阅读说明：本技术 草酸酯脱羰制备碳酸酯的方法 (Method for preparing carbonic ester by decarbonylation of oxalate ) 是由 陈梁锋 朱俊华 唐康健 程远琳 王黎敏 于 2018-08-21 设计创作，主要内容包括：本发明涉及一种草酸酯脱羰制备碳酸酯的方法,主要解决现有技术中反应条件苛刻、催化剂活性低、容易失活的问题。所述方法包括草酸酯与催化剂接触制备碳酸酯的步骤；所述催化剂以重量份数计,包括50～90份的聚苯乙烯树脂和10～50份的季鏻盐PR<Sub>1</Sub>R<Sub>2</Sub>R<Sub>3</Sub>X,基于所述聚苯乙烯树脂和所述季鏻盐的总重量份数；其中,R<Sub>1</Sub>、R<Sub>2</Sub>和R<Sub>3</Sub>分别为芳基或烷基C<Sub>a</Sub>H<Sub>b</Sub>,a＝2～10,b＝4～20；X为F、Cl、Br或I。(The invention relates to a method for preparing carbonic ester by decarbonylation of oxalate, which mainly solves the problems of harsh reaction conditions, low catalyst activity and easy inactivation in the prior art. The method comprises the steps of contacting oxalate with a catalyst to prepare carbonate; the catalyst comprises 50-90 parts by weight of polystyrene resin and 10-50 parts by weight of quaternary phosphonium salt PR 1 R 2 R 3 X, based on the total parts by weight of the polystyrene resin and the quaternary phosphonium salt; wherein R is 1 、R 2 And R 3 Are each aryl or alkyl C a H b A is 2-10, b is 4-20; x is F, Cl, Br or I.)

1. A method for preparing carbonic ester by decarbonylation of oxalate comprises the steps of contacting oxalate with a catalyst to prepare carbonic ester; the catalyst comprises 50-90 parts by weight of polystyrene resin and 10-50 parts by weight of quaternary phosphonium salt PR₁R₂R₃X, based on the total parts by weight of the polystyrene resin and the quaternary phosphonium salt; wherein R is₁、R₂And R₃Are each aryl or alkyl C_aH_bA is 2-10, b is 4-20; x is F, Cl, Br or I.

2. The method for preparing carbonate by decarbonylation of oxalate according to claim 1, wherein the polystyrene resin is a divinylbenzene-crosslinked macroporous polystyrene resin.

3. The method for preparing carbonate by decarbonylation of oxalate according to claim 2, wherein the degree of crosslinking of the polystyrene resin is 1 to 20%.

4. The method for preparing carbonate by decarbonylation of oxalate according to claim 3, wherein the degree of crosslinking of the polystyrene resin is 2 to 10%.

5. The decarbonylation method for producing a carbonate ester according to claim 1, wherein a is 4 to 8, and b is 6 to 18; and X is Cl or Br.

6. The method for preparing carbonate by decarbonylation of oxalate according to claim 1, wherein the contacting conditions comprise: the temperature is 100-160 ℃.

7. The method for preparing carbonate by decarbonylation of oxalate according to claim 6, wherein the contacting conditions comprise: the temperature is 110-150 ℃.

8. The method for preparing carbonate by decarbonylation of oxalate according to claim 1, wherein the weight ratio of the catalyst to the oxalate is 0.005-0.5: 1.

9. The method for preparing carbonate by decarbonylation of oxalate according to claim 1, wherein the weight ratio of the catalyst to the oxalate is 0.01-0.5: 1.

10. The method for preparing carbonate by decarbonylation of oxalate according to claim 1, wherein the oxalate is dimethyl oxalate or diethyl oxalate.

Technical Field

The invention relates to a method for preparing carbonic ester by decarbonylation of oxalate.

Background

Dimethyl carbonate (DMC), which is active in chemical properties, excellent in physical properties, non-toxic and easily biodegradable, is a new low-pollution and environment-friendly green basic chemical raw material, can be used as a solvent, a gasoline additive, a lithium ion battery electrolyte and a carbonylation, methylation and carbonylmethoxylation reagent, and is widely applied to the field of chemical engineering. At present, the environmental-friendly chemical process based on DMC, an environmentally-friendly chemical raw material, is actively researched in all countries. The dimethyl oxalate comes from coal chemical industry, has wide raw material sources, and accords with the national situation of 'more coal and less oil' in China. Therefore, the decarbonylation of dimethyl oxalate to prepare dimethyl carbonate becomes a method with great industrial prospects.

Wangshen (Natural gas chemical, 2002, 27, 1-3) studied by PPh₄Cl is used as a catalyst for the reaction of decarbonylation of the diphenyl oxalate to generate the diphenyl carbonate, the optimal reaction condition is 260 ℃, the reaction time is 3 hours, and the yield of the obtained diphenyl carbonate is 97.8 percent. The reaction effect is good, but the reaction conditions are harsh. Studies on ZnCl as a material of chemical engineering, Natural gas, 2003, 28, 10-13₂The catalyst was used for the decarbonylation of diphenyl oxalate to produce diphenyl carbonate, and the yield of diphenyl carbonate was 21% by reacting at 260 ℃ for 3 hours. Helichrysum et al (South university Master thesis, research on diethyl oxalate gas phase catalytic decarbonylation to prepare diethyl carbonate, 2007) using K₂CO₃The catalyst/AC is used for the reaction of decarbonylation of diethyl oxalate to produce diethyl carbonate, the reaction temperature is 513K, and the airspeed is 800-1000 hours^-1The catalyst shows better catalytic activity, the conversion rate of DEO can reach 54.3 percent, the selectivity of DEC can reach 27.8 percent, and the space-time yield of DEC can reach 300.0g/(Lcat ∙ h). Harada et al (EP0916645,1998) from Uyu province₂CO₃The catalyst/AC is used for the reaction of decarbonylation of dimethyl oxalate to prepare dimethyl carbonate, the reaction is carried out at 205 ℃ for 2 hours, and the yield of DMO is 95 percent. But K₂CO₃Catalyst in the presence of water and CO₂In the presence of KHCO, the KHCO is easily generated₃Resulting in catalyst deactivation.

Disclosure of Invention

The invention aims to solve the technical problems of harsh reaction conditions, low catalyst activity and easy inactivation in the prior art, and provides a novel method for preparing carbonic ester by decarbonylation of oxalate. The method has the characteristics of mild reaction conditions, high catalyst activity and slow activity reduction.

Specifically, the invention relates to a method for preparing carbonate by decarbonylation of oxalate, which comprises the steps of contacting oxalate with a catalyst to prepare carbonate; the catalyst comprises 50-90 parts by weight of polystyrene resin and 10-50 parts by weight of quaternary phosphonium salt PR₁R₂R₃X, based on the total parts by weight of the polystyrene resin and the quaternary phosphonium salt; wherein R is₁、R₂And R₃Are each aryl or alkyl C_aH_bA is 2-10, b is 4-20; x is F, Cl, Br or I.

According to one aspect of the invention, the polystyrene resin is a divinylbenzene-crosslinked macroporous polystyrene resin.

According to an aspect of the present invention, the polystyrene resin has a crosslinking degree of 1 to 20%, preferably 2 to 10%.

According to one aspect of the invention, a is 4-8 and b is 6-18.

According to one aspect of the invention, X is Cl or Br.

According to one aspect of the invention, the contacting conditions comprise: the temperature is 100-160 ℃, preferably 110-150 ℃.

According to one aspect of the invention, the weight ratio of the catalyst to the oxalate is 0.005-0.5: 1, preferably 0.01-0.5: 1.

According to one aspect of the invention, the oxalate is dimethyl oxalate or diethyl oxalate.

The preparation method of the catalyst comprises the following steps: 1) chloromethyl resin and tertiary phosphine PR accounting for 20-100% of the mass of the chloromethyl resin₁R₂R₃And mixing the mixture with a solvent, and reacting for 2-40 hours at 60-160 ℃ to generate the chlorine type loaded quaternary phosphonium salt resin. Wherein R is₁、R₂And R₃Are each aryl or alkyl C_aH_bA is 2-10, preferably a is 4-8; b is 4-20, preferably 6-18. X is F, Cl, Br or I, preferably Cl or Br. The solvent is acetonitrile, benzonitrile, dimethylformamide, toluene, or dioxaneAt least one of toluene is used in an amount of 3 to 20 times the mass of the chloromethyl-type resin. 2) Mixing the chlorine type supported quaternary phosphonium salt resin with a halogen salt aqueous solution with the mass of 20-100%, reacting and filtering; repeating the above steps at least 3 times to produce the catalyst-supported quaternary phosphonium salt resin.

The invention has the technical effects that: according to the method, the supported quaternary phosphonium salt resin is used as the catalyst, covalent interaction exists between the quaternary phosphonium salt and the carrier, the deactivation is not easy, the catalyst activity is high, and the reaction condition is mild. According to the method, under the conditions that the reaction temperature is 140 ℃ and the weight ratio of the catalyst to the dimethyl oxalate is 0.1, the reaction is carried out for 3 hours, the conversion rate of the dimethyl oxalate is 98.5 percent, the selectivity of the dimethyl carbonate is 97.3 percent, and after the catalyst is repeatedly used for 10 times, the activity is reduced by less than 5 percent, thereby obtaining better technical effects.

Detailed Description

The following detailed description of the embodiments of the present invention is provided, but it should be noted that the scope of the present invention is not limited by the embodiments, but is defined by the appended claims.

All publications, patent applications, patents, and other references mentioned in this specification are herein incorporated by reference in their entirety. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present specification, including definitions, will control.

When the specification concludes with claims with the heading "known to those skilled in the art", "prior art", or the like, to derive materials, substances, methods, procedures, devices, or components, etc., it is intended that the subject matter derived from the heading encompass those conventionally used in the art at the time of filing this application, but also include those that are not currently in use, but would become known in the art to be suitable for a similar purpose.

It should be expressly understood that two or more of the aspects (or embodiments) disclosed in the context of this specification can be combined with each other as desired, and that such combined aspects (e.g., methods or systems) are incorporated in and constitute a part of this original disclosure, while remaining within the scope of the present invention.

Unless otherwise expressly indicated, all percentages, parts, ratios, etc. mentioned in this specification are by weight unless otherwise not in accordance with the conventional knowledge of those skilled in the art.

In the context of the present specification, the polystyrene resin PS is a divinylbenzene-crosslinked macroporous polystyrene resin. The degree of crosslinking refers to the weight of divinylbenzene in the resin as a percentage of the total weight of the resin.

The invention is further illustrated by the following specific examples.

[ example 1 ]

500g of Dimethylformamide (DMF), 100g of chloromethyl-type crosslinked polystyrene resin (Cl content: 18%, divinylbenzene crosslinking degree: 6.8%) and 90g of triphenylphosphine were added to a 1000mL three-necked flask, stirred, swelled for 4 hours, heated to 130 ℃, reacted for 4 hours, cooled, filtered, washed 3 times with DMF, ethanol and deionized water, and dried in an oven at 120 ℃ overnight to obtain a chlorine-type supported quaternary phosphonium salt resin catalyst C1.

The weight portion of the polystyrene resin substrate in the catalyst is 61 portions, and the quaternary phosphonium salt PR₁R₂R₃X is 39 parts, wherein R₁、R₂、R₃Are all phenyl groups, and X is Cl.

[ example 2 ]

Catalyst C1 was prepared according to the method described in [ example 1 ], and C150 g was added to a 1000mL beaker, followed by 500mL of 8% NaBr solution, and after standing for 4 hours, filtration was performed. After repeating the above procedure 3 times, the catalyst was washed 5 times with deionized water and dried in an oven at 120 ℃ overnight to give the supported quaternary phosphonium salt resin catalyst C2.

The weight portion of the polystyrene resin substrate in the catalyst is 54 portions, and the quaternary phosphonium salt PR₁R₂R₃X is 46 parts, wherein R₁、R₂、R₃Are all phenyl groups, and X is Br.

[ example 3 ]

500g of Benzonitrile (BN), 100g of chloromethyl-type crosslinked polystyrene resin (Cl content: 19%, degree of crosslinking of divinylbenzene: 2.5%) and 20g of tri-n-butylphosphine were added to a 1000mL three-necked flask, stirred, swelled for 4 hours, heated to 150 ℃ to react for 8 hours, cooled, filtered, washed 3 times with BN, ethanol and deionized water, and dried in an oven at 120 ℃ overnight to obtain the chloro-type supported quaternary phosphonium salt resin intermediate CM 1.

In a 1000mL beaker, 50g of intermediate CM1 was added, followed by 500mL of 8% NaBr solution, and after standing for 4 hours, filtration was carried out. After repeating the above procedure 3 times, the catalyst was washed 5 times with deionized water and dried in an oven at 120 ℃ overnight to give the supported quaternary phosphonium salt resin catalyst C3.

The weight portion of the polystyrene resin substrate in the catalyst is 85 portions, and the quaternary phosphonium salt PR₁R₂R₃X is 15 parts, wherein R₁、R₂、R₃Are all n-butyl and X is Br.

[ example 4 ]

Catalyst preparation was the same as [ example 3 ] except that the tertiary phosphine used was tricyclohexylphosphine, resulting in supported quaternary phosphonium salt resin catalyst C4.

The weight portion of the polystyrene resin substrate in the catalyst is 86 portions, and the quaternary phosphonium salt PR₁R₂R₃X is 14 parts, wherein R₁、R₂、R₃Are all cyclohexyl and X is Br.

[ example 5 ]

Catalyst preparation was the same as [ example 3 ] except that the tertiary phosphine used was triethylphosphine, resulting in supported quaternary phosphonium salt resin catalyst C5.

The weight portion of the polystyrene resin substrate in the catalyst is 80 portions, and the quaternary phosphonium salt PR₁R₂R₃The part of X is 20 parts, wherein R₁、R₂、R₃Are all ethyl groups, and X is Br.

[ example 6 ]

Catalyst preparation was the same as [ example 3 ] except that 500mL of 8% KI solution was used as the halide salt to give the supported quaternary phosphonium salt resin catalyst C6.

The weight portion of the polystyrene resin substrate in the catalyst is 84 portions, and the quaternary phosphonium salt PR₁R₂R₃X is 16 parts, wherein R₁、R₂、R₃Are both butyl groups, and X is I.

[ example 7 ]

Catalyst preparation was the same as [ example 3 ] except that 50g of tri-n-butylphosphine was used to obtain supported quaternary phosphonium salt resin catalyst C7.

The weight portion of the polystyrene resin substrate in the catalyst is 65 portions, and the quaternary phosphonium salt PR₁R₂R₃X is 35 parts, wherein R₁、R₂、R₃Are all n-butyl and X is Br.

[ example 8 ]

150g of dimethyl oxalate and 15g C1 catalyst were placed in a 500mL three-necked flask, the temperature was raised to 140 ℃ and the reaction was carried out for 3 hours, and the product was analyzed, the conversion of dimethyl oxalate was 67.1% and the selectivity of dimethyl carbonate was 87.5%.

[ examples 9 to 14 ]

The reaction conditions were the same as in example 6 except that the catalysts used were C2-C5, respectively, and the results are shown in Table 1.

TABLE 1

Catalyst and process for preparing same	Conversion of dimethyl oxalate (%)	Dimethyl carbonate selectivity (%)
			C2	98.5	97.3
C3	63.2	86.3
			C4	73.1	92.3
C5	59.6	92.5
			C6	60.1	91.2
C7	85.3	92.6

[ example 15 ]

The conditions were the same as in example 8 except that 50g of the catalyst was used, giving a conversion of dimethyl oxalate of 86.5% and a selectivity of dimethyl carbonate of 88.1%.

[ example 16 ]

The conditions were the same as in example 8 except that the reaction temperature was 150 ℃ to obtain a conversion of dimethyl oxalate of 88.8% and a selectivity of dimethyl carbonate of 91.2%.

[ example 17 ]

The mixed solution after completion of the reaction was filtered, and the catalyst was reused 10 times under the reaction conditions of example 8, to obtain the reaction results shown in table 2.

TABLE 2

Number of repeated use	Conversion of dimethyl oxalate (%)	Dimethyl carbonate selectivity (%)
			1	98.5	97.3
2	98.1	97.5
			3	98.0	97.1
4	97.5	97.2
			5	97.7	97.3
6	97.3	97.5
			7	97.1	97.3
8	97.0	97.6
			9	96.5	97.8
10	96.4	98.0