A catalyst for preparing 1,2-butylene carbonate and its application

Abstract

An embodiment of the present invention discloses a catalyst for preparing 1,2-butylene carbonate and its application. A catalyst for preparing 1,2-butylene carbonate is prepared by loading hafnium oxide on a molecular sieve under heating conditions. The catalyst provided by the present invention is used for synthesizing 1,2-butylene carbonate, and has the advantages of high catalytic activity and strong reaction selectivity, can significantly improve the yield of 1,2-butylene carbonate, and has good industrial application prospects.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of fine chemical engineering, and particularly to a catalyst for preparing 1,2-butylene carbonate and its application. Background Art

[0002] 1,2-Butylene carbonate (BC) is a colorless and transparent liquid at room temperature. It is a low-toxic substance. Thermal decomposition will release toxic pungent and irritating fumes. It has a unique oxygen-containing five-membered heterocyclic structure and physical and chemical properties, and can be widely used in the fields of raw materials for producing polycarbonate and polyurethane, electrolyte solvents for lithium-ion batteries, aprotic polar solvents, etc. Its structure is as follows:

[0003]

[0004] Currently, 1,2-butylene carbonate is mainly synthesized by the cycloaddition of carbon dioxide and alkylene oxide, which is a typical atom-economic reaction and conforms to the development direction of green chemistry. However, the existing synthesis methods have problems of low activity and reaction selectivity of the catalyst, resulting in a low yield of the target product. Summary of the Invention

[0005] Therefore, embodiments of the present invention provide a catalyst for preparing 1,2-butylene carbonate and its application.

[0006] In order to achieve the above object, embodiments of the present invention provide the following technical solutions:

[0007] According to the first aspect of the embodiments of the present invention, the present invention provides a catalyst for preparing 1,2-butylene carbonate. Under heating conditions, hafnium oxide is loaded on a molecular sieve to obtain the catalyst.

[0008] Further, the molecular sieve is a zeolite molecular sieve or a mesoporous molecular sieve. As an example, the zeolite molecular sieve can be A-type, Y-type, X-type, ZSM-5 type, etc., and the mesoporous molecular sieve is SAB-15, MCM-41, etc.

[0009] Further, the mass ratio of hafnium oxide to the molecular sieve is 1:1 to 1.5.

[0010] Further, the heating temperature is 500 - 600 °C and the time is 8 - 10 h.

[0011] According to the second aspect of the embodiments of the present invention, the present invention provides the application of the above-mentioned catalyst in the preparation of 1,2-butylene carbonate.

[0012] According to a third aspect of the embodiments of the present invention, the present invention provides a method for preparing 1,2-butenyl carbonate, using butylene oxide and carbon dioxide as raw materials, and reacting in the presence of a catalyst as described in any one of the above items.

[0013] Furthermore, the reaction pressure is 2-5 MPa and the temperature is 195-225°C.

[0014] Furthermore, the mass ratio of the catalyst to butylene oxide is 0.04-0.07:1; the mass ratio of butylene oxide to carbon dioxide is 1:0.6-0.8.

[0015] Furthermore, the method also includes: purifying the reaction product, and the purification specifically includes: distilling the reaction product at a pressure of -0.09 to -0.10 MPa and a temperature of 140 to 170°C, and rectifying the obtained fraction at -0.09 to -0.10 MPa and a temperature of 160 to 190°C to obtain 1,2-butenyl carbonate.

[0016] The embodiments of the present invention have the following advantages:

[0017] The catalyst provided by the present invention is used for synthesizing 1,2-butenyl carbonate, has the advantages of high catalytic activity and strong reaction selectivity, can significantly improve the yield of 1,2-butenyl carbonate, and has good industrial application prospects. DETAILED DESCRIPTION

[0018] The following describes the implementation of the present invention using specific embodiments. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. Obviously, the embodiments described are only a portion of the present invention, not all of it. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0019] Example 1

[0020] This embodiment provides a catalyst, and its preparation method is as follows:

[0021] Hafnium oxide and molecular sieve were mixed in a mass ratio of 1:1, and then placed in a centrifugal mixer for thorough stirring. The mixture was placed in a crucible and heated at 500° C. for 8 h to obtain a catalyst.

[0022] Example 2

[0023] This embodiment provides a catalyst, and its preparation method is as follows:

[0024] Hafnium oxide and molecular sieve were mixed in a mass ratio of 1:1.2, and then placed in a centrifugal mixer for thorough stirring. The mixture was placed in a crucible and heated at 550° C. for 8 h to obtain a catalyst.

[0025] Example 3

[0026] This embodiment provides a catalyst, and its preparation method is as follows:

[0027] Hafnium oxide and molecular sieve were mixed in a mass ratio of 1:1.5, and then placed in a centrifugal mixer for thorough stirring. The mixture was placed in a crucible and heated at 600° C. for 10 h to obtain a catalyst.

[0028] Comparative Example 1

[0029] This comparative example provides a catalyst, which differs from Example 1 in that an equal amount of titanium dioxide is used to replace hafnium oxide.

[0030] Comparative Example 2

[0031] This comparative example provides a catalyst, which differs from Example 1 in that an equal amount of zinc oxide is used to replace hafnium oxide.

[0032] Comparative Example 3

[0033] This comparative example provides a catalyst, which is hafnium oxide.

[0034] Example 4

[0035] This embodiment provides a method for preparing 1,2-butenyl carbonate:

[0036] 15 g of the catalyst of Example 1 was added to a 2000 mL autoclave, and high-purity nitrogen was introduced into the reactor for displacement three times. 300 g of butylene oxide was introduced to 4 MPa. After the temperature was raised to 200 ° C, 195 g of carbon dioxide was slowly introduced. The reaction was continued for 5 h, and the heating was stopped. The gas in the autoclave was first discharged, and then distilled at -0.10 MPa and 150 ° C. The distilled fraction was introduced into a distillation tower for distillation. The pressure of the distillation tower was controlled at -0.10 MPa and the temperature was 180 ° C. 482.4 g of 1,2-butenyl carbonate was produced from the side line with a purity of 99.94% and a yield of 99.8%.

[0037] Example 5

[0038] This embodiment provides a method for preparing 1,2-butenyl carbonate:

[0039] 18 g of the catalyst of Example 2 was added to a 2000 mL autoclave. High-purity nitrogen was introduced to displace the reaction kettle three times. 300 g of epoxybutane was introduced to 4 MPa. After heating to 200 °C, 204 g of carbon dioxide was slowly introduced. The reaction was carried out for 5 h. After stopping heating, the gas in the high-pressure reaction kettle was discharged first, and then distillation was carried out at -0.099 Mpa and 160 °C. The distilled fraction was introduced into a rectification column for rectification. The pressure of the rectification column was controlled at -0.099 MPa, and the temperature was 190 °C. 482.4 g of 1,2-butylene carbonate with a purity of 99.93% was collected from the side line, and the yield was 99.8%.

[0040] Example 6

[0041] This example provides a method for preparing 1,2-butylene carbonate:

[0042] 21 g of the catalyst of Example 3 was added to a 2000 mL autoclave. High-purity nitrogen was introduced to displace the reaction kettle three times. 300 g of epoxybutane was introduced to 4 MPa. After heating to 100 °C, 186 g of carbon dioxide was slowly introduced. The reaction was carried out for 5 h. After stopping heating, the gas in the high-pressure reaction kettle was discharged first, and then distillation was carried out at -0.10 Mpa and 150 °C. The distilled fraction was introduced into a rectification column for rectification. The pressure of the rectification column was controlled at -0.099 MPa, and the temperature was 180 °C. 481.9 g of 1,2-butylene carbonate with a purity of 99.93% was collected from the side line, and the yield was 99.7%.

[0043] Comparative Example 4

[0044] This comparative example provides a method for preparing 1,2-butylene carbonate, which is only different from Example 4 in that the catalyst of Comparative Example 1 is used. The results show that 478.1 g of 1,2-butylene carbonate was collected from the side line, with a purity of 97.21% and a yield of 84.0%.

[0045] Comparative Example 5

[0046] This comparative example provides a method for preparing 1,2-butylene carbonate, which is only different from Example 4 in that the catalyst of Comparative Example 2 is used. The results show that 421.5 g of 1,2-butylene carbonate was collected from the side line, with a purity of 97.35% and a yield of 87.2%.

[0047] Comparative Example 6

[0048] This comparative example provides a method for preparing 1,2-butylene carbonate, which is only different from Example 4 in that the catalyst of Comparative Example 3 is used. The results show that 438.2 g of 1,2-butylene carbonate was collected from the side line, with a purity of 98.85% and a yield of 90.7%.

[0049] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made thereto based on the present invention, which will be obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of the present invention claimed.

Claims

1. Use of a catalyst in the preparation of 1,2-butylene carbonate, characterized in that, The preparation method of the catalyst is as follows: under heating conditions, load hafnium oxide on molecular sieve to obtain the catalyst; The molecular sieve is one of A-type, Y-type, X-type, ZSM-5 type, SAB-15, and MCM-41; The mass ratio of hafnium oxide to molecular sieve is 1:1 to 1.5; The temperature of the heating is 500 to 600 °C, and the time is 8 to 10 h; The 1,2-butylene carbonate uses epoxy butane and carbon dioxide as raw materials.

2. A method for preparing 1,2-butylene carbonate, characterized in that, Using epoxy butane and carbon dioxide as raw materials, carry out the reaction in the presence of the catalyst as described in claim 1.

3. The method according to claim 2, characterized in that The pressure of the reaction is 2 to 5 MPa, and the temperature is 195 to 225 °C.

4. The method according to claim 2, wherein The mass ratio of the catalyst to epoxy butane is 0.04 to 0.07:1; the mass ratio of epoxy butane to carbon dioxide is 1:0.6 to 0.

8.

5. The method according to claim 2, wherein The method further includes: purifying the reaction product, and the purification specifically includes: distilling the reaction product at a pressure of -0.09 to -0.10 MPa and a temperature of 140 to 170 °C, and rectifying the obtained fraction at a pressure of -0.09 to -0.10 MPa and a temperature of 160 to 190 °C to obtain 1,2-butylene carbonate.

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