HSO ₄ as a phase transfer catalyst, and hydrogen peroxide to directly oxidize cyclohexene to prepare adipic acid. The reactant ratio is cyclohexene:Na ₂ WO ₄ 2H ₂ O:[CH ₃ N(nC ₈ H ₁₇ ) ₃ ]HSO ₄ =100:1:1, 30% H ₂ O ₂ is the oxidizing agent, at 75- After reacting at 90°C for 8 hours, the yield of adipic acid reached 93%. However, heteropolyacid catalysts have disadvantages such as unstable properties, small specific surface area, easy deactivation, difficult recovery and short service life, so they have not been widely promoted at present.

Other production methods of adipic acid include the chlorocyclohexane method, which is to recover adipic acid from the oxidation by-product of cyclohexane, and to prepare adipic acid from acrylate. Asahi Kasei Corporation of Japan has also carried out the research on the one-step air oxidation of cyclohexane to adipic acid. Chinese patent CN101337879 discloses a catalyst monometalloporphyrin or μ-oxygen double metalloporphyrin or a mixed catalyst composed of transition metal salts or oxides, which is dissolved in cyclohexane at 1-500ppm, to catalyze the air oxidation of cyclohexane Process and equipment for preparing adipic acid from alkanes.

Contents of the invention

The object of the present invention is to provide a method for catalytically oxidizing cyclic ketones to prepare corresponding lactones, hydroxyacids and dicarboxylic acids.

The method for catalytic oxidation of cyclic ketone provided by the invention is characterized in that according to the molar ratio of cyclic ketone: solvent: hydrogen peroxide=1: (0～80): (0.2～20), the temperature is 5～200° C., and the reaction pressure is Under the condition of 0.1～3.0MPa, react in the presence of a catalyst and recover the product, the mass ratio of catalyst to cyclic ketone is 1: (5～300), and the catalyst is made of magnesium and aluminum on titanium silicon molecular sieve The modification results in that the mass ratio of magnesium to titanium-silicon molecular sieve in terms of MgO is x, and x=0.001-0.99, and the mass ratio of aluminum in terms of Al ₂ O ₃ to titanium-silicon molecular sieve is y, and y=0.001-0.99.

In the method provided by the present invention, the cyclic ketone can be selected from various monocyclic ketones, polycyclic ketones and cyclic ketones with side chain R, wherein R is preferably an alkyl functional group with 1-6 carbons. In a preferred embodiment of the invention, the production of said lactone is especially suitable for catalytic oxidation reactions starting from cyclohexanone, cyclopentanone or methylcyclohexanone.

In the method provided by the present invention, said catalyst can be obtained by modifying titanium-silicon molecular sieve by magnesium and aluminum through solid-state ion migration method, the mass ratio of magnesium to titanium-silicon molecular sieve in terms of MgO is x, x=0.001～0.99, The mass ratio of aluminum to titanium silicon molecular sieve is y in terms of _Al2O3 , y=0.001～ _0.99 , said x is preferably 0.005～0.50, more preferably 0.005～0.15, said y is preferably 0.005～0.50, more preferably 0.005 ~0.15, and the ratio of x and y is preferably between 0.1~5, more preferably 0.5~2. Said titanium-silicon molecular sieve is selected from one or more mixtures of TS-1, TS-2, Ti-BETA and Ti-MCM-22, the preferred titanium-silicon molecular sieve is TS-1, more preferably a The TS-1 titanium silicon molecular sieve of a kind of hollow grain (referring to CN1301599A), the radial length of the cavity part of its hollow grain is 2～300 nanometers, at 25 ℃, P/P ₀ =0.10 and adsorption time 1 hour The measured benzene adsorption amount under the conditions is at least 50 mg/g, and there is a hysteresis loop between the adsorption isotherm and the desorption isotherm of low-temperature nitrogen adsorption.

Said magnesium and aluminum carry out the method that titanium-silicon molecular sieve is modified by solid-state ion migration method and include according to titanium-silicon molecular sieve: crystalline acidic metal aluminum salt: crystalline basic metal magnesium salt=100: (0.01～100): (0.01～ 100), preferably 100:(0.1～90):(0.1～90) ratio, adding titanium silicon molecular sieve, crystalline acidic metal aluminum salt and crystalline basic metal magnesium salt into a mortar, grinding and mixing, and then transferring to a crucible , process and recover the product under roasting conditions, wherein, the titanium silicon molecular sieve is calculated in grams, the crystalline acidic metal aluminum salt is calculated in Al ₂ O ₃ grams, the crystalline basic metal magnesium salt is calculated in MgO in grams, and the crystalline acidic metal salt selected from soluble aluminum salts, such as one or more of AlCl ₃ , Al ₂ (SO ₄ ) ₃ and Al(NO ₃ ) ₃ , and said crystalline alkali metal salts are selected from soluble magnesium salts, such as MgCl ₂ , One or more of MgSO ₄ and Al(NO ₃ ) ₂ .

In the method provided by the invention, said catalyst can also be prepared through the following process: according to titanium silicon molecular sieve: crystalline acidic metal aluminum salt: crystalline basic metal magnesium salt=100: (0.0001～100): (0.0001～100) The ratio of titanium silicon molecular sieve, crystalline acidic metal aluminum salt and crystalline basic metal magnesium salt is mixed with water and evenly impregnated, then dried and roasted to recover the product.

In the method provided by the present invention, hydrogen peroxide is used as the oxidant, because the reduction product is only water and is environmentally friendly, and it is a green oxidant, while high-concentration hydrogen peroxide has potential safety hazards during production, storage, transportation and use due to its unstable properties. And the cost is higher. It is usually added to the reaction system in the form of aqueous hydrogen peroxide solution with a concentration of 10-60% by mass. For example, industrial-grade aqueous hydrogen peroxide has 27.5%, 30% and 35%, and the mass fraction is usually 30%. of hydrogen peroxide. In the proportioning of raw materials, said hydrogen peroxide is calculated as hydrogen peroxide.

In the method provided by the present invention, the suitable reaction temperature is 5-200°C, both of which can effectively carry out the catalytic oxidation reaction. However, for different reaction temperatures, we found that the distribution trends of the generated reaction products are not the same. For example, when reacting at a lower temperature range below 75°C, preferably 20-75°C, it is beneficial to the high selectivity of lactones, while The selectivity of hydroxy acids and dicarboxylic acids is relatively low; further increase the reaction temperature to the reaction temperature range of 100 ° C, preferably 80 ~ 95 ° C, the selectivity of hydroxy acids will gradually increase, and its selectivity is higher than that of internal Selectivity for esters and dicarboxylic acids. And in the higher temperature range of 100-200°C, preferably 100-160°C, we found that the increase in temperature is more favorable for the formation of dicarboxylic acids.

In the method provided by the present invention, the influence of the change of the reaction pressure on the reaction product is not obvious. Considering the economical efficiency of the operation, the reaction pressure is preferably 0.1-0.5 MPa.

In the method provided by this method, inert organic matter and/or water are selected as the solvent. The inert organic compound is a compound with a boiling point close to that of the reactant or a compound with a high polarity and a high dielectric constant. Among them, said compound with a boiling point close to the reactant can be a lower aliphatic alcohol, ketone, acid, ester, usually an alcohol, ketone, acid, ester, etc. with 1 to 6 carbon numbers, such as methanol, ethanol, tert-butyl Alcohol, acetone, acetic acid, propionic acid, ethyl acetate or dioxane, etc.; said inert organic solvents with high polarity and high dielectric constant, such as acetonitrile, chloroform, sulfolane, etc.

The inventor unexpectedly found that when using acetone or dioxane as a solvent, especially cyclic ketone: the molar ratio of hydrogen peroxide is 1: (0.2～10) and the mass ratio of catalyst to cyclic ketone is 1: 5～100 , the molar ratio with cyclic ketone is (0.2～10):1, when the temperature is 20～75°C and the pressure is 0.1～0.5MPa, compared with other organic solvents such as acetonitrile, methanol, etc., the corresponding The selectivity of lactones is increased by at least 20%; and when ethanol or ethyl acetate is used as a solvent, when the temperature is increased to 80-95°C, the reaction time is between 3 and 6 hours, and the selectivity of the corresponding hydroxy acids also increases. Compared with the use of other solvents, it is greatly improved; when acetic acid or propionic acid is used as the solvent, the temperature is raised above 100 ° C, and the reaction time exceeds 5 hours when the molar ratio of hydrogen peroxide to ketone is higher than 5 , the selectivity of the corresponding dicarboxylic acid is significantly improved compared with other solvents. Therefore, the method provided by the present invention can flexibly control operating parameters such as molar ratio of reactants, temperature and solvent type according to different target products. For example, when the target product is a lactone, it is preferable to use dioxane and/or acetone as the reaction solvent at a temperature of 20-75°C; when the target product is a hydroxy acid, it is preferably at a temperature of 80-95°C , using ethanol and/or ethyl acetate as the reaction solvent; when the target product is a dibasic carboxylic acid, the reaction temperature can be increased, preferably at a temperature of 100-160° C., using acetic acid and/or propionic acid as the reaction solvent.

The method for the catalytic oxidation of cyclic ketones provided by the present invention can adopt batch operation or continuous operation mode. For example, when the batch method is used, after the cyclic ketone, solvent, and catalyst are loaded into the reactor, hydrogen peroxide is added once or continuously; when the continuous method is used, a fixed bed or slurry bed reactor is used to beat the catalyst and solvent. Continuously add cyclic ketone and hydrogen peroxide while continuously separating products. The method provided by the invention can also adopt a closed tank reaction, that is, the catalyst, solvent, ketone, and hydrogen peroxide are added at the same time and then reacted.

In the method provided by the invention, the process of recovering the product is conventional separation methods such as distillation, crystallization and extraction that are familiar to people. Specifically, first use relatively high temperature conditions to crystallize and separate easily separated dibasic carboxylic acids, and then use relatively lower conditions to crystallize and separate monobasic hydroxycarboxylic acids. The raw materials, lactones and other by-products are obtained by means of distillation or extraction. separate.

The method for catalytically oxidizing cyclic ketones provided by the present invention uses the acid-base bifunctional titanium-silicon molecular sieve modified by magnesium and aluminum as a catalyst. Since the acid-base center is introduced in the molecular sieve, it can be effectively compared with the catalytic oxidation performance of the titanium-silicon molecular sieve. Synergistically, it improves the reaction activity and activity stability for specific catalytic oxidation reactions, so that its catalytic oxidation activity and catalytic activity stability are also better under the oxidation of hydrogen peroxide under the condition of high selectivity. The method provided by the invention can flexibly control operating parameters such as the molar ratio of reactants, temperature and solvent type, and can obtain different target products.

Detailed ways

The present invention will be further described below by embodiment, but content of the present invention is not limited thereby.

In each of the following examples, all reagents used are commercially available chemically pure reagents.

The concentration of each substance after the reaction in Comparative Examples and Examples was quantitatively analyzed by gas chromatography. The 6890 type gas chromatograph produced by Agilent Company used; the analytical chromatographic column used is FFAP column.

In the embodiment, the conversion ratio of cyclic ketones, the selectivity of lactones, hydroxyacids and dicarboxylic acids are respectively calculated according to the following formula:

Example 1

Catalyst preparation process: get 10 grams of titanium-silicon molecular sieves with hollow grains (produced by Hunan Jianchang Petrochemical Company, brand HTS, which is MFI structure through X-ray diffraction analysis, the adsorption isotherm and desorption isotherm of the low-temperature nitrogen adsorption of this molecular sieve There is a hysteresis ring between them, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the molecular sieve sample is measured under the conditions of 25 °C, P/P ₀ =0.10, and adsorption time of 1 hour Benzene adsorption capacity is 78 mg/gram), 12.75 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 7.02 grams of magnesium chloride hexahydrate MgCl ₂ 6H ₂ O were added to the mortar and ground and mixed evenly, and then transferred to The crucible was transferred to a muffle furnace for calcination at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -HTS (x=0.014, y=0.017).

The process of catalyzing the oxidation of cyclic ketones: Weigh 2.3 grams of the above magnesium and aluminum modified titanium silicon molecular sieve xMgO-yAl ₂ O ₃ -HTS (x=0.014, y=0.017) catalyst and put it in a 100ml three-necked flask, and then add Magnetic stirring bar, 9.81 grams of cyclohexanone, 3.6 grams of water, 20 grams of acetic acid, 6.4 grams of methanol and 46 ml of 30% hydrogen peroxide, the molar ratio of cyclohexanone to hydrogen peroxide is 1:4. The three-necked flask is placed on a temperature-controlled magnetic stirrer, and the upper part of the three-necked flask is condensed and refluxed with a condenser, and the magnetic stirrer and heating device are started to start the reaction. The reaction temperature was controlled at about 105°C. After 6 hours of reaction, the conversion rate of cyclohexanone was 89.35%, the selectivity of generating ε-caprolactone was 4.75%, the selectivity of 6-hydroxycaproic acid was 13.89%, and the Acid selectivity was 78.67%.

Example 2

Catalyst preparation process: get 10 grams of titanium-silicon molecular sieves with hollow grains (produced by Hunan Jianchang Petrochemical Company, brand HTS, which is MFI structure through X-ray diffraction analysis, the adsorption isotherm and desorption isotherm of the low-temperature nitrogen adsorption of this molecular sieve There is a hysteresis ring between them, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the molecular sieve sample is measured under the conditions of 25 °C, P/P ₀ =0.10, and adsorption time of 1 hour Benzene adsorption capacity is 78 mg/g), 14.87 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 11 grams of magnesium chloride hexahydrate MgCl ₂ 6H ₂ O were added to the mortar, ground and mixed, and then transferred to The crucible was transferred into a muffle furnace for calcination at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -HTS (x=0.022, y=0.019).

The process of catalytic oxidation of cyclic ketones: Weigh 2.44 grams of magnesium and aluminum modified titanium silicon molecular sieve xMgO-yAl ₂ O ₃ -HTS (x=0.022, y=0.019) into a 100ml three-necked flask, and then add magnetic stirring Son, 9.81 gram cyclohexanone, 24 gram propionic acid and 46ml concentration are 30% hydrogen peroxide, and the mol ratio of cyclohexanone and hydrogen peroxide is now 1: 4. The three-necked flask is placed on a temperature-controlled magnetic stirrer, and the upper part of the three-necked flask is condensed and refluxed with a condenser, and the magnetic stirrer and heating device are started to start the reaction. The reaction temperature was controlled at about 110°C. After 12 hours of reaction, the conversion rate of cyclohexanone was 99.27%, the selectivity of ε-caprolactone was 0.01%, the selectivity of 6-hydroxycaproic acid was 0.21%, and the selectivity of adipic acid The selectivity is 98.10%.

Example 3

Catalyst preparation process: get 10 grams of titanium-silicon molecular sieves with hollow grains (produced by Hunan Jianchang Petrochemical Company, brand HTS, which is MFI structure through X-ray diffraction analysis, the adsorption isotherm and desorption isotherm of the low-temperature nitrogen adsorption of this molecular sieve There is a hysteresis ring between them, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the molecular sieve sample is measured under the conditions of 25 °C, P/P ₀ =0.10, and adsorption time of 1 hour The amount of benzene adsorption is 78 mg/g), 12 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 16 grams of magnesium chloride hexahydrate MgCl ₂ 6H ₂ O were added to the mortar, ground and mixed, and then transferred to The crucible was transferred to a muffle furnace for calcination at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -HTS (x=0.031, y=0.016).

The process of catalytic oxidation of cyclic ketones: Weigh 2.65 grams of magnesium and aluminum modified titanium silicon molecular sieve xMgO-yAl ₂ O ₃ -HTS (x=0.031, y=0.016) into a 100ml three-necked flask, and then add magnetic stirring Son, 19.63 gram cyclohexanone, 28 gram ethanol and 46ml concentration are 30% hydrogen peroxide, now the mol ratio of cyclohexanone and hydrogen peroxide is 1:2. The three-necked flask is placed on a temperature-controlled magnetic stirrer, and the upper part of the three-necked flask is condensed and refluxed with a condenser, and the magnetic stirrer and heating device are started to start the reaction. The reaction temperature was controlled at about 84°C. After 6 hours of reaction, the conversion rate of cyclohexanone was 73.25%, the selectivity of ε-caprolactone was 2.61%, the selectivity of 6-hydroxycaproic acid was 86.97%, and the selectivity of adipic acid The selectivity is 10.08%.

Example 4

Catalyst preparation process: get 10 grams of titanium-silicon molecular sieves with hollow grains (produced by Hunan Jianchang Petrochemical Company, brand HTS, which is MFI structure through X-ray diffraction analysis, the adsorption isotherm and desorption isotherm of the low-temperature nitrogen adsorption of this molecular sieve There is a hysteresis ring between them, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the molecular sieve sample is measured under the conditions of 25 °C, P/P ₀ =0.10, and adsorption time of 1 hour Benzene adsorption capacity is 78 mg/g), 20 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 17 grams of magnesium chloride hexahydrate MgCl ₂ 6H ₂ O were added to the mortar, ground and mixed, and then transferred to The crucible was transferred to a muffle furnace for calcination at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -HTS (x=0.034, y=0.026).

The process of catalytic oxidation of cyclic ketones: Weigh 7.98 grams of titanium-silicon molecular sieves xMgO-yAl ₂ O ₃ -HTS (x=0.034, y=0.026) modified by magnesium and aluminum, and put them in a 100 ml closed reactor with a pressure gauge, and then A magnetic stirring bar, 19.63 g of cyclopentanone, 5.4 g of acetone, 14 g of ethyl acetate and 46 ml of 30% hydrogen peroxide were added in sequence, and the molar ratio of cyclopentanone to hydrogen peroxide was 1:2. Put the closed reactor on a temperature-controlled magnetic stirrer with an oil bath, start the magnetic stirrer and heating device, and start the reaction. The reaction temperature is controlled at about 83°C. After 7.5 hours of reaction, the self-generated pressure is 1.6MPa. The conversion rate of cyclopentanone was 92.31%, the selectivity of δ-valerolactone was 3.92%, the selectivity of 5-hydroxyvaleric acid was 89.26%, and the selectivity of glutaric acid was 5.61%.

Example 5

Catalyst preparation process: get 10 grams of titanium-silicon molecular sieves with hollow grains (produced by Hunan Jianchang Petrochemical Company, brand HTS, which is MFI structure through X-ray diffraction analysis, the adsorption isotherm and desorption isotherm of the low-temperature nitrogen adsorption of this molecular sieve There is a hysteresis ring between them, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the molecular sieve sample is measured under the conditions of 25 °C, P/P ₀ =0.10, and adsorption time of 1 hour Benzene adsorption capacity is 78 mg/g), 8.2 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 7.1 grams of magnesium chloride hexahydrate MgCl ₂ 6H ₂ O were added to the mortar and ground for mixing and then transferred to The crucible was transferred to a muffle furnace for calcination at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -HTS (x=0.011, y=0.014).

The process of catalytic oxidation of cyclic ketones: Weigh 3.31 grams of magnesium and aluminum modified titanium silicon molecular sieve xMgO-yAl ₂ O ₃ -HTS (x=0.011, y=0.014) into a 100ml three-necked flask, and then add magnetic stirring Son, 19.63 gram cyclopentanone, 23 gram dioxane and 23ml concentration are 30% hydrogen peroxide, and now the mol ratio of cyclopentanone and hydrogen peroxide is 1:1. The three-necked flask is placed on a temperature-controlled magnetic stirrer, and the upper part of the three-necked flask is condensed and refluxed with a condenser, and the magnetic stirrer and heating device are started to start the reaction. The reaction temperature was controlled at about 68°C. After 5 hours of reaction, the conversion rate of cyclopentanone was 72.45%, the selectivity of δ-valerolactone was 94.32%, the selectivity of 5-hydroxyvaleric acid was 2.62%, and the selectivity of glutaric acid The selectivity is 3.29%.

Example 6

Catalyst preparation process: get 10 grams of titanium-silicon molecular sieves with hollow grains (produced by Hunan Jianchang Petrochemical Company, brand HTS, which is MFI structure through X-ray diffraction analysis, the adsorption isotherm and desorption isotherm of the low-temperature nitrogen adsorption of this molecular sieve There is a hysteresis ring between them, the grains are hollow grains and the radial length of the cavity part is 15-180 nanometers; the molecular sieve sample is measured under the conditions of 25 °C, P/P ₀ =0.10, and adsorption time of 1 hour Benzene adsorption capacity is 78 mg/gram), 7.7 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 3.5 grams of magnesium chloride hexahydrate MgCl ₂ 6H ₂ O were added to the mortar, ground and mixed, and then transferred to The crucible was transferred to a muffle furnace for calcination at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -HTS (x=0.01, y=0.007).

The process of catalytic oxidation of cyclic ketones: Weigh 2.53 grams of magnesium and aluminum modified titanium silicon molecular sieve xMgO-yAl ₂ O ₃ -HTS (x=0.01, y=0.007) into a 100ml three-necked flask, and then add magnetic stirring Son, 19.63 gram cyclopentanone, 32 gram acetone and 46ml concentration are 30% hydrogen peroxide, and the mol ratio of cyclopentanone and hydrogen peroxide is 1: 2 now. The three-necked flask is placed on a temperature-controlled magnetic stirrer, and the upper part of the three-necked flask is condensed and refluxed with a condenser, and the magnetic stirrer and heating device are started to start the reaction. The reaction temperature was controlled at about 72°C. After 4 hours of reaction, the conversion rate of cyclopentanone was 65.28%, the selectivity of generating δ-valerolactone was 92.53%, the selectivity of 5-hydroxyvaleric acid was 2.33%, and the selectivity of pentadiene Acid selectivity was 1.94%.

Example 7

Catalyst preparation process: Take 10 grams of TS-1 titanium silicate molecular sieve ("Zeolites, 1992, Vol.12 pages 943-950"), 12 grams of crystalline aluminum nitrate nonahydrate Al(NO ₃ ) ₃ 9H ₂ O and 4.8 grams Magnesium chloride hexahydrate MgCl ₂ 6H ₂ O was added to a mortar, ground and mixed, then transferred to a crucible, transferred to a muffle furnace and roasted at 550°C for 4 hours, and the product was recovered. The obtained catalyst was expressed as xMgO-yAl ₂ O ₃ -TS-1 (x=0.024, y=0.016).

The process of catalytic oxidation of cyclic ketones: Weigh 2.3 grams of magnesium and aluminum modified titanium silicon molecular sieve xMgO-yAl ₂ O ₃ -TS-1 (x=0.024, y=0.016) into a 100ml three-necked flask, and then add Magnetic stirring bar, 19.63 grams of cyclopentanone, 3.6 grams of water and 46 ml of 30% hydrogen peroxide, the molar ratio of cyclopentanone to hydrogen peroxide is 1:2. The three-necked flask is placed on a temperature-controlled magnetic stirrer, and the upper part of the three-necked flask is condensed and refluxed with a condenser, and the magnetic stirrer and heating device are started to start the reaction. The reaction temperature was controlled at about 80°C. After 12 hours of reaction, the conversion rate of cyclopentanone was 63.26%, the selectivity of δ-valerolactone was 11.32%, the selectivity of 5-hydroxypentanoic acid was 46.76%, and the selectivity of glutaric acid The selectivity is 40.51%.

Claims (18)

1. a kind of method of magnesium and aluminum-modified titanium silicon molecular sieve catalysis oxidation cyclic ketone, it is characterized in that according to cyclic ketone: solvent: the molar proportion of hydrogen peroxide=1: (0～80): (0.2～20), temperature It is 5～200 ℃, under the condition that reaction pressure is 0.1～3.0MPa, carry out reaction and recover product in the presence of a catalyst, the mass ratio of catalyst and cyclic ketone is 1: (5～300), and said catalyst is It is obtained by modifying titanium-silicon molecular sieves with magnesium and aluminum. The mass ratio of magnesium to titanium-silicon molecular sieves in terms of MgO is x, x= _0.001-0.99 , and the mass ratio of aluminum to titanium-silicon molecular sieves in terms of _Al2O3 is y. y = 0.001 to 0.99. 2. The method according to claim 1, wherein said x=0.005-0.5, said y=0.005-0.5, and the ratio of x and y is between 0.1-5. 3. The method according to claim 2, wherein said x=0.005-0.15, said y=0.005-0.15, and the ratio of x and y is between 0.5-2. 4. according to the method for claim 1, wherein, said titanium-silicon molecular screening is selected from the mixture of one or more in TS-1, TS-2, Ti-BETA and Ti-MCM-22. 5. The method according to claim 1, wherein said titanium silicon molecular sieve is TS-1. 6. according to the method for claim 5, wherein said TS-1 has hollow grain, the radial length of the cavity part of hollow grain is 2～300 nanometers, at 25 ℃, P/P ₀ =0.10 and adsorption The measured benzene adsorption amount under the condition of 1 hour time is at least 70 mg/g, and there is a hysteresis loop between the adsorption isotherm and the desorption isotherm of low-temperature nitrogen adsorption. 7. according to the method for claim 1, it is characterized in that said catalyzer is that magnesium and aluminum obtain by modifying titanium silicon molecular sieve by solid-state ion migration method. 8. according to the method for claim 7, wherein, said solid-state ion transfer method comprises according to titanium silicon molecular sieve: crystalline acid metal aluminum salt: crystalline alkaline metal magnesium salt=100: (0.01～100): (0.01～100) The proportion of titanium-silicon molecular sieves, crystalline acidic metal aluminum salts and crystalline basic metal magnesium salts is added to a mortar, ground and mixed, then transferred to a crucible, and the product is processed and recovered under roasting conditions, wherein the titanium-silicon molecular sieve is The crystalline acid metal aluminum salt is calculated in Al ₂ O ₃ grams, and the crystalline basic metal magnesium salt is calculated in MgO. 9. according to the method for claim 1, it is characterized in that said catalyzer is prepared through following process: according to titanium silicon molecular sieve: crystalline acid metal aluminum salt: crystalline basic metal magnesium salt=100: (0.0001～100): (0.0001-100), mixing titanium-silicon molecular sieves, crystalline acidic metal aluminum salts and crystalline basic metal magnesium salts with water and evenly impregnating them, then drying and roasting to recover the product. 10. The method according to claim 1, wherein said cyclic ketones include monocyclic ketones, polycyclic ketones or cyclic ketones with side chain alkyl functional groups R. 11. The method according to claim 1, wherein said cyclic ketone is selected from cyclohexanone, cyclopentanone or methylcyclohexanone. 12. according to the method for claim 1, wherein, said hydrogen peroxide concentration is 10～60% with hydrogen peroxide mass meter concentration. 13. The method according to claim 1, characterized in that inert organic substances and/or water are selected as solvents. 14. The method according to claim 1, wherein said inert organic substance is a compound with a boiling point close to the reactant or a compound with high polarity and high dielectric constant. 15. according to the method for claim 1, wherein, cyclic ketone: the molar ratio of hydrogen peroxide is 1: (0.2～10), the mass ratio of catalyst and cyclic ketone is 1: 5～100, the molar ratio of solvent and cyclic ketone The ratio is (0.2~10):1, and the pressure is 0.1~0.5MPa. 16. The method according to claim 15, wherein acetone or dioxane is used as a solvent, and the temperature is 20-75°C. 17. The method according to claim 15, wherein ethanol or ethyl acetate is used as a solvent, the temperature is 80-95° C., and the reaction time is between 3 and 6 hours. 18. The method according to claim 15, wherein acetic acid or propionic acid is used as a solvent, the temperature is 100-160° C., the molar ratio of hydrogen peroxide to ketone is higher than 3, and the reaction time is more than 5 hours.