Method for preparing gamma-butyrolactone
By carrying out the hydrodehydrogenation coupling reaction of 1,4-butanediol and dimethyl maleate under temporary hydrogen conditions, and using metal catalysts such as copper or nickel, the problems of low selectivity and high cost of γ-butyrolactone in the prior art are solved, and efficient and safe industrial production is achieved.
Patent Information
- Application Number
- CN202410037678.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-10
- Publication Date
- 2025-07-11
AI Technical Summary
The method for preparing γ-butyrolactone in the prior art has problems such as low selectivity, high cost, serious equipment corrosion, short catalyst life and difficulty in industrialization.
The gas-phase 1,4-butanediol and gas-phase dimethyl maleate are used to conduct a hydrodehydrogenation coupling reaction under hydrogen conditions. A catalyst containing metals such as copper or nickel is used to control the reaction temperature and pressure, and a fixed bed, slurry bed or fluidized bed reactor is used to carry out the reaction.
It improves the selectivity and atomic yield of γ-butyrolactone, reduces production costs, reduces hydrogen consumption, avoids equipment corrosion, and is suitable for industrial continuous production.
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Figure BDA0004658434680000081
Abstract
Description
Technical Field
[0001] The present application relates to the field of organic synthesis, and specifically, to a method for preparing γ-butyrolactone. Background Art
[0002] γ-butyrolactone (hereinafter referred to as GBL) is an important fine chemical raw material and organic chemical intermediate, and has characteristics such as high boiling point, strong conductivity, and good stability. As an organic solvent, γ-butyrolactone has extremely strong solubility and can dissolve epoxy resin, polypropylene, polyvinyl chloride and its copolymers, fiber polymers, etc. In the petrochemical industry, γ-butyrolactone is an ideal antioxidant, plasticizer, dispersant, color fixing agent, coagulant, etc.; in the pharmaceutical industry, γ-butyrolactone can be used as an anesthetic and sedative, etc.; in the agricultural and forestry industries, γ-butyrolactone is an intermediate for plant growth agents, insecticides, etc. With the development of the lithium battery industry, the demand for γ-butyrolactone at home and abroad has been increasing day by day, and in recent years, it has been used in large amounts especially in the synthesis of important chemical products such as pyrrolidone, vinyl pyrrolidone, and N-methyl pyrrolidone.
[0003] At present, the main methods for preparing γ-butyrolactone are 1,4-butanediol dehydrogenation method and maleic anhydride hydrogenation method. The 1,4-butanediol dehydrogenation method generally adopts gas-phase dehydrogenation method, which is a medium exothermic reaction. In traditional processes, copper-based catalysts are used. At normal pressure, 200-270 °C, liquid hourly space velocity 0.1-3 hr -1 -1, the selectivity of γ-butyrolactone is greater than 93%. Due to the endothermic reaction, in the actual production process, affected by heat transfer, its high liquid hourly space velocity cannot achieve the expected high production capacity. And due to the uneven temperature distribution in the catalyst bed layer, there are also a small amount of by-products such as tetrahydrofuran, butanol, and high-boiling substances generated, and the by-product hydrogen is currently mostly vented or used as fuel, with low utilization efficiency, making γ-butyrolactone lose market price competitiveness. The maleic anhydride hydrogenation method includes maleic anhydride liquid-phase hydrogenation method, maleic anhydride gas-phase hydrogenation method, and maleic anhydride esterification hydrogenation method. Maleic anhydride is a solid at normal temperature. Directly using maleic anhydride as a raw material requires finding a suitable solvent, which increases the difficulty of product separation and raw material loss. And the preparation of γ-butyrolactone by the maleic anhydride hydrogenation method is a strong exothermic reaction, and it is easy to cause untimely local heat dissipation in a fixed-bed reactor, which intensifies side reactions such as deep hydrogenation and hydrogenolysis, resulting in low selectivity of γ-butyrolactone, short catalyst life, low space-time efficiency, and unstable operation of the production device. This process has been gradually phased out. For the maleic anhydride esterification hydrogenation method, the raw material is first esterified with methanol to obtain dimethyl maleate, and then hydrogenated to obtain γ-butyrolactone. Compared with the direct hydrogenation method of maleic anhydride, the liquid hourly space velocity of the raw material is significantly increased, the impurity content in the crude product is significantly reduced, and the separation is relatively easy, but this process route is complex and the production cost is high.
[0004] In the prior art, there is also a method for preparing γ-butyrolactone using maleic anhydride and 1,4-butanediol as raw materials. This method has problems such as high corrosion to equipment, high catalyst cost, and inability to continuously produce due to raw material polymerization, and is not suitable for industrial production. Summary of the Invention
[0005] The object of the present disclosure is to provide a method for preparing γ-butyrolactone, which has good selectivity for γ-butyrolactone, low production cost, significantly improved atomic yield and thermal energy utilization rate, high production process safety, and is suitable for industrial continuous production.
[0006] To achieve the above object, the present disclosure provides a method for preparing γ-butyrolactone, which includes: under hydrogenation conditions and in the presence of a catalyst, contacting gaseous 1,4-butanediol and gaseous dimethyl maleate to carry out a hydrogenation-dehydrogenation coupling reaction to prepare γ-butyrolactone.
[0007] Optionally, the molar ratio of the amount of hydrogen used to the total molar amount of dimethyl maleate and 1,4-butanediol is 1-1000, preferably 1-500, more preferably 10-300, and further preferably 20-100.
[0008] Optionally, the conditions of the hydrogenation-dehydrogenation coupling reaction include: temperature is 150-300 °C, reaction pressure is 0.05-3 MPa, and liquid hourly space velocity is 0.01-2 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4-butanediol.
[0009] Optionally, the conditions of the hydrogenation-dehydrogenation coupling reaction include: temperature is 160-250 °C, reaction pressure is 0.1-1 MPa, and liquid hourly space velocity is 0.05-1 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4-butanediol.
[0010] Optionally, the conditions of the hydrogenation-dehydrogenation coupling reaction include: temperature is 180-220 °C, reaction pressure is 0.1-0.5 MPa, and liquid hourly space velocity is 0.1-0.5 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4-butanediol.
[0011] Optionally, the method includes: vaporizing liquid dimethyl maleate and liquid 1,4-butanediol to obtain gaseous 1,4-butanediol and gaseous dimethyl maleate.
[0012] Optionally, the molar ratio of dimethyl maleate to 1,4-butanediol is 1:(0.5-5), preferably 1:(1-3), and more preferably 1:(1.5-2).
[0013] Optionally, the catalyst contains a carrier, a metal active component, and a metal promoter; the metal in the metal active component is selected from copper or nickel, preferably copper, and the metal in the metal promoter is selected from one or more of Zn, Co, Mo, Ni, Wu, Fe, and Cr; the carrier is selected from one or more of Al2O3 or SiO2.
[0014] Optionally, based on the dry basis weight of the catalyst, the content of the metal active component in terms of metal oxide is 30-50% by weight, and the content of the metal promoter in terms of metal oxide is 20-40% by weight.
[0015] Optionally, the hydrodehydrogenation coupling reaction is carried out in a fixed bed reactor, a slurry bed reactor, or a fluidized bed reactor.
[0016] By the above technical solutions, the method of the present disclosure has the following beneficial effects:
[0017] (1) The hydrodehydrogenation coupling reaction of the present disclosure has good selectivity for γ-butyrolactone, high atomic yield, and easy control of reaction conditions;
[0018] (2) The hydrodehydrogenation coupling reaction of the present disclosure couples the highly exothermic hydrogenation reaction of dimethyl maleate with the moderately endothermic dehydrogenation reaction of 1,4-butanediol. The hydrodehydrogenation coupling reaction is a slightly exothermic reaction, effectively reducing the reaction energy consumption, and can in-situ and fully utilize the hydrogen by-produced from the dehydrogenation of 1,4-butanediol, greatly reducing the hydrogen consumption and significantly reducing the production cost;
[0019] (3) The method of the present disclosure can use a catalyst with low cost without precious metals, and dimethyl maleate will not polymerize and block the pipeline during the reaction process, and the production process will not cause corrosion problems to the equipment. The method of the present disclosure has high safety, low investment cost, and is suitable for industrial continuous production.
[0020] Other features and advantages of the present disclosure will be described in detail in the following specific implementation section. Specific Embodiments
[0021] The following details the specific embodiments of the present disclosure. It should be understood that the specific embodiments described herein are only for explaining and illustrating the present disclosure, and are not used to limit the present disclosure.
[0022] The present disclosure provides a method for preparing γ-butyrolactone, which includes: under hydrogenation conditions and in the presence of a catalyst, contacting gaseous 1,4-butanediol with gaseous dimethyl maleate to carry out a hydrodehydrogenation coupling reaction to prepare γ-butyrolactone.
[0023] The method of the present disclosure uses dimethyl maleate and 1,4-butanediol as raw materials, coupling the highly exothermic hydrogenation reaction of dimethyl maleate with the moderately endothermic dehydrogenation reaction of 1,4-butanediol. Among them, the highly active atomic hydrogen released from 1,4-butanediol can be directly used in the hydrogenation process of dimethyl maleate, and the heat released from the hydrogenation of dimethyl maleate can also be used for the dehydrogenation of 1,4-butanediol. The hydrogenation-dehydrogenation coupling reaction is complementary in terms of heat and materials, and both generate the same target product γ-butyrolactone, thereby effectively improving the atomic yield and thermal energy utilization rate, greatly reducing the hydrogen consumption, lowering the production cost, and having a high selectivity for γ-butyrolactone. Moreover, this method uses a catalyst without precious metals, the cost of the catalyst is relatively low, dimethyl maleate will not polymerize and block the pipeline during the reaction process, and the production process will not cause corrosion problems to the equipment. The method of the present disclosure has high safety and low investment cost, and is suitable for industrial continuous production.
[0024] In a specific embodiment of the present disclosure, the molar ratio of the amount of hydrogen used to the total molar amount of dimethyl maleate and 1,4-butanediol is 1-1000, preferably 1-500, more preferably 10-300, and further preferably 20-100. The above dosage ratio range is appropriate, which can further reduce the production cost and improve the atomic yield and thermal energy utilization rate.
[0025] In a specific embodiment of the present disclosure, the conditions for the hydrogenation-dehydrogenation coupling reaction include: the temperature is 150-300 °C, the reaction pressure is 0.05-3 MPa, and the liquid hourly space velocity is 0.01-2 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4-butanediol.
[0026] In a preferred specific embodiment of the present disclosure, the conditions for the hydrogenation-dehydrogenation coupling reaction include: the temperature is 160-250 °C, the reaction pressure is 0.1-1 MPa, and the liquid hourly space velocity is 0.05-1 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4-butanediol.
[0027] In a more preferred specific embodiment of the present disclosure, the conditions for the hydrogenation-dehydrogenation coupling reaction include: the temperature is 180-220 °C, the reaction pressure is 0.1-0.5 MPa, and the liquid hourly space velocity is 0.1-0.5 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4-butanediol. In the above preferred embodiment, the selectivity for γ-butyrolactone can be further improved, the production cost can be further reduced, and the thermal energy utilization rate can be further improved.
[0028] According to the present disclosure, the method includes: vaporizing liquid dimethyl maleate and liquid 1,4-butanediol to obtain gaseous 1,4-butanediol and gaseous dimethyl maleate. According to the present disclosure, the vaporization can be carried out in a manner commonly used by those skilled in the art. For example, liquid dimethyl maleate and liquid 1,4-butanediol can be introduced into a vaporization chamber for vaporization.
[0029] According to the present disclosure, the molar ratio of the amount of dimethyl maleate to 1,4-butanediol can vary within a relatively large range. In a specific embodiment of the present disclosure, the molar ratio of the amount of dimethyl maleate to the amount of 1,4-butanediol is 1:(0.5 - 5), preferably 1:(1 - 3), and more preferably 1:(1.5 - 2). The dosage ratio within the above range is appropriate, which can further reduce the production cost and improve the atomic yield and thermal energy utilization rate.
[0030] In a specific embodiment of the present disclosure, the catalyst contains a carrier, a metal active component, and a metal promoter; the metal in the metal active component is selected from one or more of copper or nickel, preferably copper, and the metal in the metal promoter is selected from one or more of Zn, Co, Mn, Ni, Wu, Fe, and Cr; the carrier is selected from one or more of Al2O3 or SiO2.
[0031] In a specific embodiment of the present disclosure, based on the dry weight of the catalyst, the content of the metal active component in terms of metal oxide is 30 - 50% by weight, and the content of the metal promoter in terms of metal oxide is 20 - 40% by weight; preferably, the content of the metal active component in terms of metal oxide is 35 - 45% by weight, and the content of the metal promoter in terms of metal oxide is 25 - 35% by weight.
[0032] In a specific embodiment of the present disclosure, the catalyst is a catalyst that has been subjected to a reduction treatment. The reduction treatment is well-known to those skilled in the art. For example, it can be carried out in a hydrogen-nitrogen mixed gas. The hydrogen content in the hydrogen-nitrogen mixed gas is 0.1 - 1% by volume, the starting temperature of the reduction is 20 - 30 °C, the first target temperature is 170 - 190 °C, the heating rate is 5 - 15 °C / min, and the heat preservation time is 1 - 5 h. Preferably, after heating to the first target temperature, the hydrogen content in the hydrogen-nitrogen mixed gas is 1 - 2% by volume, and then it is heated to the second target temperature of 190 - 210 °C and kept warm for 10 - 20 h.
[0033] In a specific embodiment of the present disclosure, the hydrodehydrogenation coupling reaction is carried out in a fixed-bed reactor, a slurry-bed reactor, or a fluidized-bed reactor. Preferably, a fixed-bed reactor is used for the hydrodehydrogenation coupling reaction.
[0034] The present disclosure will be further illustrated by the following examples, but the present disclosure is not limited thereby.
[0035] The raw materials used in the following examples and comparative examples are all commercially available unless otherwise specified.
[0036] In the catalysts used in Examples 1 to 8, the metal in the metal active component is copper, the metal in the metal promoter is manganese, and the carrier is alumina. Based on the dry weight of the catalyst, the content of the metal active component in terms of metal oxide is 40% by weight, and the content of the metal promoter in terms of metal oxide is 30% by weight.
[0037] Example 1
[0038] γ-Butyrolactone was prepared by a hydrogenation-dehydrogenation coupling reaction in a fixed-bed continuous flow reactor (a stainless steel tube with an inner diameter of Φ150 mm and a length of 1000 mm, with a thermocouple thermometer sleeve with an outer diameter of 50 mm placed in the middle). Specifically, generally, 18 g (about 13 mL) of a copper-based catalyst was placed into the reaction tube, and the catalyst bed was filled with quartz balls at both ends. Before each evaluation, the catalyst needed to be reduced with a hydrogen-nitrogen mixture. Before reduction, the reactor was purged with N2 to ensure no air residue. After the catalyst was heated to 180 °C at a rate of 10 °C / min in a 0.5 vol% H2 / N2 atmosphere, the hydrogen concentration was gradually increased to 2.0% and then heated to 200 °C, and then the hydrogen concentration was increased to 100% and activated overnight.
[0039] After the catalyst reduction was completed, the temperature was adjusted to the reaction temperature. A liquid mixture of dimethyl maleate and 1,4-butanediol was pumped into the vaporization chamber by a high-pressure liquid pump, and the generated steam was sent into the reactor by hydrogen to contact the catalyst bed for a coupling reaction. The liquid-phase product was collected every 4 h after condensation and analyzed offline by GC-FID after sampling.
[0040] At a reaction temperature of 190 °C, a reaction pressure of 0.2 MPa, and a liquid hourly space velocity (LHSV) of 0.1 h -1 (liquid hourly space velocity based on the mixed solution of dimethyl maleate and 1,4-butanediol), with a molar ratio of dimethyl maleate to 1,4-butanediol in the feed of 1:1.5 and a hydrogen-to-feed molar ratio (i.e., the ratio of the molar amount of hydrogen used to the sum of the molar amounts of dimethyl maleate and 1,4-butanediol) of 100, the reaction was carried out. The conversion of dimethyl maleate, the conversion of 1,4-butanediol, and the total selectivity of γ-butyrolactone are shown in Table 1 below, and the same applies hereinafter.
[0041] Example 2
[0042] γ-Butyrolactone was prepared in the same manner as in Example 1, except that the hydrogen-to-feed molar ratio was 300.
[0043] Example 3
[0044] γ-butyrolactone was prepared by the same method as in Example 1, except that the molar ratio of hydrogen to feedstock was 450.
[0045] Example 4
[0046] γ-butyrolactone was prepared by the same method as in Example 1, except that the molar ratio of hydrogen to feedstock was 600.
[0047] Example 5
[0048] γ-butyrolactone was prepared by the same method as in Example 1, except that the reaction temperature was 170 °C, the reaction pressure was 0.6 MPa, and the liquid hourly space velocity (LHSV) was 0.07 h -1 。
[0049] Example 6
[0050] γ-butyrolactone was prepared by the same method as in Example 1, except that the reaction temperature was 260 °C, the reaction pressure was 1.2 MPa, and the liquid hourly space velocity (LHSV) was 0.03 h -1 。
[0051] Example 7
[0052] γ-butyrolactone was prepared by the same method as in Example 1, except that the molar ratio of dimethyl maleate to 1,4-butanediol in the feed was 1:1.2.
[0053] Comparative Example 1
[0054] Maleic anhydride and 1,4-butanediol were reacted at a molar ratio of 1:1.55 and a liquid feed space velocity of 1.5 h -1 at a rate under the action of hydrogen and a catalyst, the reaction pressure was 0.08 MPa, the reaction temperature was 200 °C, the molar ratio of H2 to the maleic anhydride / 1,4-butanediol mixture was 50, and the catalyst used had a composition of CuO:RuO2:Sm2O3 of 5:4:1. Then, the reaction product was separated and purified, and the analysis results are shown in Table 1.
[0055] Table 1
[0056]
[0057] As can be seen from the above, the method of the present disclosure has good selectivity for γ-butyrolactone, low production cost, and significantly improved atomic yield and thermal energy utilization rate. Although the effect of preparing γ-butyrolactone in Comparative Example 1 is also good, a copper-based catalyst containing 40% noble metal ruthenium oxide needs to be used in its method, and maleic anhydride is prone to polymerization and adhesion, causing pipeline blockage and production interruption. The reaction of maleic anhydride with the water generated during the hydrogenation process to form maleic acid will corrode the production equipment, and its equipment investment cost and production cost will be significantly higher than those of the method of the present disclosure.
[0058] The preferred embodiments of the present disclosure have been described in detail above. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.
[0059] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, without conflict, they can be combined in any suitable manner. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination methods.
[0060] Furthermore, any combination can be made between various different embodiments of the present disclosure, as long as it does not violate the idea of the present disclosure, it should also be regarded as the content disclosed by the present disclosure.
Claims
1. A method for preparing γ-butyrolactone, characterized in that, The method includes: under a hydrogenation condition and in the presence of a catalyst, bringing gaseous 1,4-butanediol and gaseous dimethyl maleate into contact to carry out a hydrogenation dehydrogenation coupling reaction to prepare γ-butyrolactone.
2. The method according to claim 1, wherein The molar ratio of the amount of hydrogen used to the total molar amount of dimethyl maleate and 1,4-butanediol is 1 - 1000, preferably 1 - 500, more preferably 10 - 300, and further preferably 20 - 100.
3. The method according to claim 1, wherein The conditions for the hydrodehydrogenation coupling reaction include: the temperature is 150 - 300 °C, the reaction pressure is 0.05 - 3 MPa, and the liquid hourly space velocity is 0.01 - 2 h -1 , and the liquid hourly space velocity is calculated based on the total amount of liquid of dimethyl maleate and 1,4 - butanediol.
4. The method according to claim 1, wherein, The conditions of the hydrodehydrogenation coupling reaction include: temperature of 160 - 250 °C, reaction pressure of 0.1 - 1 MPa, and liquid hourly space velocity of 0.05 - 1 h -1 , and the liquid hourly space velocity is calculated based on the total amount of the liquid of dimethyl maleate and 1,4 - butanediol.
5. The method according to claim 1, wherein The conditions for the hydrodehydrogenation coupling reaction include: the temperature is 180 - 220 °C, the reaction pressure is 0.1 - 0.5 MPa, and the liquid hourly space velocity is 0.1 - 0.5 h -1 , and the liquid hourly space velocity is calculated based on the total liquid amount of dimethyl maleate and 1,4 - butanediol.
6. The method according to claim 1, wherein, The method includes: vaporizing liquid dimethyl maleate and liquid 1,4-butanediol to obtain gaseous 1,4-butanediol and gaseous dimethyl maleate.
7. The method according to claim 1, wherein The molar ratio of the amount of dimethyl maleate used to the amount of 1,4-butanediol is 1:(0.5 - 5), preferably 1:(1 - 3), more preferably 1:(1.5 - 2).
8. The method according to claim 1, wherein The catalyst contains a carrier, a metal active component, and a metal promoter; the metal in the metal active component is selected from copper or nickel, preferably copper, and the metal in the metal promoter is selected from one or more of Zn, Co, Mo, Ni, Wu, Fe, and Cr; the carrier is selected from one or more of Al2O3 or SiO2.
9. The method according to claim 8, wherein Based on the dry weight of the catalyst, the content of the metal active component in terms of metal oxide is 30 - 50% by weight, and the content of the metal promoter in terms of metal oxide is 20 - 40% by weight.
10. The method according to claim 1, wherein, The hydrogenation dehydrogenation coupling reaction is carried out in a fixed bed reactor, a slurry bed reactor, or a fluidized bed reactor.