A process for the preparation of a heterogeneous catalyst, the catalyst and the use thereof

Abstract

A method for preparing a heterogeneous catalyst, characterized by comprising: treating MCM-41 molecular sieve with acid with a concentration of ≤1 mol / L, then mixing with silanization reagent and light aromatic hydrocarbon, stirring at 50-90 ℃ for 5-10 h, filtering and drying to obtain carrier MCM-41 molecular sieve, mixing the carrier MCM-41 molecular sieve, TiCl4 and toluene under anhydrous and anaerobic reaction conditions and nitrogen protection, stirring at 30-60 ℃ for 5-30 h, separating, washing and drying to obtain a heterogeneous catalyst composed of silanization-treated MCM-41 molecular sieve and titanium loaded thereon. The heterogeneous catalyst catalyzes the cyclotrimerization reaction of butadiene, and the reaction product contains less C16 or more products, and the selectivity of 1,5,9-cyclododecatriene is high.

Description

Technical Field

[0001] This disclosure relates to a method for preparing a butadiene cyclotrimerization catalyst and a method for catalyzing the cyclotrimerization of butadiene to 1,5,9-cyclododecanetriene. Background Technology

[0002] Butadiene is one of the three major olefins produced during petrochemical production and is an important organic chemical raw material with a wide range of applications. It is mainly used in the production of polybutadiene rubber, such as styrene-butadiene rubber, cis-butadiene rubber, nitrile rubber, and chloroprene rubber. With the rapid development of science and technology and the continuous advancement of low-molecular-weight olefin polymerization technology, such as dimerization and trimerization, it has received increasing attention. Among these, the most promising and industrially valuable products are the trimerization cyclization of butadiene to produce 1,5,9-cyclododecanetriene (CDT), and the dimerization cyclization to produce 1,5-cyclooctadiene (COD) and 4-vinylcyclohexene (VCH).

[0003] CDT is an important intermediate in the organic and fine chemical industries with special applications. It can be used to synthesize saturated or unsaturated diacids and their derivatives. It is also a raw material for polyesters, polyamides, plasticizers, flame retardants, macrocyclic organic compounds, and certain macrocyclic musk. The product of selective hydrogenation via an amine-rhodium catalyst can be used to produce nylon 12, cyclododecanoic acid, n-dodecane, bromododecane, cyclic dodecanoic acid-1 olefins, and cyclic dodecanoic acid-2 olefins, etc., demonstrating its wide range of industrial applications. Countries such as Germany began using cyclododecanoic acid-3 olefins as a raw material for the dodecanoic acid amine of nylon 12 in the 1970s.

[0004] COD and VCH also have a wide range of applications. COD and VCH react like typical olefins, such as selective hydrogenation, high-temperature and high-pressure complete hydrogenation, epoxidation, hydrogenation carboxylation and carbonylation, halogenation, etc. The main uses of COD are to produce nylon 8, octanoic acid, octenic acid, low-temperature plasticizers, monomers for polyamide fibers, engineering plastics, reactive diluents for epoxy resins, and third monomers for ethylene propylene rubber, etc. Halogenated COD and VCH have been used as flame retardants, and VCH is dehydrogenated to produce styrene.

[0005] The existing butadiene cyclization catalysts are mainly homogeneous catalysts, and the cyclotrimersation and cyclodimerization catalysts are different catalysts. The progress of the technology is embodied in improving the conversion rate of butadiene and the selectivity of CDT (or COD) under the homogeneous catalytic system. For example, US008168841 utilizes acetylacetone nickel or titanium halide / ethoxydiethyl aluminum or ethyl aluminum sesquichloride catalyst to prepare 1,5,9-cyclododecatriene from 1,3-butadiene trimerization. CN101070263A adopts titanium tetrachloride / half-ethyl aluminum chloride catalyst, and utilizes trace water, ammonia, amine, phenol or alcohol to adjust butadiene and benzene, 1,3-butadiene trimerization to prepare 1,5,9-cyclododecatriene. JP2005132770 utilizes I2TiCl2 / AlEt2Cl or BrITiCl2 / AlEt2Cl catalyst, adds trace water, and butadiene trimerization to prepare 1,5,9-cyclododecatriene. CN101970392A provides a method for preparing cyclododecatriene from 1,3-butadiene cyclotrimersation and a method for preparing lauryl lactone. DE1140562 and CN108002970A use Ni-A1-P system as catalyst to prepare COD from 1,3-butadiene cyclodimerization, and the yield can reach 96%. J Am Chem Soc, 1965: 87: 4652 first proposes that the iron complex catalytic system prepares COD from 1,3-butadiene cyclodimerization.

[0006] After the reaction of the homogeneous system is completed, the catalyst needs to be quenched and removed by adding polar substances such as water and alcohol, thereby introducing new impurities and causing problems such as non-recyclable catalyst and solid waste.

[0007] In order to solve the above problems, a heterogeneous catalyst is a better choice. JP2002060353 discloses a method for preparing butadiene by trimerizing butadiene in the presence of a catalyst containing a titanium compound and an organic aluminum compound, characterized in that 1 to 500 times by weight of a zeolite is added to the reaction system, and the catalytic activity and the selectivity of cyclododecatriene are improved. The zeolite is added as a third component, which is a solid aluminosilicate containing a Lewis base, and does not form a true heterogeneous catalyst with the active component. "Polymer-supported nickel catalyst for butadiene cyclotrimersation" (Journal of Nanjing College of Chemical Technology, Vol. 15 (1): 41) reports that an organic phosphine ligand is introduced into a polystyrene chain to prepare a zero-valent nickel supported catalyst, which mainly obtains CDT in the butadiene cyclotrimersation reaction.

[0008] MCM-41 is a kind of mesoporous material with highly ordered pore structure, the pore is hexagonal ordered arrangement, uniform size, the pore size can be continuously adjusted in the range of 2-10 nm, and the specific surface area is large. SUMMARY

[0009] The inventors of the present application find that mesoporous molecular sieve MCM-41 is modified and then loaded with titanium compounds to prepare a heterogeneous catalyst, and the catalyst is used to catalyze 1,3-butadiene cyclization polymerization with aluminum alkyl chloride as a cocatalyst, and the product has less by-products of C16 and above. The solid catalyst can be recovered by simple filtration or centrifugal treatment, and recycled for reaction, and the selectivity of the product CDT and C16 has no obvious change. Based on this, the present application is formed.

[0010] The present application aims to provide a heterogeneous catalyst different from the prior art, and a preparation method and application thereof.

[0011] To achieve the above-mentioned purpose, the first aspect of the present application provides a method for preparing a butadiene cyclization trimerization catalyst, characterized in that the method comprises: treating MCM-41 molecular sieve with an acid with a concentration of ≤1 mol / L, then mixing the treated MCM-41 molecular sieve with a silylating agent and light aromatic hydrocarbon, stirring at 50-90 ℃ for 5-10 h, filtering and drying to obtain a carrier MCM-41 molecular sieve, mixing the carrier MCM-41 molecular sieve, TiCl4 and toluene under anhydrous and anaerobic reaction conditions and nitrogen protection, stirring at 30-60 ℃ for 5-30 h, and separating, washing and drying to obtain a heterogeneous catalyst composed of a silylated MCM-41 molecular sieve and titanium loaded thereon; wherein the silylating agent has a general formula of R''R'N-(CH2)n-Si-A'A''A''', R' and R'' are both H or one of R' and R'' is H and the other is a C1-C4 alkyl group, A', A'' and A''' are all methoxy groups or all ethoxy groups, or when any one of A', A'' and A''' is a methyl group or an ethyl group, the other two are all methoxy groups, all ethoxy groups or methoxy and ethoxy groups respectively, and n is 1, 2, 3 or 4; the weight ratio of the MCM-41 molecular sieve, the silylating agent and the light aromatic hydrocarbon is 1:0.3-1.5:1-5, the weight ratio of TiCl4 to the carrier MCM-41 molecular sieve is 0.3-1.2, and the weight ratio of toluene to the carrier SBA-15 molecular sieve is 5-15:1.

[0012] Optionally, the acid is nitric acid.

[0013] In the general formula of the silylating agent, preferably, R' and R'' are both H.

[0014] Preferably, the silylating agent is 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane or N-methyl-3-aminopropyltrimethoxysilane.

[0015] The light aromatic hydrocarbon can be selected from benzene, toluene, ethylbenzene, xylene and the like, and preferably, the light aromatic hydrocarbon is toluene.

[0016] The weight ratio of TiCl4 to the support MCM-41 molecular sieve is preferably 0.5-0.9.

[0017] To achieve the above-mentioned purpose, the second aspect of the present application provides a heterogeneous catalyst, which is characterized by being composed of a silanized MCM-41 molecular sieve and titanium supported thereon, and the titanium content is 0.5-15% by mass of the catalyst, preferably, the titanium content is 5-10%.

[0018] To achieve the above-mentioned purpose, the third aspect of the present application provides a method for cyclotrimerization of butadiene, which is characterized by using 1,3-butadiene as a raw material, and the reaction is carried out at 30-90℃ in the presence of a heterogeneous catalyst composed of a silanized MCM-41 molecular sieve and titanium supported thereon, and an alkyl aluminum chloride as a cocatalyst, to obtain 1,5,9-cyclododecatriene.

[0019] Preferably, the alkyl aluminum chloride is diethylaluminum chloride or diethylaluminum sesquichloride.

[0020] Preferably, the molar ratio of the cocatalyst to the heterogeneous catalyst is 5-40, and the heterogeneous catalyst is calculated based on titanium.

[0021] The present application uses a silanized MCM-41 mesoporous molecular sieve and a titanium compound to prepare a heterogeneous catalyst, which, together with an alkyl aluminum chloride cocatalyst, catalyzes the cyclotrimerization of 1,3-butadiene, and the reaction product contains less C16 and above products and has high CDT selectivity. In addition, the present application overcomes the drawbacks of the prior art, such as the need to add water, alcohol and other polar substances to quench and remove the catalyst after the reaction is completed, which introduces new impurities and makes the catalyst non-recyclable and generates solid waste. The heterogeneous solid catalyst provided by the present application can be recycled by simple filtration or centrifugation, and the selectivity of CDT and C16 does not change significantly, thereby reducing solid waste. DETAILED DESCRIPTION

[0022] The present application is further described below by way of examples, but is not limited thereto.

[0023] Examples 1-4 are used to illustrate the heterogeneous catalyst and the preparation method thereof provided by the present application.

[0024] Example 1

[0025] a. Under stirring, 30g of MCM-41 molecular sieve (produced by Sinopec Jianshang Petrochemical Co., Ltd., full-silicon molecular sieve, specific surface area 810m 2 / g, pore volume 0.794cm 3g) mixed with 600 g of 1 mol / L nitric acid solution, reacted at reflux temperature for 1 h, filtered, washed with deionized water until neutral, dried at 120 °C, pretreated MCM-41 molecular sieve;

[0026] b) 18 g of pretreated MCM-41 molecular sieve, 18 g of 3- aminopropyltrimethoxysilane H2N(CH2)3Si(OCH3)3 and 54 g of toluene were mixed, stirred at 60 °C for 10 h, the solid was filtered and dried at 120 °C to obtain the support MCM-41 molecular sieve;

[0027] c) 26 g of support MCM-41 molecular sieve, 19 g of TiCl4 and 260 g of toluene were mixed under anhydrous and anaerobic reaction conditions, stirred at 30 °C for 30 h under nitrogen protection, filtered, washed with hexane three times, and dried to obtain the heterogeneous catalyst HeM1, wherein the titanium content was 9.8%.

[0028] Example 2

[0029] a) the same as example 1;

[0030] b) 22 g of pretreated MCM-41 molecular sieve, 22 g of 3- aminopropyltriethoxysilane H2N(CH2)3Si(OC2H5)3 and 66 g of toluene were mixed, stirred at 70 °C for 7 h, the solid was filtered and dried at 120 °C to obtain the support MCM-41 molecular sieve.

[0031] c) 30 g of support MCM-41 molecular sieve, 19 g of TiCl4 and 300 g of toluene were mixed under anhydrous and anaerobic reaction conditions, stirred at 40 °C for 20 h under nitrogen protection, filtered, washed with hexane three times, and dried to obtain the heterogeneous catalyst HeM2, wherein the titanium content was 8.6%.

[0032] Example 3

[0033] a) the same as example 1;

[0034] b) 19 g of pretreated MCM-41 molecular sieve, 19 g of 3- aminopropylmethyldiethoxysilane H2N(CH2)3Si(CH2)(OC2H5)2 and 57 g of toluene were mixed, stirred at 80 °C for 6 h, the solid was filtered and dried at 120 °C to obtain the support MCM-41 molecular sieve.

[0035] c) 29 g of support MCM-41 molecular sieve, 26 g of TiCl4 and 290 g of toluene were mixed under anhydrous and anaerobic reaction conditions, stirred at 50 °C for 10 h under nitrogen protection, filtered, washed with hexane three times, and dried to obtain the heterogeneous catalyst HeM3, wherein the titanium content was 7.2%.

[0036] Example 4

[0037] a. Same as Example 1;

[0038] b. 19 g of pretreated MCM-41 molecular sieve, 19 g of N-methyl-3- aminopropyltrimethoxysilane CH3NH(CH2)3Si(OCH3)3 and 57 g of toluene were mixed, stirred at 90 °C for 5 h, and the solid was filtered and dried at 120 °C to obtain the support MCM-41 molecular sieve.

[0039] c. 29 g of the support MCM-41 molecular sieve, 18 g of TiCl4 and 290 g of toluene were mixed under anhydrous and anaerobic conditions under nitrogen protection, stirred at 60 °C for 5 h, filtered, washed with hexane for 3 times, and dried to obtain the heterogeneous catalyst HeM4, wherein the titanium content was 6.2%.

[0040] Example 5

[0041] 1L Parr reactor was replaced with nitrogen for 3 times, 300 mL of toluene, 12.4 g (50 mmol) of hemiethyl aluminum chloride and 1.9 g (4 mmol of titanium) of the heterogeneous catalyst HeM1 were added into the reactor under nitrogen protection, stirring was started, 1,3-butadiene was continuously introduced, the temperature was kept at 53 °C, and the pressure was kept at 0.1 MPa, and the reaction was carried out for 2 hours. After the reaction was completed, the reaction mixture was filtered under nitrogen protection, the obtained solid was recorded as Re-HeM1, and was stored under nitrogen protection, and the obtained liquid was added with methanol to terminate the reaction, and the reaction product was distilled under reduced pressure at a pressure of 2.7 kPa, the fraction collected at 40-50 °C was C8, the fraction collected at 110-117 °C was 1,5,9-CDT, and the rest was C16 or more products. The selectivity of 1,5,9-CDT, C8 and C16 or more products was 92.3%, 5.3% and 2.4%, respectively.

[0042] Re-HeM1 was filtered under nitrogen protection, washed with hexane for 3 times, and dried. The above-mentioned cyclotrimerization of 1,3-butadiene was carried out again using Re-HeM1 instead of HeM1. The selectivity of 1,5,9-CDT, C8 and C16 or more products was 91.8%, 5.6% and 2.6%, respectively.

[0043] Example 6

[0044] This example illustrates the method for cyclotrimerization of butadiene provided by the application.

[0045] The same as Example 5, except that HeM2 was used instead of HeM1.

[0046] The selectivity of 1,5,9-CDT, C8 and C16 or more products was 93.6%, 4.4% and 2%, respectively.

[0047] Re-HeM2 was filtered under nitrogen protection, washed with hexane for 3 times, and dried. Then, the above-mentioned cyclotrimerization of 1,3-butadiene was carried out again by using Re-HeM2 instead of HeM2. The selectivity of 1,5,9-CDT, C8 and C16 was 93.2%, 4.6% and 2.2%, respectively.

[0048] Example 7

[0049] This example illustrates the method for cyclotrimerization of butadiene provided by the present application.

[0050] The same as Example 5, except that HeM3 was used instead of HeMl.

[0051] The selectivity of 1,5,9-CDT, C8 and C16 was 92.6%, 5.6% and 1.8%, respectively.

[0052] Re-HeM3 was filtered under nitrogen protection, washed with hexane for 3 times, and dried. Then, the above-mentioned cyclotrimerization of 1,3-butadiene was carried out again by using Re-HeM3 instead of HeM3. The selectivity of 1,5,9-CDT, C8 and C16 was 92.9%, 5.2% and 1.9%, respectively.

[0053] Example 8

[0054] This example illustrates the method for cyclotrimerization of butadiene provided by the present application.

[0055] The same as Example 5, except that HeM4 was used instead of HeMl.

[0056] The selectivity of 1,5,9-CDT, C8 and C16 was 95.2%, 3.7% and 1.1%, respectively.

[0057] Re-HeM4 was filtered under nitrogen protection, washed with hexane for 3 times, and dried. Then, the above-mentioned cyclotrimerization of 1,3-butadiene was carried out again by using Re-HeM4 instead of HeM4. The selectivity of 1,5,9-CDT, C8 and C16 was 94.7%, 3.8% and 1.5%, respectively.

[0058] Example 9

[0059] This example illustrates the method for cyclotrimerization of butadiene provided by the present application.

[0060] The same as Example 5, except that the ratio of promoter and heterogeneous catalyst was changed to 30:1.

[0061] The selectivity of 1,5,9-CDT, C8 and C16 was 93.6%, 3.5% and 2.9%, respectively.

[0062] Example 10

[0063] This example illustrates the method for cyclotrimerization of butadiene provided by the present application.

[0064] The same as Example 5, except that the co-catalyst was replaced by diethylaluminum chloride.

[0065] The selectivity of 1,5,9-CDT, C8 and C16 above products were 92.7%, 4.1% and 3.2%, respectively.

[0066] Example 11

[0067] This example illustrates the method for cyclotrimerization of butadiene provided by the present application.

[0068] The same as Example 5, except that the cyclotrimerization reaction temperature was changed to 77°C.

[0069] The selectivity of 1,5,9-CDT, C8 and C16 above products were 90%, 5.2% and 4.8%, respectively.

Claims

1. A method for butadiene cyclization trimerization, wherein 1,3-butadiene is used as a raw material, and the reaction occurs at 30-90°C in the presence of a heterogeneous catalyst and alkyl aluminum chloride as a co-catalyst to obtain 1,5,9-cyclododecanetriene; characterized in that... The heterogeneous catalyst is prepared by the following method: MCM-41 molecular sieve is treated with nitric acid of concentration ≤1 mol / L, then mixed with a silanizing agent and light aromatic hydrocarbons, and reacted with stirring at 50-90℃ for 5-10 h. After filtration and drying, the supported MCM-41 molecular sieve is obtained. Under anhydrous and oxygen-free reaction conditions and nitrogen protection, the supported MCM-41 molecular sieve, TiCl4, and toluene are mixed and reacted with stirring at 30-60℃ for 5-30 h. After separation, washing, and drying, a heterogeneous catalyst consisting of silanized MCM-41 molecular sieve and titanium supported thereon is obtained; wherein, the MCM-41 molecular sieve is an all-silica molecular sieve, and the silanizing agent has the general formula R. ″ R ′ N-(CH2)n-Si-A ′ A ″ A ″′ The R ′ and the R mentioned above ″ Simultaneously H or the aforementioned R ′ and the R ″ One of them is H and the other is a C1-C4 alkyl group, wherein A ′ A ″ A ″′ All are methoxy or all are ethoxy, or, when said A ′ A ″ A ″′ When any one of them is methyl or ethyl, the other two are either methoxy, either are either ethoxy, or either are methoxy or ethoxy respectively, and n is 1, 2, 3 or 4.

2. The method according to claim 1, characterized in that, In the general formula of the silanizing agent, R ′ and R ″ It is also H.

3. The method according to claim 1, characterized in that, The silanizing agent is 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, or N-methyl-3-aminopropyltrimethoxysilane.

4. The method according to claim 1, characterized in that, The weight ratio of the MCM-41 molecular sieve, silanizing agent, and light aromatic hydrocarbon is 1:0.5-1.5:1-5.

5. The method according to claim 1, characterized in that, The light aromatic hydrocarbon is toluene.

6. The method according to claim 1, characterized in that, The weight ratio of TiCl4 to the support MCM-41 molecular sieve is 0.3-1.

2.

7. The method according to claim 1, characterized in that, The weight ratio of TiCl4 to the support MCM-41 molecular sieve is 0.5-0.

9.

8. The method according to claim 1, characterized in that, The weight ratio of toluene to the carrier MCM-41 molecular sieve is 5-15:

1.

9. The method according to claim 1, characterized in that, The titanium content in the heterogeneous catalyst is 0.5-15% by mass.

10. The method according to claim 9, characterized in that, The titanium content is 5-10%.

11. The method according to claim 1, characterized in that, The alkyl aluminum chloride is sesquiethyl aluminum chloride or diethylaluminum chloride.

12. The method according to claim 1, characterized in that, The molar ratio of the co-catalyst to the heterogeneous catalyst is 5-40, and the heterogeneous catalyst is calculated as titanium.