C9 mixed aromatic hydrocarbon production catalyst for producing mesitylene and preparation method thereof

Abstract

The present application relates to the technical field of catalyst preparation, and is a catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons and a preparation method thereof.The former is a non-noble metal supported molecular sieve catalyst, the catalyst carrier comprises a molecular sieve and a binder, the molecular sieve accounts for 70% to 90% of the weight percentage of the catalyst carrier, the loading of each element accounts for 1wt% to 10wt% of the weight percentage of the catalyst carrier, and the total loading of elements accounts for 5wt% to 15wt% of the weight percentage of the catalyst carrier.The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons has good catalytic performance, is applied to the process of producing mesitylene from C9 mixed aromatic hydrocarbons as a catalyst for alkylation reaction and isomerization reaction, finally eliminates the interference of methyl ethyl benzene, maximizes the production of mesitylene, the content of methyl ethyl benzene is less than 0.5%, and the yield of mesitylene is greater than 25%.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalyst preparation, and is a catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons and a preparation method thereof. BACKGROUND

[0002] Since C9 mixed aromatic hydrocarbons have nine isomers, after separation, only mesitylene, trimethylbenzene, m-ethyl-methylbenzene and p-ethyl-methylbenzene can be used as products in industry, among which, the added value of mesitylene is the largest. Mesitylene (1,3,5-trimethylbenzene) is an important chemical raw material, and many dye intermediates and important fine chemical products can be prepared based on it, such as pyromellitic dianhydride, mesitylene aniline, trimesic acid and terpineol.

[0003] The industrial production methods of mesitylene mainly include a synthetic method and a separation and purification method. In the synthetic method, mesitylene is generated by isomerization of trimethylbenzene as raw material (trimethylbenzene is also separated from C9 mixed aromatic hydrocarbons in reforming or cracking), and in the separation and purification method, mesitylene is directly separated and extracted from C9 mixed aromatic hydrocarbons as raw material, which is by-produced in a catalytic reforming device or a p-xylene device. According to the existing technology, the difficulty in producing and separating trimethylbenzene is that there are C9 aromatic hydrocarbon isomers such as methyl-ethylbenzene and propylbenzene and many substances such as butylbenzene in the raw material, the boiling points of part of C9 and above aromatic hydrocarbons are very close to that of trimethylbenzene, the boiling point difference between mesitylene and o-ethyl-methylbenzene is only 0.3℃, and it is impossible to use the method of rectification in industry, and the boiling points of mesitylene and p-ethyl-methylbenzene and m-ethyl-methylbenzene are also very close, so the separation difficulty is very large, and the industrial production of mesitylene is also mainly interfered by methyl-ethylbenzene, therefore, the separation and purification difficulty is very large, and the separation cost is very high, and the methods such as alkylation and isomerization can be used to separate and purify the components by using the structural difference between methyl-ethylbenzene and trimethylbenzene and by means of chemical reaction.

[0004] The Chinese patent document with the publication number CN103772121A discloses a method for cracking and producing trimethylbenzene from C9 and above heavy aromatic hydrocarbon components, which enriches trimethylbenzene in C9 aromatic hydrocarbons by means of hydrogenation dealkylation and transalkylation with light aromatic hydrocarbons, and separates light hydrocarbon, BTX (benzene, toluene and xylene) product, mesitylene and trimethylbenzene fraction, carbon nine aromatic hydrocarbon and continuous trimethylbenzene fraction, so that non-aromatic hydrocarbons and heavy aromatic hydrocarbons are cracked, the separation difficulty is reduced, but the product mesitylene cannot be obtained, the yield of light hydrocarbon and BTX product is high, the yield of trimethylbenzene is low, and the value of the product needs to be further improved.

[0005] The Chinese patent document with publication number CN1139095A discloses a method for separating and preparing mesitylene from C9 mixed aromatic hydrocarbons. First, C9 mixed aromatic hydrocarbon raw materials with a content of ethylbenzene greater than 22% are subjected to preliminary rectification. Then, a mixed fraction containing mesitylene, trimethylbenzene, and ortho-, meta-, and para-ethylbenzene is added as a reaction raw material, and t-butyl alcohol, concentrated sulfuric acid, aluminum trichloride, and hydrochloric acid are added. After alkylation reaction and settling treatment, the ethylbenzene is converted into high-boiling substances, and then subjected to rectification separation to obtain a mesitylene product with a purity greater than 98%. However, this method converts a large amount of trimethylbenzene into alkyl aromatic hydrocarbons with more carbon numbers, resulting in the loss of trimethylbenzene. Moreover, the method causes severe corrosion of equipment, making it difficult to apply in industry.

[0006] The Chinese patent document with publication number CN1313269A discloses a process for separating high-purity trimethylbenzene from heavy aromatic hydrocarbons. The heavy aromatic hydrocarbons from a refinery reformer are subjected to continuous rectification separation in two packed towers to obtain a high-purity trimethylbenzene fraction. However, high-purity mesitylene cannot be obtained.

[0007] The Chinese patent document with publication number CN1974500A discloses a trimethylbenzene serial separation device and method. The method uses a three-tower serial process to separate heavy aromatic hydrocarbons from a reformer, producing high-purity trimethylbenzene and co-producing enriched mesitylene with a purity greater than 35%. The purity of single mesitylene is low.

[0008] Wang Ming et al. from Tianjin University conducted research on the isomerization of high-purity trimethylbenzene to produce mesitylene. Zeolite mordenite was used as a carrier to load Ni / Mo or Ni / La metal components to inhibit carbon deposition, resulting in good activity and stability and prolonging the service life of the catalyst. Cheng Xiaojing et al. from Dalian University of Technology studied the reaction rules of C9 aromatic hydrocarbons on ZSM-5, HMOR, and Hβ zeolite molecular sieves. In the A9 reaction, HZSM-5 molecular sieves showed strong cracking ability and could inhibit the disproportionation of A9. Alkylation reactions were prone to occur on Hβ zeolite and HMOR zeolite. Their research on A9 on nano-ZSM-5 molecular sieves showed that the content of trimethylbenzene decreased from 65.13% to 22.73%, the BTX yield reached 71.53%, the trimethylbenzene yield was low, and the content of ethylbenzene in the product was high, which was not conducive to the separation of trimethylbenzene.

[0009] Currently, in the existing process for separating C9 mixed aromatic hydrocarbons to produce mesitylene, the existing molecular sieve catalysts have poor catalytic performance, leading to high interference of ethylbenzene in the dealkylation reaction and isomerization reaction of C9 mixed aromatic hydrocarbons, and low yield of mesitylene products. SUMMARY

[0010] The application provides a catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons and a preparation method thereof.

[0011] One of the technical solutions of the application is achieved by the following measures: a catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons, which is a non-noble metal supported molecular sieve catalyst, the catalyst carrier comprises a molecular sieve and a binder, the molecular sieve accounts for 70% to 90% of the weight percentage of the catalyst carrier, the non-noble metal elements are one or more of Fe, W, Mo, Ni, Zn, La and K, the loading of each element accounts for 1wt% to 10wt% of the weight percentage of the catalyst carrier, and the total loading of the elements accounts for 5wt% to 15wt% of the weight percentage of the catalyst carrier.

[0012] The following is a further optimization or / and improvement of one of the above technical solutions:

[0013] The above-mentioned molecular sieve is a self-made molecular sieve, the self-made molecular sieve is one or more of a self-made hydrogen type ZSM-5 molecular sieve, a self-made hydrogen type mordenite molecular sieve and a self-made hydrogen type beta zeolite molecular sieve, and the binder is one of gamma alumina and pseudo-boehmite.

[0014] In the above-mentioned molecular sieve, the aluminum source is one of sodium metaaluminate and sodium aluminate, the template agent is one of n-butylamine, tetrapropylammonium bromide, triethanolamine, tetraethylammonium bromide and tetraethylammonium hydroxide, the alkali source is one of sodium hydroxide and sodium chloride, and the silicon source is one of silica gel and silicon dioxide.

[0015] The above-mentioned self-made hydrogen type ZSM-5 molecular sieve is obtained by the following method:

[0016] S1, 0.5 to 1.5 parts by weight of an aluminum source, 5 to 20 parts of a template agent, 1 to 2 parts of an alkali source and 15 to 30 parts of a silicon source are dissolved in 60 to 110 parts of deionized water, and then the mixture is fully stirred to obtain a mixture, then the mixture is crystallized at 100 to 170 DEG C for 10 to 36 hours to obtain a crystallization product, and finally the crystallization product is subjected to suction filtration, washing, drying and calcination to obtain a sodium type ZSM-5 molecular sieve;

[0017] S2, the sodium type ZSM-5 molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain a self-made hydrogen type ZSM-5 molecular sieve.

[0018] The above-mentioned self-made hydrogen type mordenite molecular sieve is obtained by the following method:

[0019] S1, 1-10 parts by weight of an aluminum source, 2-20 parts of a template agent, 1-3 parts of an alkali source and 20-60 parts of a silicon source are dissolved in 100-310 parts of deionized water to obtain a mixture, then the mixture is crystallized at 180 DEG C for 48 hours to obtain a crystallization product; finally, the crystallization product is filtered, washed, dried and calcined to obtain a sodium-type mordenite molecular sieve;

[0020] S2, the sodium-type mordenite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain a self-made hydrogen-type mordenite molecular sieve.

[0021] The self-made hydrogen-type beta zeolite molecular sieve is obtained by the following method:

[0022] S1, 0.5-1 parts by weight of an aluminum source, 30-35 parts of a template agent and 40-50 parts of a silicon source are dissolved in 100-110 parts of deionized water to obtain a mixture, then the mixture is crystallized at 140 DEG C for 72 hours to obtain a crystallization product; finally, the crystallization product is filtered, washed, dried and calcined to obtain a sodium-type beta zeolite molecular sieve;

[0023] S2, the sodium-type beta zeolite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain a self-made hydrogen-type beta zeolite molecular sieve.

[0024] The C9 mixed aromatic hydrocarbon production mesitylene catalyst is obtained by the following method:

[0025] Firstly, the molecular sieve and the binder are uniformly mixed in a mass ratio of 4:1, then a pore-forming agent is added and uniformly mixed, the mixture is extruded into a strip by 1-4% dilute nitric acid, and then the catalyst carrier is obtained after drying and calcination; wherein the addition amount of the pore-forming agent is 1-2% of the total weight of the molecular sieve and the binder, and the pore-forming agent is sesbania powder;

[0026] Secondly, the catalyst carrier is loaded with the impregnation liquid containing non-noble metal by the equal volume impregnation method, and then the C9 mixed aromatic hydrocarbon production mesitylene catalyst is obtained after drying and calcination.

[0027] In the second step, the impregnation time is 2-24 hours, the calcination temperature is 450-580 DEG C, and the calcination time is 2-10 hours.

[0028] The second technical solution of the application is realized by the following measures: a C9 mixed aromatic hydrocarbon production mesitylene catalyst is prepared by the following method:

[0029] Firstly, the molecular sieve and the binder with a mass ratio of 4:1 are uniformly mixed, then a pore forming agent is added and uniformly mixed, and then the catalyst carrier is obtained by extruding the mixture through dilute nitric acid with a mass concentration of 1% to 4%, and then drying and calcining; wherein the addition amount of the pore forming agent is 1% to 2% of the total weight of the molecular sieve and the binder, and the pore forming agent is eudragit.

[0030] Secondly, the catalyst carrier is loaded with the impregnation liquid containing non-noble metal through the equal volume impregnation method, and then the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons is obtained by drying and calcining.

[0031] The third technical solution of the present application is realized by the following measures: the application of the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons in the production of mesitylene from C9 mixed aromatic hydrocarbons.

[0032] The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons has good catalytic performance, and is used as a catalyst for alkylation reaction and isomerization reaction in the process of producing mesitylene from C9 mixed aromatic hydrocarbons, which finally eliminates the interference of methyl ethyl benzene, maximizes the production of mesitylene, and has a methyl ethyl benzene content of less than 0.5% and a mesitylene yield of more than 25%, effectively solving the problem of low mesitylene product yield caused by insufficient catalytic performance of the existing catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons. DETAILED DESCRIPTION

[0033] The present application is not limited by the following examples, and the specific implementation can be determined according to the technical solution of the present application and the actual situation. In the present application, various chemical reagents and chemical products mentioned are well-known and commonly used chemical reagents and chemical products in the prior art unless otherwise specified; the percentages in the present application are mass percentages unless otherwise specified; the solutions in the present application are aqueous solutions with water as the solvent unless otherwise specified, for example, a hydrochloric acid solution is an aqueous hydrochloric acid solution; the normal temperature and room temperature in the present application generally refer to a temperature of 15℃ to 25℃, which is generally defined as 25℃.

[0034] The present application will be further described below in conjunction with examples:

[0035] Example 1: The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons is a non-noble metal loaded molecular sieve catalyst, the catalyst carrier includes molecular sieve and binder, the molecular sieve accounts for 70% to 90% of the weight percentage of the catalyst carrier, the non-noble metal elements are one or more of Fe, W, Mo, Ni, Zn, La and K, the loading amount of each element accounts for 1wt% to 10wt% of the weight percentage of the catalyst carrier, and the total element loading amount accounts for 5wt% to 15wt% of the weight percentage of the catalyst carrier.

[0036] Embodiment 2: As an optimization of the above-mentioned embodiments, the molecular sieve is one or more of a self-made hydrogen-type ZSM-5 molecular sieve, a self-made hydrogen-type mordenite molecular sieve and a self-made hydrogen-type β zeolite molecular sieve, and the binder is one of gamma alumina and pseudoboehmite.

[0037] Embodiment 3: As an optimization of the above-mentioned embodiments, in the molecular sieve, the aluminum source is one of sodium metaaluminate and sodium aluminate, the template agent is one of n-butylamine, tetrapropylammonium bromide, triethanolamine, tetraethylammonium bromide and tetraethylammonium hydroxide, the alkali source is one of sodium hydroxide and sodium chloride, and the silicon source is one of silica gel and silicon dioxide.

[0038] Embodiment 4: As an optimization of the above-mentioned embodiments, the self-made hydrogen-type ZSM-5 molecular sieve is obtained by the following method:

[0039] S1, 0.5-1.5 parts by weight of an aluminum source, 5-20 parts of a template agent, 1-2 parts of an alkali source and 15-30 parts of a silicon source are dissolved in 60-110 parts of deionized water, and the mixture is fully stirred to obtain a mixture, then the mixture is crystallized at 100-170℃ for 10-36h to obtain a crystallization product; finally, the crystallization product is subjected to suction filtration, washing, drying and calcination to obtain a sodium-type ZSM-5 molecular sieve;

[0040] S2, the sodium-type ZSM-5 molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain a self-made hydrogen-type ZSM-5 molecular sieve.

[0041] Embodiment 5: As an optimization of the above-mentioned embodiments, the self-made hydrogen-type mordenite molecular sieve is obtained by the following method:

[0042] S1, 1-10 parts by weight of an aluminum source, 2-20 parts of a template agent, 1-3 parts of an alkali source and 20-60 parts of a silicon source are dissolved in 100-310 parts of deionized water, and the mixture is fully stirred to obtain a mixture, then the mixture is crystallized at 180℃ for 48h to obtain a crystallization product; finally, the crystallization product is subjected to suction filtration, washing, drying and calcination to obtain a sodium-type mordenite molecular sieve;

[0043] S2, the sodium-type mordenite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain a self-made hydrogen-type mordenite molecular sieve.

[0044] Embodiment 6: As an optimization of the above-mentioned embodiments, the self-made hydrogen-type β zeolite molecular sieve is obtained by the following method:

[0045] S1, 0.5 to 1 parts by weight of an aluminum source, 30 to 35 parts of a template agent, and 40 to 50 parts of a silicon source were dissolved in 100 to 110 parts of deionized water, and the mixture was stirred to obtain a mixture, then the mixture was crystallized at 140°C for 72h to obtain a crystallized product; finally, the crystallized product was filtered, washed, dried, and calcined to obtain a sodium-type beta zeolite molecular sieve;

[0046] S2, the sodium-type beta zeolite molecular sieve was sequentially subjected to alkali treatment and ammonium exchange to obtain a self-made hydrogen-type beta zeolite molecular sieve.

[0047] Example 7: As an optimization of the above examples, the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons was obtained by the following method:

[0048] First, the molecular sieve and the binder were mixed in a mass ratio of 4:1, then the pore-forming agent was added and mixed, and then the mixture was extruded into a strip by using dilute nitric acid with a mass concentration of 1% to 4%, and then the catalyst carrier was obtained after drying and calcination; wherein the addition amount of the pore-forming agent is 1% to 2% of the total weight of the molecular sieve and the binder, and the pore-forming agent is Euphorbia powder;

[0049] Second, the catalyst carrier was loaded with an impregnation liquid containing a non-noble metal by an equal-volume impregnation method, and then the C9 mixed aromatic hydrocarbon production mesitylene catalyst was obtained after drying and calcination.

[0050] Example 8: As an optimization of the above examples, in the second step, the impregnation time is 2h to 24h, the calcination temperature is 450°C to 580°C, and the calcination time is 2h to 10h.

[0051] Example 9:

[0052] The self-made molecular sieve is a self-made hydrogen-type ZSM-5 molecular sieve, which is obtained by the following method:

[0053] S1, 0.492g of sodium metaaluminate, 5.265g of n-butylamine, 1.96g of sodium hydroxide, and 17.505g of silica gel were sequentially added to 60.384g of deionized water, and the mixture was stirred to obtain a mixture, then the mixture was crystallized in a crystallization kettle at 170°C for 36h, and then the crystallized product was obtained after filtration, washing, drying, and calcination; and finally, the Na-type ZSM-5 molecular sieve was obtained.

[0054] S2, the sodium-type ZSM-5 molecular sieve was subjected to alkali treatment by adding 300g of a 0.2mol / L NaOH solution, stirring was started, and the mixture was treated at 85°C for 2h, then the treated ZSM-5 molecular sieve was filtered, washed, and dried to obtain an alkali-treated ZSM-5 molecular sieve; the alkali-treated ZSM-5 molecular sieve was subjected to ammonium exchange by being placed in a 1mol / L ammonium chloride solution and stirring at 85°C for 4h, and then the self-made hydrogen-type ZSM-5 molecular sieve was obtained after filtration, washing, drying, and calcination.

[0055] The C9 mixed aromatic hydrocarbon production catalyst for producing mesitylene is obtained by the following method:

[0056] In the first step, self-made hydrogen type ZSM-5 molecular sieve and a binder in a mass ratio of 4:1 are uniformly mixed, and then Euphorbia powder is added and uniformly mixed. The catalyst carrier is obtained by extruding the mixture through 4% dilute nitric acid, and then drying and calcining, wherein the addition amount of the Euphorbia powder is 2% of the total weight of the hydrogen type ZSM-5 molecular sieve and the binder.

[0057] In the second step, the catalyst carrier is loaded with an impregnation liquid containing non-noble metals (nickel oxide solution and molybdenum oxide solution) by an equal volume impregnation method, and then dried and calcined at 500°C for 6h to obtain a molecular sieve catalyst loaded with 0.5wt% Ni and 2.0wt% Mo, which is denoted as catalyst 1.

[0058] Comparative Example 1:

[0059] The difference from Example 9 is that the self-made molecular sieve is replaced by a commercially available ZSM-5 molecular sieve, and a molecular sieve catalyst loaded with 0.5wt% Ni and 2.0wt% Mo is obtained by the preparation method of the C9 mixed aromatic hydrocarbon production catalyst for producing mesitylene, which is denoted as Comparative Example 1.

[0060] Example 10:

[0061] The difference from Example 9 is that in the preparation of the catalyst, the second step is changed to “the catalyst carrier is loaded with an impregnation liquid containing non-noble metals (nickel oxide solution and tungsten oxide solution) by an equal volume impregnation method, and then dried and calcined at 540°C for 4h to obtain a molecular sieve catalyst loaded with 1.0wt% Ni and 3.0wt% W, which is denoted as catalyst 2”.

[0062] Example 11:

[0063] The self-made molecular sieve is a self-made hydrogen type mordenite molecular sieve, which is obtained by the following method:

[0064] S1, 1.35g of sodium metaaluminate, 18.867g of triethanolamine, 1.067g of sodium hydroxide and 20g of solid silicon dioxide are sequentially added to 102g of deionized water, and after being fully stirred, they are put into a crystallization kettle and crystallized at 180°C for 48h. After crystallization, the Na type mordenite molecular sieve is obtained by suction filtration, washing, drying and calcination.

[0065] S2, the sodium type mordenite molecular sieve is subjected to alkali treatment, 300g of a 0.2mol / L NaOH solution is added, stirring is started, and treatment is carried out at 85℃ for 2h; after the treatment, suction filtration and washing are carried out to obtain the ZSM-5 molecular sieve after alkali treatment; the ZSM-5 molecular sieve after alkali treatment is subjected to ammonium exchange, is placed in a 0.5mol / L ammonium chloride solution, is stirred at 85℃ for 4h, is filtered, washed, dried and calcined to obtain the self-made hydrogen type mordenite molecular sieve.

[0066] The catalyst for producing mesitylene from the C9 mixed aromatic hydrocarbons is obtained by the following method:

[0067] In the first step, the self-made hydrogen type ZSM-5 molecular sieve and the binder are uniformly mixed in a mass ratio of 4:1, and then the sesbania powder is added and uniformly mixed; the mixture is extruded into a strip by using a 4% dilute nitric acid solution, and then the catalyst carrier is obtained after drying and calcination; wherein the addition amount of the sesbania powder is 2% of the total weight of the hydrogen type ZSM-5 molecular sieve and the binder.

[0068] In the second step, the catalyst carrier is loaded with the impregnation solution containing non-noble metals (nickel oxide solution and molybdenum oxide solution) by the equal volume impregnation method, and then the molecular sieve catalyst loaded with 1.0wt% Ni and 3.0wt% Mo is obtained after drying and calcination at 500℃ for 6h, which is recorded as catalyst 3.

[0069] Example 12:

[0070] The difference between the example 11 of the present application and the example 12 of the present application is that in the preparation of the catalyst, the second step is changed to “the catalyst carrier is loaded with the impregnation solution containing non-noble metals (iron oxide solution and tungsten oxide solution) by the equal volume impregnation method, and then the molecular sieve catalyst loaded with 0.5wt% Fe and 2.5wt% W is obtained after drying and calcination at 540℃ for 4h, which is recorded as catalyst 4”.

[0071] Example 13:

[0072] The self-made molecular sieve is a self-made hydrogen type β zeolite molecular sieve, which is obtained by the following method:

[0073] In S1, 0.62g of sodium aluminate, 31.375g of tetraethylammonium hydroxide and 48g of solid silicon dioxide are sequentially added to 106.36g of deionized water, and after being fully stirred, they are placed in a crystallization kettle and crystallized at 140℃ for 72h; after the crystallization is completed, suction filtration, washing, drying and calcination are carried out to obtain the Na type β zeolite molecular sieve;

[0074] S2, the sodium type ZSM-5 molecular sieve is subjected to alkali treatment, 300g of NaOH solution with a concentration of 0.2mol / L is added, stirring is started, and treatment is carried out at 85℃ for 2h; after treatment, suction filtration and washing are carried out to obtain the ZSM-5 molecular sieve after alkali treatment; the ZSM-5 molecular sieve after alkali treatment is subjected to ammonium exchange, is placed in 1mol / L of ammonium chloride solution, stirring is carried out at 85℃ for 4h, and filtration, washing, drying and calcination are carried out to obtain the self-made hydrogen type ZSM-5 molecular sieve.

[0075] The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons is obtained by the following method:

[0076] In the first step, the self-made hydrogen type ZSM-5 molecular sieve and the binder are uniformly mixed in a mass ratio of 4:1, and then the sesbania powder is added and uniformly mixed; the mixture is extruded into a strip through dilute nitric acid with a concentration of 4%, and then the catalyst carrier is obtained after drying and calcination; wherein the addition amount of the sesbania powder is 1% of the total weight of the hydrogen type ZSM-5 molecular sieve and the binder;

[0077] In the second step, the catalyst carrier is loaded with the impregnation liquid containing non-noble metals (tungsten oxide solution, nickel oxide solution and lanthanum oxide solution) by the equal volume impregnation method, and then the molecular sieve catalyst loaded with 3.0% W, 2.0% Ni and 0.5% La is obtained after drying and calcination at 500℃ for 6h, which is recorded as catalyst 5.

[0078] Example 14:

[0079] The self-made molecular sieve is the self-made hydrogen type ZSM-5 molecular sieve, which is obtained by the following method:

[0080] In S1, 1.215g of sodium metaaluminate, 19.145g of tetrapropylammonium bromide, 1.20g of sodium hydroxide and 30g of silica gel are sequentially added to 108g of deionized water, and after being fully stirred, they are placed in a crystallization kettle for crystallization at 100℃ for 10h and then at 160℃ for 24h; after crystallization, suction filtration, washing, drying and calcination are carried out to obtain the ZSM-5 molecular sieve in the sodium type;

[0081] In S2, the sodium type ZSM-5 molecular sieve is subjected to alkali treatment, 300g of NaOH solution with a concentration of 0.2mol / L is added, stirring is started, and treatment is carried out at 85℃ for 2h; after treatment, suction filtration and washing are carried out to obtain the ZSM-5 molecular sieve after alkali treatment; the ZSM-5 molecular sieve after alkali treatment is subjected to ammonium exchange, is placed in 1mol / L of ammonium chloride solution, stirring is carried out at 85℃ for 4h, and filtration, washing, drying and calcination are carried out to obtain the self-made hydrogen type ZSM-5 molecular sieve.

[0082] The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons is obtained by the following method:

[0083] Firstly, self-made hydrogen type ZSM-5 molecular sieve and a binder in a mass ratio of 4:1 were uniformly mixed, and then Euphorbia powder was added and uniformly mixed, and then the mixture was extruded into a strip by using 4% dilute nitric acid, and then the catalyst carrier was obtained after drying and calcination; wherein the addition amount of Euphorbia powder is 1% of the total weight of hydrogen type ZSM-5 molecular sieve and the binder;

[0084] Secondly, the catalyst carrier was loaded with an impregnation solution containing non-precious metals (molybdenum oxide solution and nickel oxide solution) by an equal volume impregnation method, and then the molecular sieve catalyst loaded with 4.0% W and 1.0% Ni was obtained after drying and calcination at 520℃ for 6h, and was recorded as catalyst 6.

[0085] Comparative example 2:

[0086] The difference between comparative example 2 and example 14 is that the self-made molecular sieve is replaced by a commercially available ZSM-5 molecular sieve, and then the molecular sieve catalyst loaded with 4.0% W and 1.0% Ni is obtained according to the preparation method of the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons, and is recorded as comparative example 2.

[0087] Example 15:

[0088] The difference between example 15 and example 9 is that in the preparation of the catalyst, the second step is changed to "the catalyst carrier is loaded with an impregnation solution containing non-precious metals (nickel oxide solution and molybdenum oxide solution) by an equal volume impregnation method, and then the molecular sieve catalyst loaded with 2.0% Ni and 8.0% Mo is obtained after drying and calcination at 540℃ for 4h, and is recorded as catalyst 7".

[0089] Example 16:

[0090] The self-made molecular sieve is a self-made hydrogen type mordenite molecular sieve, which is obtained according to the following method:

[0091] S1, 8.11g of sodium metaaluminate, 2.10g of tetraethylammonium bromide, 2.34g of sodium chloride and 60.0g of silica gel were sequentially added to 306g of deionized water, and after being fully stirred, they were put into a crystallization kettle and crystallized at 180℃ for 48h. After the crystallization was completed, the product was subjected to suction filtration, washing, drying and calcination to obtain a Na type mordenite molecular sieve;

[0092] S2, the Na type mordenite molecular sieve was subjected to alkali treatment, 300g of 0.2mol / L NaOH solution was added, stirring was started, and the mixture was treated at 85℃ for 2h. After the treatment, suction filtration and washing were performed to obtain the ZSM-5 molecular sieve after alkali treatment. The ZSM-5 molecular sieve after alkali treatment was subjected to ammonium exchange by being put into 1mol / L ammonium chloride solution and stirring at 85℃ for 4h, and then was subjected to filtration, washing, drying and calcination to obtain the self-made hydrogen type mordenite molecular sieve.

[0093] The C9 mixed aromatic hydrocarbon production catalyst for producing mesitylene is obtained by the following method:

[0094] In the first step, self-made hydrogen type ZSM-5 molecular sieve and a binder are mixed in a mass ratio of 4:1, and then amaranth powder is added and mixed, and the mixture is extruded into a strip by using dilute nitric acid with a concentration of 4%, and then the catalyst carrier is obtained after drying and calcination; wherein the addition amount of amaranth powder is 2% of the total weight of hydrogen type ZSM-5 molecular sieve and the binder;

[0095] In the second step, the catalyst carrier is loaded with an impregnation solution containing non-noble metals (iron oxide solution and molybdenum oxide solution) by an equal volume impregnation method, and then a molecular sieve catalyst loaded with 1.0% Fe and 4.0% Mo is obtained after drying and calcination at 540°C for 6h, which is recorded as catalyst 8.

[0096] Example 17:

[0097] The difference between the present application and example 11 is that in the preparation of the catalyst, the second step is changed to "the catalyst carrier is loaded with an impregnation solution containing non-noble metals (nickel oxide solution, molybdenum oxide solution and lanthanum oxide solution) by an equal volume impregnation method, and then a molecular sieve catalyst loaded with 0.5% Ni, 3.0% Mo and 0.2% La is obtained after drying and calcination at 540°C for 4h, which is recorded as catalyst 9".

[0098] Example 18:

[0099] The self-made molecular sieve is composed of self-made hydrogen type mordenite molecular sieve prepared by example 11 of the present application and self-made hydrogen type β zeolite molecular sieve prepared by example 13 of the present application in a mass ratio of 1:1.

[0100] The C9 mixed aromatic hydrocarbon production catalyst for producing mesitylene is obtained by the following method:

[0101] In the first step, self-made molecular sieve and a binder are mixed in a mass ratio of 4:1, and then amaranth powder is added and mixed, and the mixture is extruded into a strip by using dilute nitric acid with a concentration of 4%, and then the catalyst carrier is obtained after drying and calcination; wherein the addition amount of amaranth powder is 2% of the total weight of hydrogen type ZSM-5 molecular sieve and the binder;

[0102] In the second step, the catalyst carrier is loaded with an impregnation solution containing non-noble metals (potassium oxide solution and molybdenum oxide solution) by an equal volume impregnation method, and then a molecular sieve catalyst loaded with 0.5% K and 2.0% Mo is obtained after drying and calcination at 540°C for 6h, which is recorded as catalyst 10.

[0103] Example 19:

[0104] The application of the C9 mixed aromatic hydrocarbon production catalyst for producing mesitylene in the production of C9 mixed aromatic hydrocarbon is investigated.

[0105] The preparation method for producing mesitylene from C9 mixed aromatics is as follows:

[0106] S1, after mixing the required amount of C9 mixed aromatics with hydrogen, a dealkylation reaction is carried out in a dealkylation reactor packed with catalyst to obtain the dealkylation product;

[0107] S2, after the dealkylation product is sent to a high-pressure separator for gas-liquid separation, the resulting hydrogen and liquid products are recycled.

[0108] S3, the liquid product is sent to the BTX recovery tower for separation to obtain BTX and C9 and above components. The C9 and above components are sent to the mesitylene tower for separation to obtain mesitylene and C9 and above components excluding mesitylene.

[0109] S4, the C9 and above components except for mesitylene are sent to the terephthalene and terephthalene tower for further separation to obtain a mixture of C10+ heavy aromatics and terephthalene and terephthalene.

[0110] S5, a mixture of pseudotrimethylbenzene and terephthalene is fed with hydrogen into an isomerization reactor filled with catalyst to carry out an isomerization reaction, and the isomerization product is obtained. The isomerization product is returned to a high-pressure separator for gas-liquid separation, and finally the pseudotrimethylbenzene and terephthalene are converted into mesitylene.

[0111] Catalysts 1 to 5 prepared in Examples 9 to 13 of this invention were reduced and activated, then loaded into a dealkylation reactor for a dealkylation reaction, and their catalytic performance was evaluated. The dealkylation reaction conditions were a reaction temperature of 340°C and a mass hourly space velocity of 2 h⁻¹. -1 The catalytic performance of catalysts 1 to 5 was evaluated using a 4:1 molar ratio of 1.5 MPa, hydrogen, and C9 mixed aromatics. The C9 mixed aromatic feedstock consisted of 3.08% xylene, 1.39% propylbenzene, 6.22% m-toluene, 2.86% p-toluene, 13.10% mesitylene, 2.42% o-toluene, 43.84% pseudotrimethylbenzene, 7.24% terephthalene, 0.53% non-aromatics, and 19.79% C10+ heavy aromatics.

[0112] Catalysts 6 to 10 prepared in Examples 14 to 18 of this invention were reduced and activated, then loaded into an isomerization reactor for isomerization reaction, and their catalytic performance was evaluated. The isomerization reaction conditions were a reaction temperature of 300°C and a mass hourly space velocity of 1 h⁻¹. -1 The catalytic performance of catalysts 6 to 10 was evaluated using a molar ratio of 2.0 MPa, hydrogen, and C9 mixed aromatics of 4:1. The mixture of pseudotrimethylbenzene and terephthalene consisted of 86.02% pseudotrimethylbenzene, 13.50% terephthalene, 0.32% mesitylene, 0.06% o-toluene, and 0.10% C10+ heavy aromatics.

[0113] The dealkylation reaction results are shown in Table 1, and the isomerization reaction results are shown in Table 2. As shown in Table 1, the BTX product yield obtained by separating the reaction product through a BTX tower is less than 25%, the C10+ heavy aromatic product yield is less than 16%, the content of propylbenzene is reduced to 0, and the content of ethylmethylbenzene is reduced from 11.5% of the raw material to less than 0.5%. As shown in Table 2, the content of mesitylene in the reaction product catalyzed by the catalyst prepared in the comparative example 2 is increased from 0.32% of the raw material to more than 13%, while the content of mesitylene in the reaction product catalyzed by the catalyst prepared in the application is increased from 0.32% of the raw material to more than 22%, and the loss of trimethylbenzene is less than 5%. In summary, the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons has good catalytic performance in the process of producing mesitylene from C9 mixed aromatic hydrocarbons, finally eliminates the interference of ethylmethylbenzene, can maximize the production of mesitylene, the content of ethylmethylbenzene is less than 0.5%, and the total yield of mesitylene is more than 25% after reaction and separation.

[0114] In summary, the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons has good catalytic performance, and is applied in the process of producing mesitylene from C9 mixed aromatic hydrocarbons as a catalyst for alkylation reaction and isomerization reaction, finally eliminates the interference of ethylmethylbenzene, can maximize the production of mesitylene, the content of ethylmethylbenzene is less than 0.5%, and the total yield of mesitylene is more than 25%, effectively solving the problem of low mesitylene product yield caused by insufficient catalytic performance of the existing catalyst for separating and producing mesitylene from C9 mixed aromatic hydrocarbons.

[0115] The above technical features constitute embodiments of the application, which have strong adaptability and implementation effect. Non-essential technical features can be added or removed according to actual needs to meet different needs.

[0116]

Claims

1. A catalyst for producing mesitylene from a C9 mixed aromatic hydrocarbon, characterized by, The catalyst is a non-noble metal supported molecular sieve catalyst, the catalyst carrier comprises a molecular sieve and a binder, the molecular sieve accounts for 70% to 90% of the weight percentage of the catalyst carrier, the non-noble metal elements are one or more of Fe, W, Mo, Ni, Zn and La, the loading of each non-noble metal element accounts for 1wt% to 10wt% of the weight percentage of the catalyst carrier, and the total loading of the non-noble metal elements accounts for 5wt% to 15wt% of the weight percentage of the catalyst carrier; the molecular sieve is a self-made hydrogen type ZSM-5 molecular sieve, a self-made hydrogen type mordenite molecular sieve or a self-made hydrogen type beta zeolite molecular sieve; wherein, The self-made hydrogen type ZSM-5 molecular sieve is obtained by the following method: S1, dissolving 0.5 to 1.5 parts by weight of an aluminum source, 5 to 20 parts of a template agent, 1 to 2 parts of an alkali source and 15 to 30 parts of a silicon source in 60 to 110 parts of deionized water, fully stirring to obtain a mixture, then crystallizing the mixture at 100 to 170 DEG C for 10 to 36 hours to obtain a crystallization product; finally, the crystallization product is subjected to suction filtration, washing, drying and calcination to obtain a sodium type ZSM-5 molecular sieve; S2, the sodium type ZSM-5 molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain the self-made hydrogen type ZSM-5 molecular sieve; The self-made hydrogen type mordenite molecular sieve is obtained by the following method: S1, dissolving 1 to 10 parts by weight of an aluminum source, 2 to 20 parts of a template agent, 1 to 3 parts of an alkali source and 20 to 60 parts of a silicon source in 100 to 310 parts of deionized water, fully stirring to obtain a mixture, then crystallizing the mixture at 180 DEG C for 48 hours to obtain a crystallization product; finally, the crystallization product is subjected to suction filtration, washing, drying and calcination to obtain a sodium type mordenite molecular sieve; S2, the sodium type mordenite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain the self-made hydrogen type mordenite molecular sieve; The self-made hydrogen type beta zeolite molecular sieve is obtained by the following method: S1, dissolving 0.5 to 1 part by weight of an aluminum source, 30 to 35 parts of a template agent and 40 to 50 parts of a silicon source in 100 to 110 parts of deionized water, fully stirring to obtain a mixture, then crystallizing the mixture at 140 DEG C for 72 hours to obtain a crystallization product; finally, the crystallization product is subjected to suction filtration, washing, drying and calcination to obtain a sodium type beta zeolite molecular sieve; S2, the sodium type beta zeolite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain the self-made hydrogen type beta zeolite molecular sieve; In the above molecular sieve preparation method, the aluminum source is one of sodium metaaluminate and sodium aluminate, the template agent is one of n-butylamine, tetrapropylammonium bromide, triethanolamine, tetraethylammonium bromide and tetraethylammonium hydroxide, the alkali source is sodium hydroxide, and the silicon source is one of silica gel and silicon dioxide.

2. The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons according to claim 1, characterized by, The binder is one of gamma alumina and pseudo-boehmite.

3. The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons according to claim 1 or 2, characterized by, The catalyst is obtained by the following method: In the first step, the molecular sieve and the binder are mixed in a mass ratio of 4:1, and then a pore-forming agent is added and mixed, and then the mixture is extruded into a strip by using dilute nitric acid with a mass concentration of 1% to 4%, and then dried and calcined to obtain a catalyst carrier; wherein the addition amount of the pore-forming agent is 1% to 2% of the total weight of the molecular sieve and the binder, and the pore-forming agent is Euphorbia hirta powder; In the second step, the catalyst carrier is loaded with the impregnation liquid containing non-noble metals by the equal-volume impregnation method, and then dried and calcined to obtain the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons.

4. The catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons according to claim 3, characterized by, In the second step, the impregnation time is 2h to 24h, the calcination temperature is 450℃ to 580℃, and the calcination time is 2h to 10h.

5. A method for producing a catalyst for producing mesitylene from a C9 mixed aromatic hydrocarbon according to any one of claims 1 to 4, characterized by, The following methods are used: In the first step, the molecular sieve and the binder are mixed in a mass ratio of 4:1, and then a pore-forming agent is added and mixed, and then the mixture is extruded into a strip by using dilute nitric acid with a mass concentration of 1% to 4%, and then dried and calcined to obtain a catalyst carrier; wherein the addition amount of the pore-forming agent is 1% to 2% of the total weight of the molecular sieve and the binder, and the pore-forming agent is Euphorbia hirta powder; In the second step, the catalyst carrier is loaded with the impregnation liquid containing non-noble metals by the equal-volume impregnation method, and then dried and calcined to obtain the catalyst for producing mesitylene from C9 mixed aromatic hydrocarbons; The molecular sieve is a self-made hydrogen type ZSM-5 molecular sieve, a self-made hydrogen type mordenite molecular sieve, or a self-made hydrogen type β zeolite molecular sieve; wherein The self-made hydrogen type ZSM-5 molecular sieve is obtained by the following method: S1, dissolving 0.5 to 1.5 parts of an aluminum source, 5 to 20 parts of a template agent, 1 to 2 parts of an alkali source, and 15 to 30 parts of a silicon source in 60 to 110 parts of deionized water to obtain a mixture, and then crystallizing the mixture at 100 to 170℃ for 10 to 36h to obtain a crystallization product; finally, the crystallization product is filtered, washed, dried, and calcined to obtain a sodium type ZSM-5 molecular sieve; S2, the sodium type ZSM-5 molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain the self-made hydrogen type ZSM-5 molecular sieve; The self-made hydrogen type mordenite molecular sieve is obtained by the following method: S1, dissolving 1 to 10 parts of an aluminum source, 2 to 20 parts of a template agent, 1 to 3 parts of an alkali source, and 20 to 60 parts of a silicon source in 100 to 310 parts of deionized water to obtain a mixture, and then crystallizing the mixture at 180℃ for 48h to obtain a crystallization product; finally, the crystallization product is filtered, washed, dried, and calcined to obtain a sodium type mordenite molecular sieve; S2, the sodium type mordenite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain the self-made hydrogen type mordenite molecular sieve; The self-made hydrogen type β zeolite molecular sieve is obtained by the following method: S1, 0.5-1 parts of an aluminum source, 30-35 parts of a template agent and 40-50 parts of a silicon source are dissolved in 100-110 parts of deionized water, and the mixture is stirred to obtain a mixture, then the mixture is crystallized at 140°C for 72h to obtain a crystallization product; finally, the crystallization product is filtered, washed, dried and calcined to obtain a sodium type β zeolite molecular sieve; S2, the sodium type β zeolite molecular sieve is sequentially subjected to alkali treatment and ammonium exchange to obtain the self-made hydrogen type β zeolite molecular sieve; In the above molecular sieve preparation method, the aluminum source is one of sodium metaborate and sodium aluminate, the template agent is one of n-butylamine, tetrapropylammonium bromide, triethanolamine, tetraethylammonium bromide and tetraethylammonium hydroxide, the alkali source is sodium hydroxide, and the silicon source is one of silica gel and silicon dioxide.

6. Use of the catalyst according to any one of claims 1 to 4 in the production of mesitylene from C9 mixed aromatic hydrocarbons through dealkylation and isomerization reactions.

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