阅读说明：本技术 一种非金属酸性功能化复配离子液体催化丁烯可控聚合的方法 (Method for catalyzing controllable polymerization of butylene by using non-metallic acidic functional compound ionic liquid ) 是由 王慧 陈健 王红岩 李增喜 张锁江 于 2020-12-14 设计创作，主要内容包括：本发明涉及一种非金属酸性功能化复配离子液体催化丁烯可控聚合的方法,催化剂以季铵离子液体为主催化剂,酸性可调的离子液体或可强化反应体系传质的离子液体为助剂。该方法具有以下优势：1.催化剂不易挥发、环境友好、反应条件温和、催化活性高,产物易与催化剂分离,且无催化剂残留。2.相比纯离子液体催化剂,复配催化体系的酸强度调节范围更广,反应体系界面传质得到极大改善,具有更优异的催化性能,且可通过改变主催化剂和助剂的配比调控产物中二聚体、三聚体、四聚体的分布。(The invention relates to a method for catalyzing controllable polymerization of butylene by using non-metallic acidic functional compound ionic liquid. The method has the following advantages: 1. the catalyst is not easy to volatilize, environment-friendly, mild in reaction condition, high in catalytic activity, easy to separate a product from the catalyst, and free of catalyst residue. 2. Compared with a pure ionic liquid catalyst, the acid strength of the compound catalytic system is wider in adjustment range, the interface mass transfer of the reaction system is greatly improved, the catalyst has more excellent catalytic performance, and the distribution of dimers, trimers and tetramers in the product can be regulated and controlled by changing the proportion of the main catalyst and the auxiliary agent.)

1. A method for catalyzing controllable polymerization of butylene by using non-metallic acidic functional compound ionic liquid is characterized in that an acidic adjustable ionic liquid compound system and an ionic liquid compound system capable of strengthening mass transfer of a reaction system are constructed by using quaternary ammonium ionic liquid as a main catalyst, and the reaction process comprises the following steps: adding the ionic liquid catalyst and the butylene into a reactor, raising the temperature for reaction, naturally separating the product from the catalyst to realize separation after the reaction is finished, and recovering the catalyst.

2. The built ionic liquid catalytic system of claim 1, wherein the main catalyst is sulfotriethylammonium trifluoromethanesulfonic acid.

3. The built ionic liquid catalytic system of claim 1, wherein the acidic adjustable ionic liquid complex system is a combination of a main catalyst and an acidic functionalized ionic liquid auxiliary agent, and the mass transfer enhancement ionic liquid built system is a combination of a main catalyst and a long alkyl chain functionalized ionic liquid auxiliary agent with higher olefin solubility.

4. The functionalized ionic liquid assistant according to claim 3, wherein the ionic liquid functionalized group is one or two of an acidic functionalized group and a long alkyl chain functionalized group, the acidic functionalized group is one of sulfopropyl and sulfobutyl, and the long alkyl chain functionalized group is a straight-chain alkyl group with four to sixteen carbon atoms.

5. The functionalized ionic liquid assistant according to claim 3, wherein the acidic functionalized ionic liquid cation is one or a combination of more than one of sulfotriethylammonium, sulfopyridine and sulfomethylimidazole, the long-alkyl-chain functionalized ionic liquid cation is one or a combination of more than one of long-alkyl-chain triethylammonium, long-alkyl-chain pyridine and long-alkyl-chain methylimidazole, and the anion of the ionic liquid assistant is one or a combination of more than one of trifluoromethanesulfonic acid, p-toluenesulfonate, perchlorate, methanesulfonate, bisulfate and hexafluoroisopropylsulfonate.

6. The compound ionic liquid catalytic system of claim 2, wherein the compound molar ratio of the main catalyst to the auxiliary agent is 10:1-1: 5.

7. The method for the controlled polymerization of the compound ionic liquid catalyzed butene according to claim 1, wherein the raw material butene is one or more of 1-butene and isobutene, the reaction is carried out in a reaction kettle with mechanical stirring under the reaction condition of N₂Protecting, wherein the mol ratio of the butylene raw material to the catalyst is 5:1-20:1, the reaction time is 1-12h, the reaction temperature is 40-120 ℃, the reaction pressure is 1.6-5MPa, and the stirring speed is 500-.

The technical field is as follows:

the invention belongs to the field of industrial catalysis, and relates to a method for catalyzing controllable polymerization of butylene by using a non-metallic acidic functional compound ionic liquid.

Background art:

the alkylate oil taking isooctane as a main component is one of ideal gasoline blending components and is an ideal choice for replacing the MTBE which is an environmental pollution additive at present. Compared with the direct alkylation process of isobutane/butylene, the alkylate obtained by the indirect alkylation method of hydrogenation after butylene oligomerization is superior in quality in the synthetic route of alkylate, and can be realized on the basis of the transformation of an MTBE (methyl tert-butyl ether) production device, and meanwhile, the butylene raw material can be fully utilized. In the indirect alkylation process, the hydrogenation technology is mature, the controllable polymerization of the butene is a key step, and the development of the high-efficiency catalyst is the core of the controllable polymerization process of the butene.

In the catalyst for polymerizing butene, the traditional liquid acid such as sulfuric acid and methanesulfonic acid catalyzes polymerization reaction and has the problems of environmental pollution and poor product selectivity; the solid phosphoric acid is used for catalyzing the dimerization of the low-carbon olefin, so that the reaction temperature can be obviously reduced, the excellent catalytic performance is shown, and the problems of easy inactivation and difficult regeneration exist; the transition metal complex catalyst has higher activity of catalyzing the polymerization of low-carbon olefin, but the effective amount of the catalyst is quite low, the synthesis steps are complex and the synthesis process is uncontrollable. The ionic liquid is used as a non-conventional medium with designable structure and property, and provides a new idea for solving the problems of the traditional catalyst. The ionic liquid has excellent dissolving performance, a flexibly designed variable structure, negligible vapor pressure keeps the stability of a catalytic environment, and strong association acting force among the ionic liquids also ensures the stability and the cyclicity of the ionic liquid. Reported to contain AlCl₃And FeCl₃The metal-based ionic liquid shows excellent catalytic performance and recycling performance of butene polymerization, but the ionic liquid is relatively serious in equipment corrosion, relatively sensitive to water and air, easy to decompose, and easy to leave halogen in products.

The non-metal ionic liquid catalyst can efficiently catalyze olefin polymerization, and can make up the defects, and the patent develops a non-metal ionic liquid catalytic system with dual functions of solvent and catalysis so as to realize the controllable polymerization of olefin.

The invention content is as follows:

aiming at the problems existing in the existing catalytic system for polymerizing the butylene, the invention aims to provide an acidic non-metal ionic liquid catalyst for realizing the controllable polymerization of the butylene. The nonmetal ionic liquid system developed by the invention can overcome the problems of unstable performance, difficult regeneration, difficult separation of the catalyst and products, uncontrollable product distribution and the like of the traditional catalyst.

The invention provides a method for catalyzing controllable polymerization of butylene by using a non-metal functional compound ionic liquid. The preparation of the catalyst comprises the following steps:

(1) the functionalized ionic liquid auxiliary agent is mainly synthesized by a two-step method: firstly, introducing one of an acidic group and a long alkyl chain functional group into one of organic substrates of imidazole, pyridine or triethylamine to form zwitterions (halogenated ionic liquid), and washing and purifying by one or a combination of organic solvents of toluene and diethyl ether;

(2) then, carrying out protonation (or ion exchange) reaction on zwitterion (or halogenated ionic liquid) and corresponding acid (or salt) to generate a target ionic liquid auxiliary agent, and washing and purifying by one or a mixed system of organic solvents of toluene and diethyl ether;

(3) the prepared quaternary ammonium ionic liquid main catalyst and an acidic or long alkyl chain functionalized ionic liquid auxiliary agent are uniformly mixed according to a certain proportion, and a compound ionic liquid catalyst is generated by strong association force. The introduction of the functional group in the step (1) is completed through protonation reaction and grafted to the nitrogen atom active site of the organic substrate through interaction reaction. The product is one of ionic liquid or amphoteric intermediate. The reaction condition is inert protection atmosphere, the reaction time is 4-24h, the reaction temperature is 40-80 ℃, the stirring speed is 50-200r/min, and the reaction product is washed and purified for 2-4 times by organic solvent, and dried in vacuum for 12-24h to remove water.

And (3) finishing the introduction of the anions in the step (2) through a protonation reaction or an ion exchange reaction, and reacting the zwitterion intermediate or the halogenated ionic liquid obtained in the step (1) with the acid (or salt) corresponding to the target anions to replace the anions with the target anions. Synthesizing the ionic liquid in an inert protective atmosphere, reacting for 4-24h at 40-80 ℃, stirring at a speed of 50-200r/min, washing and purifying for 2-4 times by using an organic solvent, and drying in vacuum to remove water for 12-24 h.

And (3) compounding sulfonic triethylammonium trifluoromethanesulfonic acid with catalytic activity and an ionic liquid auxiliary agent without catalytic activity, wherein an acidic adjustable compound ionic liquid catalyst is a compound of a main catalyst and an acidic ionic liquid auxiliary agent, and the mass transfer compound ionic liquid catalyst can be enhanced to be a compound of the main catalyst and the ionic liquid auxiliary agent containing a long alkyl chain. The compounding process is carried out in an inert protective atmosphere, the compounding molar ratio of the main catalyst to the auxiliary agent is 10:1-1:5, the mixing time is 4-6h, the mixing temperature is 40-60 ℃, and the stirring speed is 50-200 r/min.

The controllable polymerization process of the compound ionic liquid for catalyzing butylene mainly comprises the following steps:

(1) adding an ionic liquid catalyst into the reaction kettle, and replacing air in the reaction kettle with high-purity nitrogen. The reactor is pressurized to a certain pressure while being heated to a set temperature.

(2) Pumping the olefin into the reaction kettle by a metering pump, stirring and mixing the ionic liquid and the raw material in the reaction kettle, and controlling the stirring speed at 500-1500 r/min.

(3) The reaction is carried out for a certain time at a specific temperature, the stirring is stopped immediately after the reaction is finished, and the ionic liquid is separated from the polymerization product. And taking out the upper oil phase, and washing to obtain a final product.

Compared with the prior art, the invention has the following effects:

the compound acidic ionic liquid adjusts the acid strength of the catalyst, the butene solubility and the mass transfer rate of a reaction interface through the proportion of the ionic liquid containing different functional groups, thereby effectively adjusting and controlling the distribution and the reaction rate of each component in the product. Compared with the existing solid acid catalyst, the composite acidic ionic liquid catalyst has stable catalytic performance, simple and easy regeneration steps, and no problems of easy inactivation and difficult regeneration.

The specific implementation mode is as follows:

in order to make the objects, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below with reference to examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Comparative example 1

Adding 10mmol of a pure ionic liquid catalyst sulfonic triethyl ammonium trifluoromethanesulfonic acid into a 100mL high-pressure reaction kettle, replacing air in the reaction kettle with high-purity nitrogen, and pressurizing the reactor to 2 MPa. 10mL of isobutylene was pumped into the reaction kettle by a metering pump. The ionic liquid and the raw materials are stirred and mixed in a reaction kettle, and the stirring speed is controlled at 1000 r/min. Controlling the reaction temperature at 100 ℃, cooling to room temperature after reaction time of 1h, and separating the ionic liquid from the reaction product. Taking out the upper oil phase, and washing to obtain the final oil product. According to gas chromatography analysis, the isobutene conversion under these conditions was 25.5% by weight and the dimer content in the product was 57.2% by weight. (unified reaction conditions of pure ionic liquid catalyst)

Example 1

Adding a compound ionic liquid catalyst into a 100mL high-pressure reaction kettle: 10mmol of sulfotriethylammonium trifluoromethanesulfonate and 5mmol of sulfotriethylammonium hydrogen sulfate, replacing air in the reaction kettle with high-purity nitrogen, and pressurizing the reactor to 2 MPa. 10mL of isobutylene was pumped into the reaction kettle by a metering pump. The ionic liquid and the raw materials are stirred and mixed in a reaction kettle, and the stirring speed is controlled at 1000 r/min. Controlling the reaction temperature at 100 ℃, cooling to room temperature after reaction time of 1h, and separating the ionic liquid from the product phase. And taking out the upper oil phase, and washing to obtain a final product. Under these conditions, the conversion of isobutene was 47.4% by weight and the proportion of dimer in the product was 79.1% by weight. (optimum working condition for selectivity adjustment of acidity adjustable compound ionic liquid catalyst)

Example 2

Adding a compound ionic liquid catalyst into a 100mL high-pressure reaction kettle: 10mmol of sulfotriethylammonium trifluoromethanesulfonate and 5mmol of sulfomethylimidazole dihydrogen phosphate, replacing air in the reaction kettle with high-purity nitrogen, and pressurizing the reactor to 2 MPa. 10mL of isobutylene was pumped into the reaction kettle by a metering pump. The ionic liquid and the raw materials are stirred and mixed in a reaction kettle, and the stirring speed is controlled at 1000 r/min. Controlling the reaction temperature at 100 ℃, cooling to room temperature after reaction time of 1h, and separating the ionic liquid from the product. Taking out the upper oil phase, and washing to obtain the final oil product. Under these conditions, the conversion of isobutene was 15.6% by weight and the proportion of dimer in the product was 90.2% by weight. (worst condition of selectivity adjustment of acid adjustable compound ionic liquid catalyst)

Example 3

Adding a compound ionic liquid catalyst into a 100mL high-pressure reaction kettle: 10mmol of sulfotriethyl ammonium trifluoromethanesulfonate and 5mmol of dodecyl pyridine perchlorate, replacing air in a reaction kettle with high-purity nitrogen, and pressurizing the reactor to 2 MPa. 10mL of isobutylene was pumped into the reaction kettle by a metering pump. The ionic liquid and the raw materials are stirred and mixed in a reaction kettle, and the stirring speed is controlled at 1000 r/min. Controlling the reaction temperature at 100 ℃, cooling to room temperature after reaction time of 1h, and separating the ionic liquid from the product. Taking out the upper oil phase, and washing to obtain the final oil product. Under these conditions, the conversion of isobutene was 85.8% by weight and the proportion of dimer in the product was 58.8% by weight. (optimum working conditions for improved conversion of Mass transfer enhanced Complex Ionic liquid catalyst)

Example 4

As in comparative example 1, the reaction temperature was controlled to 40 ℃ under which the conversion of isobutylene was 18.81% by weight and the dimer was 85.2% by weight in the product. (optimum working Condition for Selectivity of pure Ionic liquid catalyst)

Example 5

As in comparative example 1, the total amount of ionic liquid was controlled to be 5mmol, under which the conversion of isobutylene was 14.4% by weight and the dimer content in the product was 65.6% by weight. (worst case of pure Ionic liquid catalyst)

Example 6

In the same way as in comparative example 1, the total amount of the compound ionic liquid is controlled to be 20mmol, under the condition, the conversion rate of isobutene is 75.5 wt%, and the proportion of the dimer in the product is 45.7 wt%. (optimum working conditions for conversion of pure ionic liquid catalyst)

Example 7

As in comparative example 1, the reaction time was controlled to 4 hours, under which conditions the isobutene conversion was 76.1% by weight and the dimer content in the product was 55.6% by weight. (optimum operating mode for conversion under the influence of reaction time of pure ionic liquid catalyst)

Example 8

As in comparative example 1, the starting material isobutylene was controlled to be 1-butene, under which the conversion of isobutylene was 22.1% by weight, and the dimer was 34.7% by weight in the product. (other raw material conditions of pure ionic liquid catalyst)

The applicant states that the present invention is illustrated in detail by the above examples, but the present invention is not limited to the above examples, i.e. it is not meant that the present invention must rely on the above detailed methods for its implementation. It should be understood by those skilled in the relevant art that any modification of the present invention, equivalent replacement of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope of protection and disclosure of the present invention.