CN106391114A

CN106391114A - Immobilized ionic liquid catalyst and application thereof

Info

Publication number: CN106391114A
Application number: CN201510468023.XA
Authority: CN
Inventors: 俞峰萍; 何文军; 宗弘元
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2015-08-03
Filing date: 2015-08-03
Publication date: 2017-02-15

Abstract

The invention relates to an immobilized ionic liquid catalyst and application thereof. The immobilized ionic liquid catalyst has a general structural formula as defined in the specification. In the general structural formula, P is a nanometer macroporous resin matrix; n is an integer in a range of 2 to 12; and M<-> is a negative ion selected from a group consisting of a trifluoromethanesulfonate group, a p-toluenesulfonate group, a benzenesulfonate group, a methanesulfonate group, a tetrafluoroborate group and a hexafluorophosphate group. The immobilized ionic liquid catalyst can be applied to industrial olefine acid addition for preparation of corresponding esters.

Description

Immobilized ionic liquid catalyst and application thereof

Technical Field

The invention relates to an immobilized ionic liquid catalyst and application thereof.

Background

Butyl acrylate is an important high molecular monomer and an organic intermediate, is a colorless transparent liquid at normal temperature, and has good chemical and physical properties such as weather resistance, water resistance, oil resistance, chemical resistance and the like. The industrial production methods of acrylic ester mainly include a nitrile ethanol method, an acrylonitrile hydrolysis method, an acrylic acid esterification method and an ester exchange method. Foreign basf, Rohm and Haas, Mitsubishi, Japan Bright petrochemical company, Ehlev and Ato chemistry, and the like, carry out scientific research and development on the crystal, and mainly focus on the improvement of the production process, including the multiphase azeotropic process. The development of new catalytic system includes heteropoly acid and its salt, solid super acid, macroporous zeolite system and ionic resin system.

The preparation of esters of olefins and lower carboxylic acids can be catalyzed by cation exchange resins containing sulfonic acid groups, as reported in U.S. Pat. Nos. 3678099, 2678332, 3031495, 3172905 and 3173943. One drawback of this process is the phenomenon of olefin polymerization that occurs during esterification, which results in a decrease in yield and the formation of by-products such as dimers that interfere with subsequent product separation, e.g., isobutylene dimer forms an azeotrope with butyl acetate, making product separation difficult.

Document US3644497 describes the use of an improved catalyst for the reaction of olefins containing unsaturation with carboxylic acids, the catalyst being a molybdenum or tungsten heteropoly acid catalyst. The temperature of the catalytic reaction is preferably 20-140 ℃ under the anhydrous condition, and the pressure is preferably 0-3000 PSIG; and the temperature and pressure under the water condition are slightly harsh, the temperature is preferably 50-175 ℃, and the pressure is preferably 0-4000 PSIG. The amount of water in the reaction system is varied according to the difference in the desired product. The molar ratio of water to olefin is 1 to 75, depending on the equilibrium of the alcohol and the corresponding ester.

The document US5384426 describes a process for preparing isopropyl acetate by esterification of propylene and acetic acid using an acidic resin as a catalyst. Propylene is derived from the by-product of isobutene production by petroleum cracking or isobutane dehydration. Reacting at the molar ratio of 0.5-1, the pressure of 15-50 kg/cm2 and the temperature of 70-120 ℃, and distilling to obtain the isobutyl acetate with the purity of 99.9%.

Document US6849759B1 describes a process for the production of organic esters, primarily a process for the production of ethyl acetate catalyzed by supported heteropolyacids or salts.

In recent years, the ionic liquid provides a wide space for people to search an environment-friendly catalytic system, has excellent chemical and thermodynamic stability, almost does not have vapor pressure at room temperature, and has the characteristics of convenient product separation and catalyst recovery when being applied to catalytic reaction. Gu et al (J.mol.Catal.A: chem., 2004, 212: 71-75) examined their catalytic activity in various olefin esterification reactions using sulfonic acid functionalized ionic liquids. The result shows that the catalyst can obtain good catalytic activity in most of olefins, and simultaneously, due to the characteristics of the ionic liquid, after the reaction is finished, the catalyst and the product can be separated only by pouring, and the ionic liquid can be reused after vacuum drying. Document CN1600773A describes a method for synthesizing ester by catalyzing olefin and organic acid with sulfonic acid functionalized ionic liquid as a catalyst, which uses an ionic liquid composed of alkyl pyridine or 1, 3-dialkyl imidazole cation with sulfonic acid group at the end and anion as a catalyst to catalyze the reaction of acetic acid and propylene at 50-150 ℃ under 0.1-2.0 MPa, wherein the acetic acid conversion rate is above 66%, and the selectivity reaches 100%. Although the catalytic efficiency of the catalyst is not reduced after 4 times of repeated use. However, the ionic liquid catalyst can be continuously used after being extracted and dried in vacuum.

Therefore, it is very important to research and develop an olefinic acid addition catalytic system with high activity, high selectivity and easy separation.

Disclosure of Invention

One of the objects of the present invention is to provide a novel supported ionic liquid catalyst. The second purpose of the invention is to provide the application of the immobilized ionic liquid catalyst. The immobilized ionic liquid catalyst has the characteristics of high catalytic activity, difficult inactivation and easy separation of reaction products when being used for addition of olefine acid.

In order to achieve one of the above purposes, the invention adopts the following technical scheme: an immobilized ionic liquid catalyst having the following general structural formula:

wherein,is a nano macroporous resin matrix; n is an integer from 2 to 12; m^-Is an anion selected from triflate, p-toluenesulfonate, benzenesulfonate, methanesulfonate, tetrafluoroborate or hexafluorophosphate.

In the above technical solution, preferably, n is an integer of 2 to 4.

In the above technical solution, preferably, M^-Is trifluoromethanesulfonate.

In the above technical scheme, preferably, the nano macroporous resin matrix is a nano macroporous copolymer obtained by in-situ copolymerization of a styrene monomer, a comonomer and a nano material. Wherein the styrene monomer is selected from at least one of styrene, alpha-methyl styrene or 4-butyl styrene. The comonomer is selected from at least one of ethylene glycol dimethacrylate, diacrylene, divinylphenylmethane or divinylbenzene. The nano material is at least one of multi-wall carbon nano tube, single-wall carbon nano tube, C60 or C70 fullerene. The pore-foaming agent is selected from at least one of aliphatic hydrocarbon, polystyrene, gasoline, fatty acid or paraffin.

In order to achieve the second purpose of the invention, the invention adopts the following technical scheme: the immobilized ionic liquid catalyst is used for catalyzing esterification reaction of olefin and organic acid.

In the above technical solution, preferably, the esterification reaction conditions are: the weight ratio of the immobilized ionic liquid catalyst to the reaction mixture is 0.001-0.1; the molar ratio of olefin to organic acid is 1: 5-5: 1; the reaction temperature is 60-150 ℃, and the reaction pressure is 0.5-3.0 MPa.

In the above technical solution, preferably, the olefin is carbon chain length C₂To C₁₈Linear, branched or cyclic olefins.

In the above technical solution, preferably, the organic acid is C₁To C₁₈Fatty acids or aromatic acids.

The preparation method of the immobilized ionic liquid catalyst comprises the following steps:

a) preparing an auxiliary agent into a water solution A with the weight percentage concentration of 0.5-2%, and preparing a styrene monomer, a comonomer, a nano material, an initiator and a pore-forming agent into a solution B; wherein,

the styrene monomer is selected from at least one of styrene, alpha-methyl styrene or 4-butyl styrene;

the comonomer is selected from at least one of ethylene glycol dimethacrylate, diacrylene, divinyl phenyl methane or divinyl benzene;

the nano material is selected from at least one of multi-wall carbon nano tubes, single-wall carbon nano tubes, C60 or C70 fullerene;

the initiator is selected from at least one of benzoyl peroxide, azobisisobutyronitrile, lauroyl peroxide or cumene hydroperoxide;

the auxiliary agent is selected from at least one of polyvinyl alcohol, gelatin, starch, methyl cellulose, bentonite or calcium carbonate;

the pore-foaming agent is selected from at least one of aliphatic hydrocarbon, polystyrene, gasoline, fatty acid or paraffin;

the weight portion of the styrene monomer is 85-95 parts, the comonomer is 2-5 parts, the nano material is 0.1-3 parts, and the initiator is 0.1-10 parts; the dosage of the auxiliary agent is 150-400% of the dosage of the monomer, and the dosage of the pore-foaming agent is 50-100% of the dosage of the monomer;

b) pre-polymerizing the solution B at 60-75 ℃ for 0.5-2.5 hours, then mixing the solution B with the solution A, heating to 70-90 ℃ for reaction for 5-15 hours, and heating to 90-100 ℃ for reaction for 5-15 hours; after the reaction is finished, extracting, washing, filtering, drying and sieving to obtain the composite macroporous microspheres with the particle size range of 0.35-0.60 mm;

c) chloromethylating the composite macroporous microspheres: adding a chloromethylation reagent which is 200-500% of the weight of the composite macroporous microspheres and a zinc chloride catalyst which is 20-70% of the weight of the composite macroporous microspheres into the composite macroporous microspheres, reacting for 8-30 hours at 30-60 ℃, filtering and washing to obtain composite macroporous chlorine spheres; the chloromethylation reagent is selected from at least one of chloromethyl ether, chloroethyl ether or 1, 4-dichloromethoxybutane;

d) reacting the mixture of the composite macroporous chlorine spheres, imidazole and acetonitrile at 60-90 ℃ to obtain composite imidazole microspheres; in the mixture, the molar ratio of the composite macroporous chlorine spheres to the imidazole to the acetonitrile is 1 (1-2) to 30-150;

e) mixing the composite imidazole microspheres with sultone reagents in an equimolar manner, and reacting at room temperature for 24-72 hours to obtain composite imidazole cationic microspheres; the sultone reagent is selected from at least one of 1, 4-butane sultone, 2, 4-butyl sultone and 1, 3-propane sultone;

f) mixing the composite imidazole cationic microspheres with organic sulfonic acid, and reacting at 25-60 ℃ for 1-5 hours to obtain the immobilized ionic liquid catalyst; wherein the molar ratio of the composite imidazole cationic microspheres to the organic sulfonic acid is (1:1) - (1: 2); the organic sulfonic acid is at least one of trifluoromethanesulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid or methanesulfonic acid.

The ionic liquid catalyst loaded by the nano macroporous resin is used in the addition reaction of olefine acid, the catalyst has high activity and selectivity, the product is easy to separate, and the catalyst can be continuously used for multiple times. The preferred scheme of the invention is that chloromethylated styrene, divinyl benzene and multi-walled carbon nano-tube in-situ copolymer resin matrix react with imidazole to form composite microspheres with imidazole groups, then the imidazole groups react with 1, 4-butyl sultone, and finally the composite microspheres react with trifluoromethanesulfonic acid to prepare the nano macroporous resin loaded ionic liquid catalyst. The nanometer macroporous resin loaded ionic liquid catalyst is used in the reaction of preparing sec-butyl acrylate by adding butene-1 and methacrylic acid, the catalyst has high activity, the conversion rate of the methacrylic acid can reach 94.1 percent, the selectivity of the sec-butyl methacrylate can reach 100 percent, the product is easy to separate, the catalyst is continuously used for 6 times, the activity is not obviously reduced, and the better technical effect is obtained.

The invention is further illustrated by the following examples.

Detailed Description

[ example 1 ]

58.0 g of styrene, 1.6 g of divinylbenzene, 30 g of polystyrene and 0.6 g of benzoyl peroxide initiator are added into a 500ml three-neck flask, and stirred and reacted for 2.0 hours at the temperature of 60 ℃; then 1.6 g of multi-walled carbon nanotubes were added and stirring was continued for 1 hour for prepolymerization. A solution of 2.5 g polyvinyl alcohol in 260ml of deionized water was added. Adjusting the stirring speed, gradually raising the temperature to 80 ℃ at the same time, and reacting for 5 hours; then the temperature is raised to 90 ℃ for reaction for 5 hours, and finally the temperature is raised to 98 ℃ for reaction for 6 hours. After the reaction is finished, pouring out the upper liquid, washing the upper liquid with hot water at 85 ℃ for several times, then washing the upper liquid with cold water for several times, then filtering the upper liquid, putting the upper liquid into an oven to dry the upper liquid at 80 ℃, sieving the upper liquid, and collecting the composite macroporous microspheres A with the particle size of 0.35-0.60 mm.

Chloromethylation of the composite macroporous microspheres: adding 50 g of composite macroporous microspheres A and 250ml of chloromethyl ether into a 500ml three-neck flask, standing at room temperature for 4 hours, starting stirring, adding 15 g of zinc chloride as a catalyst, heating to 50 ℃ for reacting for 18 hours, cooling to room temperature after chloromethylation is finished, filtering out a chlorination mother solution, repeatedly washing with methanol, and drying at 100 ℃ for 8 hours to obtain the composite macroporous chlorine spheres A.

30 g of composite macroporous chlorine ball A (the chlorine content is 1.5mmol Cl/g), imidazole (45.0mmol) and 220ml of acetonitrile are added into a 500ml three-necked bottle, the mixture reacts for 16 hours at 80 ℃, the mixture is cooled to room temperature and filtered, the mixture is washed by ethyl acetate, 0.1mol/L HCl, deionized water and methanol in sequence, and then the mixture is dried for 12 hours at 60 ℃ in vacuum to obtain the composite imidazole microsphere A.

Adding 30 g of composite imidazole microsphere A, 1, 4-butyl sultone with equimolar amount and 200ml of acetonitrile into a 250ml three-neck flask, stirring and refluxing at room temperature for 48 hours, pouring out upper-layer liquid after the reaction is finished, washing the microsphere for several times by using toluene, and then drying in vacuum for later use to obtain the composite imidazole cationic microsphere A.

Adding 30 g of composite imidazole cationic microsphere A, equimolar trifluoromethanesulfonic acid and acetonitrile into a 250ml three-neck flask, reacting for 2 hours at 40 ℃, pouring out the upper liquid after the reaction is finished, washing the microspheres for several times by toluene and diethyl ether respectively, and drying in vacuum to obtain the nano macroporous resin supported ionic liquid catalyst, namely Cat-A, wherein the structural formula of the catalyst is shown as

[ example 2 ]

A monomer mixture solution containing an initiator (60.0 g of styrene, 2.5 g of divinylbenzene, 60 g of polystyrene, 0.6 g of multi-walled carbon nano-tube and 1.0 g of benzoyl peroxide are added into a 500ml three-neck flask, the solution is stirred and reacted for 0.5 hour at the temperature of 70 ℃), a stirrer is started, a mixed solution of 200ml of deionized water and 5 g of gelatin is added, the temperature is raised to 85 ℃, the reaction is carried out for 3 hours, the temperature is raised to 90 ℃, the reaction is carried out for 9 hours, and finally the temperature is raised to 100 ℃, and the reaction is carried out for 10 hours. And after the reaction is finished, pouring out the upper liquid, washing with hot water at 85 ℃, washing with cold water, filtering, drying in an oven at 80 ℃, sieving, and collecting the composite macroporous microspheres B with the particle size of 0.35-0.60 mm.

Chloromethylation of the composite microspheres: adding 50 g of composite microsphere B and 200ml of chloroethyl ether into a 500ml three-neck flask, standing for 6 hours at room temperature, starting stirring, adding 30 g of zinc chloride as a catalyst, heating to 50 ℃ for reaction for 30 hours, cooling to room temperature after chloromethylation is finished, filtering out a chlorination mother solution, repeatedly washing with methanol, and drying for 8 hours at 100 ℃ to obtain the composite macroporous chlorine sphere B.

50 g of composite macroporous chlorine ball B (the chlorine content is 1.2mmol Cl/g), imidazole (60.0mmol) and 260ml of acetonitrile are added into a 500ml three-necked bottle, the mixture reacts for 16 hours at 80 ℃, the mixture is cooled to room temperature and filtered, the mixture is washed by ethyl acetate, 0.1mol/L HCl, deionized water and methanol in sequence, and then the mixture is dried for 12 hours at 60 ℃ in vacuum to obtain the composite imidazole microsphere B.

Adding 30 g of composite imidazole microsphere B, 1, 3-propane sultone with equimolar amount and 200ml of acetonitrile into a 250ml three-neck flask, stirring at room temperature, refluxing for reaction for 48 hours, pouring out upper-layer liquid after the reaction is finished, washing the microsphere for multiple times by using toluene, and then drying in vacuum for later use to obtain the composite imidazole cationic microsphere B.

Adding 30 g of composite imidazole cationic microsphere B, equimolar trifluoromethanesulfonic acid and acetonitrile into a 250ml three-neck flask, reacting for 2 hours at 40 ℃, pouring out the upper liquid after the reaction is finished, washing the microspheres for several times by toluene and diethyl ether respectively, and drying in vacuum to obtain the nano macroporous resin supported ionic liquid catalyst, namely Cat-B, wherein the structural formula of the catalyst is shown as

[ example 3 ]

Changing the anion (adopting p-toluenesulfonic acid, the dosage is equal to the mol of the compound imidazole cation microspheres A) in the [ example 1 ], and the rest preparation conditions are the same as the [ example 1 ], and finally obtaining Cat-C, wherein the structural formula is shown in the specification

[ example 4 ]

Changing the anion (adopting p-toluenesulfonic acid, the dosage is equal to the mol of the compound imidazole cation microspheres B) in the (example 2), and the other preparation conditions are the same as the (example 1), and finally obtaining Cat-D, wherein the structural formula is shown in the specification

[ example 5 ]

The prepared ionic liquid catalyst loaded by the nano macroporous resin is used for the reaction of C4 and methacrylic acid, and the conditions are as follows: 43.0 g of methacrylic acid and 5.0 g of ionic liquid catalyst Cat-A loaded by nano macroporous resin are added into a high-pressure reaction kettle, 140.0 g of 1-butene is filled, high-purity nitrogen is filled, the reaction pressure is maintained at 1.5MPa, the reaction temperature is 80 ℃, the catalyst is removed by filtration after the reaction is carried out for 3 hours, the conversion rate of the methacrylic acid is 94.1 percent, and the selectivity of the sec-butyl methacrylate is 100 percent.

[ examples 6 to 8 ]

The catalyst adopted in example 5 is changed, and Cat-B, Cat-C and Cat-D are used for replacing Cat-A to catalyze the addition esterification reaction of methacrylic acid and olefine acid of 1-butene. The reaction steps and conditions were the same as in [ example 5 ] except that the catalyst was changed, and analytical tests were performed after the reaction was completed, and the test results are shown in the following table.

Examples	Catalyst and process for preparing same	Conversion rate%	Selectivity%
				6	Cat-B	93.8	100
7	Cat-C	92.0	100
				8	Cat-D	90.6	100

[ examples 9 to 13 ]

The catalyst Cat-a in example 5 was separated from the reactant after the reaction was completed, washed several times with toluene and ether, and then dried in vacuum. Then, according to the reaction steps and reaction conditions in [ example 5 ], the olefine acid addition esterification reaction of methacrylic acid and 1-butene is catalyzed, and the result that the catalyst Cat-A is recycled for 2 times is obtained, which is shown in the following table. By analogy, the catalytic reactions with the cycle times of 3-6 times are respectively carried out, and the reaction results are shown in the following table.

Examples	Number of cycles	Conversion rate%	Selectivity%
				9	2	93.7	100
10	3	94.0	100
				11	4	93.8	100
12	5	93.5	100
				13	6	93.9	100

[ example 14 ]

60.0 g of acetic acid and 15.0 g of ionic liquid catalyst Cat-A loaded by nano macroporous resin are added into a high-pressure reaction kettle, 126.0 g of propylene is filled, high-purity nitrogen is filled, the reaction pressure is maintained at 1.5MPa, the reaction temperature is 120 ℃, the catalyst is removed by filtration after 3 hours of reaction, the conversion rate of the acetic acid is 94.3 percent, and the selectivity of the isopropyl acetate is 100 percent.

[ COMPARATIVE EXAMPLE 1 ]

Comparative example 1 was defined as a comparative example to example 14. The catalyst adopts trifluoromethanesulfonic acid 1-hexyl-3- (4-sulfonic acid group) butyl imidazole ionic liquid (the preparation method is shown in document CN1600773A), the dosage is 21.5 g, the catalyst with the dosage, 4.5 g of acetic acid and 9.45 g of propylene are added into a high-pressure reaction kettle, high-purity nitrogen is filled, the reaction pressure is maintained at 3.0MPa, the reaction temperature is 120 ℃, and sampling analysis is carried out after 4 hours of reaction, so that the conversion rate of the acetic acid is 85.5 percent, and the selectivity of the isopropyl acetate is 100 percent.

[ example 16 ]

The prepared ionic liquid catalyst Cat-A loaded by the nano macroporous resin is used for esterification addition reaction of different olefins and organic acid, and the conditions are as follows: sequentially adding a catalyst, olefin and carboxylic acid into a high-pressure reaction kettle, wherein the catalyst accounts for 1.5% of the mass of the reaction mixture; the molar ratio of olefin to carboxylic acid is 3: 1, then charging high-purity nitrogen, maintaining the reaction system in a liquid phase condition, reacting for 4 hours at 120 ℃, then cooling to room temperature, and sampling and analyzing. The results of the reaction analysis are shown in the following table.

Olefins	Carboxylic acids	Conversion rate%	Selectivity%
				2-methyl-2-butene	Acetic acid	98.7	100
1-octene	Acetic acid	95.8	100^a
				Cyclopentene	Acetic acid	93.5	100
Dicyclopentadiene	Acetic acid	94.0	100
				Propylene (PA)	Acetic acid	82.6	100
Propylene (PA)	Propionic acid	91.6	100
				Propylene (PA)	Acrylic acid	91.8	100
Propylene (PA)	Isooctanoic acid	85.8	100
				4-phenyl-1-butene	Phenylacetic acid	93.0	100

Note a: the product has three isomers, and the ratio is 5: 4: 1.

b: the reaction temperature is 50 ℃, the reaction time is 20 hours, and the molar ratio of olefine acid is 4: the reaction system takes toluene as a solvent.

Claims

1. An immobilized ionic liquid catalyst having the following general structural formula:

wherein,is a nano macroporous resin matrix; n is an integer from 2 to 12; m^-Is an anion selected from the group consisting of trifluoroMethanesulfonate, p-toluenesulfonate, benzenesulfonate, methanesulfonate, tetrafluoroborate or hexafluorophosphate.

2. The supported ionic liquid catalyst of claim 1, wherein n is an integer from 2 to 4; m^-Is trifluoromethanesulfonate.

3. The immobilized ionic liquid catalyst of claim 1, wherein the nano macroporous resin matrix is a nano macroporous copolymer obtained by in-situ copolymerization of a styrene monomer, a comonomer, a nanomaterial, and a porogen.

4. The supported ionic liquid catalyst of claim 3, wherein the styrenic monomer is selected from at least one of styrene, α -methylstyrene or 4-butylstyrene.

5. The supported ionic liquid catalyst of claim 3 wherein the comonomer is selected from at least one of ethylene glycol dimethacrylate, diacrylene, divinylphenylmethane or divinylbenzene.

6. The supported ionic liquid catalyst of claim 3, wherein the nanomaterial is selected from at least one of multi-walled carbon nanotubes, single-walled carbon nanotubes, C60, or C70 fullerenes.

7. The supported ionic liquid catalyst of claim 3, wherein the porogen is selected from at least one of aliphatic hydrocarbon, polystyrene, gasoline, fatty acid, and paraffin.

8. The use of the supported ionic liquid catalyst of claim 1 for catalyzing the esterification of an olefin and an organic acid.

9. Use of the supported ionic liquid catalyst according to claim 8, characterized in that the esterification reaction conditions are: the weight ratio of the immobilized ionic liquid catalyst to the reaction mixture is 0.001-0.1; the molar ratio of the olefin to the organic acid is (1:5) to (5: 1); the reaction temperature is 60-150 ℃, and the reaction pressure is 0.5-3.0 MPa.

10. Use of the supported ionic liquid catalyst of claim 8, wherein the olefin is of carbon chain length C₂To C₁₈Linear, branched or cyclic olefins; the organic acid is C₁To C₁₈Fatty acids or aromatic acids.