Preparation process of trimethylene carbonate
The preparation of TMC by combining PDO and DMC under the catalysis of lipase or molecular sieve solves the problems of expensive catalysts and potential toxicity, achieving a safe and economical high-efficiency synthesis and promoting the application of TMC in the field of biodegradable materials.
Patent Information
- Application Number
- CN202411041802.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-31
- Publication Date
- 2026-02-03
AI Technical Summary
In the existing technology, the synthesis methods of trimethylene carbonate (TMC) have expensive catalysts with potential toxicity, making it difficult to achieve efficient synthesis that balances safety and economy, thus limiting its industrial application in fields such as biodegradable materials.
1,3-propanediol (PDO) and dimethyl carbonate (DMC) were reacted under the catalysis of lipase or molecular sieve to generate intermediates P1 and P2, which were then converted to 3-hydroxypropylmethyl carbonate (P1) under enzyme or non-enzyme catalysis. TMC was then prepared by thermal cyclization, avoiding the use of expensive lanthanum 2-ethylhexanoate catalyst.
This enables the efficient, safe, and economical synthesis of TMC, significantly enhancing its application potential in the field of biodegradable materials, reducing production costs, and improving environmental friendliness.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of polyester and polymer material preparation, and particularly relates to a preparation process of trimethylene carbonate. BACKGROUND
[0002] Trimethylene carbonate (TMC) has a wide application prospect in the fields of organic synthesis, battery electrolyte, biodegradable materials, etc. due to its unique six-membered ring structure and good ring-opening polymerization activity. In the field of organic synthesis, as a typical cyclic alkyl carbonate, TMC can be used as a solvent and an intermediate in a reaction, and can be used as an electrophile to introduce a hydroxyl group in a reaction, having great synthetic utility. In the field of battery electrolyte, the homopolymer of TMC, poly(trimethylene carbonate) (PTMC), is found to effectively dissolve alkali metal salts and reduce the tendency of ion aggregate formation, showing higher cycle stability, high capacity and coulombic efficiency compared to traditional lithium ion batteries, effectively promoting the research in the field of solvent-free solid polymer electrolyte based on lithium salt, and is expected to play a significant role in the field of solid-state lithium ion battery electrolyte. In the field of biodegradable materials, the homopolymer of TMC, PTMC, can resist non-enzyme hydrolysis in the body, and the hydrolysis product is a non-acidic substance, which can effectively solve the problem that the degradation of aliphatic polyester is too fast and the acidic substances produced during degradation can cause inflammatory reactions, thus cannot be applied in the medical field, opening a new window for the field of new biodegradable materials. TMC also has great application value in polymer modification. Studies have found that the integration of TMC as a block copolymer into polylactic acid (PLA) not only improves the mechanical properties of the copolymer, but also maintains its biodegradability. In addition to copolymerization, by simply blending PTMC with PLA and performing electrospinning to form a blend, the elongation at break of PLA is increased from 24.71% to 344.85%, and the blend can maintain good tissue compatibility while showing significant mechanical properties, which will further promote the practical application of PLA and become an excellent choice to replace petroleum-based plastics.
[0003] There are many synthesis methods of TMC with phosgene, carbon dioxide, carbonate, urea as carbonyl donor, propylene glycol, oxacycloalkane, halogenated alcohol as trimethylene donor. Among them, the ester exchange reaction of 1,3-propanediol and dimethyl carbonate (DMC) or diethyl carbonate (DEC) to synthesize TMC has wide raw material sources and low price, and has been concerned in recent years. There are studies that use lanthanum 2-ethylhexanoate as a catalyst to realize the reaction of PDO and DMC to prepare TMC. However, lanthanum 2-ethylhexanoate is expensive and has potential toxicity to the human body. It is urgent to develop new and more safe and economical high-efficiency synthesis technology to promote the industrialization process of TMC and expand the application of TMC in the production of high-value-added products such as biodegradable materials. SUMMARY
[0004] The purpose of the present application is to provide a new process for preparing trimethylene carbonate.
[0005] The present application is conceived as follows: a process for preparing trimethylene carbonate (TMC) by reacting 1,3-propanediol (PDO) and dimethyl carbonate (DMC) is provided. There are two preparation routes: route 1, PDO and DMC are reacted under the catalysis of lipase to prepare 3-hydroxypropyl methyl carbonate (P1) and C, C'-1,3-propanediyl, C, C'-dimethyl carbonate (P2), P2 is further converted into P1 under the catalysis of enzyme or non-enzyme, and P1 is converted into TMC; route 2, PDO and DMC are converted into P2 under the catalysis of molecular sieve, P2 is converted into P1 under the catalysis of enzyme or non-enzyme, and P1 is converted into TMC.
[0006] Specifically, PDO and DMC are reacted under the catalysis of lipase to generate P1 and P2, or PDO and DMC are synthesized into P2 under the catalysis of molecular sieve. P2 is further converted into P1, and the conversion of P2 to P1 can be that P2 is reacted with methanol under the catalysis of lipase to prepare P1, or P2 is reacted with PDO (PDO undergoes proton self-migration to act as an acid catalyst) to generate P1 under certain temperature conditions. P1 is further thermal cyclization to prepare TMC.
[0007] In order to achieve the purpose of the present application, the present application provides a preparation process of trimethylene carbonate, comprising the following steps: (1) 1,3-propanediol (PDO) and dimethyl carbonate (DMC) are reacted under the catalysis of lipase to generate 3-hydroxypropyl methyl carbonate (P1) and C, C'-1,3-propanediyl, C, C'-dimethyl carbonate (P2); or,
[0008] 1,3-propanediol and dimethyl carbonate are reacted under the catalysis of molecular sieve to generate C, C'-1,3-propanediyl, C, C'-dimethyl carbonate (P2); (2) C,C'-1,3-propanediyl, C,C'-dimethyl carbonate (P2) is converted into 3-hydroxypropyl methyl carbonate (P1) under the catalysis of enzyme or non-enzyme; (3) 3-hydroxypropyl methyl carbonate (P1) is prepared into trimethylene carbonate (TMC) through thermal cyclization.
[0009] Further, 1,3-propanediol and dimethyl carbonate in step (1) are reacted to generate 3-hydroxypropyl methyl carbonate and C,C'-1,3-propanediyl, C,C'-dimethyl carbonate under the catalysis of lipase.
[0010] The reaction conditions are as follows: the molar ratio of dimethyl carbonate to 1,3-propanediol is 3:1-9:1, the enzyme amount is 100-2000 U / g based on 1,3-propanediol, 3-8 g / g (based on 1,3-propanediol) of molecular sieve is further added, and the reaction is carried out at 40-60°C for 1-3 hours; wherein the molecular sieve is a molecular sieve with a size not less than that of methanol, including but not limited to 4A, 5A and 13X.
[0011] Further, 1,3-propanediol and dimethyl carbonate in step (1) are reacted to generate C,C'-1,3-propanediyl, C,C'-dimethyl carbonate under the catalysis of molecular sieve.
[0012] The reaction conditions are as follows: the molar ratio of dimethyl carbonate to 1,3-propanediol is 10:1-30:1, and the reaction is carried out at 100-150°C for 3-5 hours; wherein the molecular sieve includes but is not limited to 4A, ZSM-5, Hβ and Ti-MCM-41.
[0013] Further, C,C'-1,3-propanediyl, C,C'-dimethyl carbonate in step (2) is converted into 3-hydroxypropyl methyl carbonate under the catalysis of enzyme.
[0014] Specifically, C,C'-1,3-propanediyl, C,C'-dimethyl carbonate is reacted with methanol to generate 3-hydroxypropyl methyl carbonate under the catalysis of lipase.
[0015] The reaction conditions are as follows: the molar ratio of C,C'-1,3-propanediyl, C,C'-dimethyl carbonate to methanol is 1:1-1:5, the reaction is carried out at 30-50°C for 10-20 hours, and the enzyme amount is 100-2000 U / g based on C,C'-1,3-propanediyl, C,C'-dimethyl carbonate (P2); the reaction is carried out in a solvent-free system or in a system with tert-butyl alcohol, fatty acid methyl ester or fatty acid ethyl ester as a solvent.
[0016] Further, C,C'-1,3-propanediyl, C,C'-dimethyl carbonate in step (2) is converted into 3-hydroxypropyl methyl carbonate under the catalysis of non-enzyme.
[0017] Specifically, C,C'-1,3-propanediyl, C,C'-dicarbonic acid carbonate reacts with 1,3-propanediol (PDO) to generate 3-hydroxypropyl methyl carbonate under certain temperature conditions by proton self-migration as an acid catalyst.
[0018] The reaction conditions are as follows: the molar ratio of 1,3-propanediol to C,C'-1,3-propanediyl, C,C'-dicarbonic acid carbonate is 1:1-1:2, the reaction is carried out at 110-180℃ for 3-10 hours, and condensation reflux is adopted.
[0019] Further, the reaction conditions of step (3) are as follows: 110-180℃, 3-8 hours; condensation reflux is adopted after 2 hours of reaction.
[0020] In the present application, the lipase includes lipases derived from Rhizomucor miehei 、 Candida antarctica 、 Aspergillus oryzae and the like.
[0021] By means of the above technical solution, the present application has at least the following advantages and beneficial effects: Compared with the synthesis method in which phosgene, carbon dioxide, urea are used as a carbonyl donor and oxacycloalkane, halogenated alcohol are used as a trimethylene donor, the present application has obvious advantages such as wide raw material sources and low price in synthesizing TMC by ester exchange reaction of PDO and DMC. Compared with the technology in which lanthanum 2-ethylhexanoate is used as a catalyst to catalyze the reaction of PDO and DMC to prepare TMC, the present application has higher safety and economy, and has very important industrial application prospect. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1 The present application is a preparation process of bio-based trimethylene carbonate (TMC). DETAILED DESCRIPTION
[0023] The present application aims to provide a method for preparing trimethylene carbonate (TMC) by reacting 1,3-propanediol (PDO) and dimethyl carbonate (DMC).
[0024] The present application adopts the following technical solution: The reaction of the PDO and the DMC can be carried out under lipase catalysis to generate P1 and P2, P2 is further converted into P1 under enzyme catalysis or non-enzyme catalysis, and P1 is converted into TMC.
[0025] The PDO and the DMC are converted into P2 under molecular sieve catalysis, P2 is converted into P1 under enzyme catalysis or non-enzyme catalysis, and P1 is converted into TMC.
[0026] The lipase catalyzed reaction conditions of PDO and DMC are: the molar ratio of DMC to PDO is 3:1-9:1, the amount of enzyme is 100-2000 U / g (PDO), the amount of molecular sieve is 3-8 g / g (PDO), the reaction temperature is 40-60℃, and the reaction time is 1-3 hours. The molecular sieve is not less than the size of methanol, including but not limited to 4A, 5A and 13X.
[0027] The reaction of PDO and DMC can synthesize P2 under the catalysis of molecular sieve. The molecular sieve catalyzes 1,3-propanediol and dimethyl carbonate to generate P2 (the molar ratio of DMC to PDO is 20:1), the reaction temperature is 100-150℃, and the reaction time is 3-5 hours. The molecular sieve includes but is not limited to 4A, ZSM-5, Hβ and Ti-MCM-41.
[0028] The P2 is further converted to synthesize P1. The conversion can be that P2 reacts with methanol under the catalysis of lipase to prepare P1, or P2 reacts with PDO (PDO undergoes proton self-migration to act as an acid catalyst) to generate P1 under certain temperature conditions.
[0029] The lipase catalyzes the reaction of P2 and methanol to prepare P1. The reaction conditions are: the molar ratio of P2 to methanol is 1:1-1:5, the reaction temperature is 30-50℃, the reaction time is 10-30 hours, and the amount of enzyme is 100-2000 U / g (P2). The reaction can be carried out in a solvent-free system or in a system with tert-butyl alcohol, fatty acid methyl ester or fatty acid ethyl ester as a solvent.
[0030] The 1,3-propanediol undergoes proton self-migration to act as an acid catalyst to catalyze the reaction of 1,3-propanediol and P2. The reaction conditions are: the reaction temperature is 110-180℃, the reaction time is 3-10 hours, the condensation reflux is adopted, and the molar ratio of PDO to P2 is 1:1-1:2.
[0031] The P1 is heated to cyclize to prepare TMC. The reaction conditions are: the reaction temperature is 110-180℃, and the reaction time is 3-8 hours (the condensation reflux is adopted after 2 hours of reaction).
[0032] The preparation process of bio-based trimethylene carbonate (TMC) is shown in Figure 1 .
[0033] The following examples are used to illustrate the present application, but are not used to limit the scope of the present application. If not specifically indicated, the technical means used in the examples are conventional means known to those skilled in the art, and the raw materials used are commercially available.
[0034] Example 1
[0035] The lipase catalyzes the reaction of PDO and DMC: the molar ratio of DMC to PDO is 3:1 (20 g of PDO), the amount of enzyme is 100 units of standard enzyme activity per unit mass of PDO, and the reaction time is 24 hours.Rhizomucor miehei Lipase from Candida rugosa, 4A molecular sieves 3 g / g PDO, 40°C, 3 hours in a reactor suitable for the reaction catalyzed by the immobilized enzyme, P1 and P2 yields were 63.8%h and 30%, respectively.
[0036] Example 2
[0037] Lipase catalyzed reaction of PDO with DMC: molar ratio DMC to PDO 9:1 (20 g PDO), 2000 units of standard enzyme activity from Candida rugosa per gram of PDO, 5A molecular sieves 8 g / g PDO, 60°C, 1 hour in a reactor suitable for the reaction catalyzed by the immobilized enzyme, P1 and P2 yields were 65%h and 32%, respectively. Candida antarctica
[0038] Example 3
[0039] Lipase catalyzed reaction of PDO with DMC: molar ratio DMC to PDO 6:1 (20 g PDO), 1000 units of standard enzyme activity from Candida rugosa per gram of PDO, 13X molecular sieves 6 g / g PDO, 50°C, 2 hours in a reactor suitable for the reaction catalyzed by the immobilized enzyme, P1 and P2 yields were 64%h and 31%, respectively. Aspergillus oryzae
[0040] Example 4
[0041] Molecular sieves catalyzed synthesis of P2 from PDO and DMC: molar ratio PDO to DMC 1:5 (30 g PDO), 4A molecular sieves 5 g / g PDO, 100°C, 5 hours, P2 yield was 87%.
[0042] Example 5
[0043] Molecular sieves catalyzed synthesis of P2 from PDO and DMC: molar ratio PDO to DMC 1:20 (30 g PDO), ZSM-5 molecular sieves 110 g / g PDO, 150°C, 3 hours, P2 yield was 90%.
[0044] Example 6
[0045] Molecular sieves catalyzed synthesis of P2 from PDO and DMC: molar ratio PDO to DMC 1:10 (30 g PDO), Hβ molecular sieves 30 g / g PDO, 130°C, 4 hours, P2 yield was 92%.
[0046] Example 7
[0047] P2 synthesis from PDO and DMC catalyzed by molecular sieve: molar ratio of PDO to DMC is 1:30 (30g PDO), Ti-MCM-41 molecular sieve 50g / g PDO, 150℃, 3 hours, P2 yield is 95%.
[0048] Example 8
[0049] P1 synthesis from P2 and methanol catalyzed by lipase: molar ratio of P2 to methanol is 1:1 (10g P2), 30℃, 2000 units of standard enzyme activity of lipase from Candida rugosa per gram of P2, 10ml t-butyl alcohol system, reaction for 20 hours, P1 yield is 80%. Aspergillus oryzae
[0050] Example 9
[0051] P1 synthesis from P2 and methanol catalyzed by lipase: molar ratio of P2 to methanol is 1:5 (10g P2), 50℃, 100 units of standard enzyme activity of lipase from Candida rugosa per gram of P2, reaction for 30 hours, P1 yield is 70%. Candida antarctica
[0052] Example 10
[0053] P1 synthesis from P2 and methanol catalyzed by lipase: molar ratio of P2 to methanol is 1:3 (10g P2), 50℃, 1000 units of standard enzyme activity of lipase from Candida rugosa per gram of P2, 10ml fatty acid methyl ester system, reaction for 48 hours, P1 yield is 85%. Rhizomucor miehei
[0054] Example 11
[0055] 1,3-propanediol and P2 reaction catalyzed by 1,3-propanediol proton self-migration as acid catalyst: 110℃, condensation reflux, molar ratio of PDO to P2 is 1:1 (10g PDO), 16 hours, P2 conversion rate is 90%.
[0056] Example 12
[0057] 1,3-propanediol and P2 reaction catalyzed by 1,3-propanediol proton self-migration as acid catalyst: 180℃, condensation reflux, molar ratio of PDO to P2 is 1:2 (10g PDO), 10 hours, P2 conversion rate is 94%.
[0058] Example 13
[0059] TMC synthesis from P1 thermal cyclization: 30g P1, 110℃, condensation reflux after 2 hours, 8 hours TMC yield is 92%.
[0060] Example 14
[0061] TMC preparation by thermal cyclization of P1: 30g P1, 180℃, refluxed for 2 hours, TMC yield was 95% after 3 hours.
[0062] Example 15
[0063] The specific example of preparing P1 and P2 from PDO and DMC under lipase catalysis, and then converting P2 into P1 and P1 into TMC under enzyme catalysis is as follows: The molar ratio of DMC to PDO is 5:1 (100 g PDO), based on the source of 1500 standard enzyme activities per unit mass of PDO. Aspergillus oryzae Lipase was added to 15 g / g PDO using 5A molecular sieve and reacted at 55°C in a reactor suitable for immobilized enzyme catalysis for 6 hours, yielding 62% and 30% for P1 and P2, respectively. 40 g of this mixture was further subjected to thermal cyclization at 120°C, followed by reflux condensation for 2 hours, resulting in a 90% conversion of P1 to TMC after 5 hours. 30 g of the thermal cyclization product was then taken and added to methanol (P2 to methanol molar ratio 1:2). Based on 2000 standard enzyme activities per unit mass of P2, the enzyme was derived from… Rhizomucor miehei The lipase and fatty acid methyl ester (fatty acid methyl ester to methanol volume ratio of 10:1) were reacted for 12 hours, and the conversion rate from P2 to P1 was 90%. Further, 20g of this mixture was placed in a 140℃ hot cyclization chamber, and after 2 hours, reflux was applied. After 5 hours, the TMC yield was 94%.
[0064] Example 16
[0065] PDO and DMC are reacted to prepare P1 and P2 under lipase catalysis. P2 is then converted to P1 under non-enzymatic catalysis. A specific example of P1 being converted to TMC is as follows: The molar ratio of DMC to PDO is 4:1 (50 g PDO). The enzyme activity is based on 3000 standard enzyme activities per unit mass of PDO. Candida antarctica Lipase was added to a reactor containing 8 g / g PDO using 4A molecular sieve and reacted at 45°C for 4 hours in a reactor suitable for immobilized enzyme catalysis. The yields of P1 and P2 were 63% and 31%, respectively. Dimethyl carbonate and methanol (a byproduct) were then distilled off the system at 100°C to obtain a mixture of P1 and P2. 30 g of this mixture was subjected to thermal cyclization at 120°C for 2 hours, followed by reflux. After 6 hours, the conversion of P1 was 90%. 10 g of the reaction mixture was then added to react with PDO and P2 (PDO acts as an acid catalyst due to proton self-migration). The molar ratio of PDO to P2 was 1:2. The mixture was refluxed at 120°C for 8 hours, resulting in a total TMC yield of 95%.
[0066] Example 17
[0067] PDO and DMC were reacted to produce P2 under the catalysis of molecular sieve, P2 was converted to P1 under the catalysis of enzyme, and P1 was converted to TMC. The specific implementation was as follows: PDO and DMC were reacted to produce P2 under the catalysis of molecular sieve, and the specific conditions were that the molar ratio of PDO to DMC was 1:15 (100 g of PDO), the ZSM-5 molecular sieve was 150 g / g of PDO, the reaction was carried out at 150 DEG C for 3 hours, and the yield of P2 was 92%. Further, 60 g of the reaction mixture was taken, methanol (the molar ratio of P2 to methanol was 1:1.5), 1500 units of standard enzyme activity of lipase derived from Candida antarctica per unit mass of P2, and tert-butyl alcohol (the volume ratio of tert-butyl alcohol to methanol was 10:1) were added, and the reaction was carried out for 15 hours, and the yield of P1 was 85%. Further, 30 g of the mixture was placed in a hot cycle at 140 DEG C, and after 2 hours, condensation reflux was used, and after 5 hours, the yield of TMC was 94%. Aspergillus oryzae
[0068] Example 18
[0069] PDO and DMC were reacted to produce P2 under the catalysis of molecular sieve, P2 was converted to P1 under the catalysis of enzyme, and P1 was converted to TMC. The specific implementation was as follows: PDO and DMC were reacted to produce P2 under the catalysis of molecular sieve, and the specific conditions were that the molar ratio of PDO to DMC was 1:10 (300 g of PDO), the Hbeta molecular sieve was 30 g / g of PDO, the reaction was carried out at 130 DEG C for 4 hours, and the yield of P2 was 90%. Further, 60 g of the reaction mixture was taken, PDO was added for reaction (PDO was subjected to proton self-migration to serve as an acid catalyst), the molar ratio of PDO to P2 was 1:2, the reaction was carried out at 160 DEG C under condensation reflux, and after 6 hours, the yield of TMC was 95%.
[0070] The present application provides a preparation process for synthesizing trimethylene carbonate (TMC) from 1,3-propanediol (PDO) and dimethyl carbonate (DMC). Two preparation routes are included, that is, PDO and DMC are catalyzed by lipase to produce 3-hydroxypropyl methyl carbonate (P1) and C, C'-1,3-propanediyl, C, C'-dicarboxylic carbonate (P2), P2 is further converted to P1 under the catalysis of enzyme or non-enzyme, and P1 is converted to TMC; or PDO and DMC are converted to P2 under the catalysis of molecular sieve, P2 is converted to P1 under the catalysis of enzyme or non-enzyme, and P1 is converted to TMC. Figure 1 ). Specifically, PDO reacts with DMC under the catalysis of lipase to generate P1 and P2, or PDO reacts with DMC under the catalysis of molecular sieve to generate P2. P2 is further converted to generate P1. The conversion of P2 to P1 can be achieved by the reaction of P2 with methanol under the catalysis of lipase to generate P1, or the reaction of P2 with PDO (PDO acts as an acid catalyst due to proton self-migration) under certain temperature conditions to generate P1. P1 is further thermally cyclized to generate TMC. The present application uses different strategies to improve the conversion rate of PDO to P1, thereby further significantly improving the yield of TMC and significantly improving the environmental friendliness and economic benefits of the entire process, and has very important industrial application prospects.
[0071] Although the present application has been described in detail with general description and specific embodiments above, some modifications or improvements can be made on the basis of the present application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the present application, all belong to the scope of the present application claimed.
Claims
1. Process for the preparation of trimethylene carbonate, characterized in that, The method comprises the following steps: (1) 1,3-propanediol reacts with dimethyl carbonate under the catalysis of lipase to generate 3-hydroxypropyl methyl carbonate and C,C'-1,3-propanediyl,C,C'-dimethyl carbonate; or, 1,3-propanediol reacts with dimethyl carbonate under the catalysis of molecular sieve to generate C,C'-1,3-propanediyl,C,C'-dimethyl carbonate; (2) C,C'-1,3-propanediyl,C,C'-dimethyl carbonate is converted into 3-hydroxypropyl methyl carbonate under the catalysis of enzyme or non-enzyme; (3) 3-hydroxypropyl methyl carbonate is prepared by thermal cyclization to obtain trimethylene carbonate.
2. The process according to claim 1, characterized in that, Step (1) 1,3-propanediol reacts with dimethyl carbonate under the catalysis of lipase to generate 3-hydroxypropyl methyl carbonate and C,C'-1,3-propanediyl,C,C'-dimethyl carbonate; The reaction conditions are as follows: the molar ratio of dimethyl carbonate to 1,3-propanediol is 3:1-9:1, the amount of enzyme added is 100-2000 U / g based on 1,3-propanediol, 3-8 g / g of molecular sieve is further added, and the reaction is carried out at 40-60 ℃ for 1-3 hours; wherein the molecular sieve is a molecular sieve with a size not less than that of methanol, including 4A, 5A and 13X.
3. The process of claim 1, wherein, Step (1) 1,3-propanediol reacts with dimethyl carbonate under the catalysis of molecular sieve to generate C,C'-1,3-propanediyl,C,C'-dimethyl carbonate; The reaction conditions are as follows: the molar ratio of dimethyl carbonate to 1,3-propanediol is 10:1-30:1, and the reaction is carried out at 100-150 ℃ for 3-5 hours; wherein the molecular sieve includes 4A, ZSM-5, Hβ and Ti-MCM-41.
4. The process of claim 1, wherein, Step (2) C,C'-1,3-propanediyl,C,C'-dimethyl carbonate is converted into 3-hydroxypropyl methyl carbonate under the catalysis of enzyme; Specifically, C,C'-1,3-propanediyl,C,C'-dimethyl carbonate reacts with methanol under the catalysis of lipase to generate 3-hydroxypropyl methyl carbonate.
5. The process of claim 4, wherein, The reaction conditions are as follows: the molar ratio of C,C'-1,3-propanediyl,C,C'-dimethyl carbonate to methanol is 1:1-1:5, the reaction is carried out at 30-50 ℃ for 10-20 hours, and the amount of enzyme added is 100-2000 U / g based on C,C'-1,3-propanediyl,C,C'-dimethyl carbonate; the reaction is carried out in a solvent-free system or in a system with tert-butyl alcohol, fatty acid methyl ester or fatty acid ethyl ester as a solvent.
6. The process of claim 1, wherein, Step (2) C,C'-1,3-propanediyl,C,C'-dimethyl carbonate is converted into 3-hydroxypropyl methyl carbonate under the catalysis of non-enzyme; Specifically, C,C'-1,3-propanediyl,C,C'-dimethyl carbonate reacts with 1,3-propanediol under certain temperature conditions to generate 3-hydroxypropyl methyl carbonate.
7. The process of claim 6, wherein, The reaction conditions are as follows: the molar ratio of 1,3-propanediol to C,C'-1,3-propanediyl,C,C'-dimethyl carbonate is 1:1-1:2, the reaction is carried out at 110-180 ℃ for 3-10 hours, and condensation reflux is adopted.
8. The process of claim 1, wherein, The reaction conditions of step (3) are as follows: 110-180 ℃, 3-8 hours; condensation reflux is adopted after 2 hours of reaction.
9. The process according to any one of claims 1 to 8, characterized in that, The lipase includes a lipase derived from Rhizomucor miehei , Candida antarctica , Aspergillus oryzae a lipase.