Method for preparing ethylene sulfate

Abstract

The invention discloses a method for preparing ethylene sulfate, which comprises the following steps: ethylene glycol and dimethyl sulfate react under the action of a metal catalyst and an auxiliary agent to obtain ethylene sulfate, the metal catalyst is a NiO-CuO / Al2O3 supported catalyst, and the auxiliary agent is one or more of sodium carbonate, potassium carbonate and sodium methoxide. The method is short in reaction process, relatively mild in reaction condition, relatively good in conversion rate and high in yield, and the purity of the obtained product is gt; 99%; the method is simple to operate, recyclable in catalyst, low in three-waste treatment cost, small in environmental pollution and relatively good in industrial application prospect.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis, specifically relating to a method for synthesizing vinyl sulfate. Background Technology

[0002] Ethylene sulfate (DTD) is an electrolyte interphase (SEI) film-forming additive, added at approximately 1% of the electrode. Its main functions are: 1) improving battery performance during high-temperature cycling, high-temperature storage, and low-temperature discharge; 2) reducing battery expansion after high-temperature storage, thus lowering capacity decay and internal resistance; 3) inhibiting initial capacity loss and increasing initial discharge capacity; and 4) enhancing the stability of graphite anodes and improving battery cycle performance. In addition, DTD can be used to synthesize antihypertensive drugs and as a raw material for novel dual surfactants. It has enormous application potential in both electrolyte additives and pharmaceutical intermediates.

[0003] Currently, the main method for synthesizing vinyl sulfate is to use ethylene glycol and thionyl chloride as starting materials to synthesize vinyl sulfite (CN117645596A, CN106187989A), followed by oxidation to obtain vinyl sulfate. The oxidation process primarily uses sodium hypochlorite (CN109369609A, CN109485633A) or hydrogen peroxide (CN109422719A) as oxidants. Using ethylene glycol and thionyl chloride as starting materials generates a large amount of hydrogen chloride, resulting in high equipment and waste treatment costs. Furthermore, the reaction is a two-step batch reaction with complex intermediate treatment processes, making operation difficult. Using inexpensive and readily available ethylene glycol and dimethyl sulfate via transesterification to obtain vinyl sulfate in one step is clearly a more direct method. There are reports of using cobalt octacarbonyl catalyzed reaction of ethylene glycol and dimethyl sulfate (CN112225719A), but this method is a homogeneous system, making catalyst recovery difficult and unsuitable for industrial production. Summary of the Invention

[0004] The purpose of this invention is to provide an efficient and low-cost one-step method for synthesizing vinyl sulfate.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] A method for preparing vinyl sulfate includes the following steps: ethylene glycol and dimethyl sulfate react in the presence of a metal catalyst and an auxiliary agent to obtain vinyl sulfate.

[0007] The reaction process is as follows:

[0008]

[0009] The metal catalyst is a NiO-CuO / Al2O3 supported catalyst.

[0010] The preparation method of the metal catalyst includes the following steps: Ni(NO3)2·6H2O, Cu(NO3)2·3H2O and Al2O3 powders are added to deionized water to prepare a mixed solution, mixed evenly at 50-70℃, preferably 60℃, allowed to stand, dehydrated, dried at 120-140℃, and calcined at 500-600℃, preferably 580℃, for 2-4 hours, preferably 2 hours, to obtain the NiO-CuO / Al2O3 catalyst.

[0011] Without being limited to any particular theory, the main mechanism of action of the metal catalyst may include: the metal coordinates with the oxygen atom in ethylene glycol to form an alcohol, increasing the nucleophilicity of the oxygen atom; subsequently, the metal approaches the sulfonyl group of dimethyl sulfate, increasing the electropositivity of the sulfur atom, thereby enabling the alcohol to combine with the sulfur atom and promoting the transesterification reaction.

[0012] The nickel oxide loading in the supported catalyst is 1%-10%, preferably 2%-6%.

[0013] The copper oxide loading in the supported catalyst is 1%-10%, preferably 4%-7%.

[0014] The mass ratio of the metal catalyst to ethylene glycol is 0.01 to 0.3:1, preferably 0.1 to 0.3:1.

[0015] The auxiliary agent is one or more combinations of sodium carbonate, potassium carbonate, and sodium methoxide, and its main function is to provide a slightly alkaline environment, which is conducive to the coordination of ethylene glycol and metal to form alkoxides. Sodium carbonate and potassium carbonate are preferred.

[0016] The molar ratio of the additive to ethylene glycol is 0.05 to 0.3:1, preferably 0.1 to 0.3:1.

[0017] The molar ratio of dimethyl sulfate to ethylene glycol is 1 to 2:1, preferably 1.5 to 2:1.

[0018] The reaction temperature is 50–100°C, preferably 70–100°C.

[0019] The reaction is carried out under vacuum, with a vacuum degree of 100–400 mmHg, preferably 200–400 mmHg.

[0020] After the reaction is completed, a crystallization step is included.

[0021] The solvent used in the crystallization step is one or more of dichloromethane, dichloroethane, dimethyl carbonate, diethyl carbonate, and ethyl acetate, preferably dichloromethane or dimethyl carbonate.

[0022] Compared with existing technologies, the significant advantages of this invention are as follows:

[0023] (1) The raw materials used, ethylene glycol and dimethyl sulfate, are inexpensive and readily available, do not require additional solvents, and dimethyl sulfate can be recycled, resulting in low cost.

[0024] (2) The reaction process is short, the reaction conditions are relatively mild, the conversion rate is good, the yield is high, and the purity of the obtained product is >99%.

[0025] (3) Using NiO-CuO / Al2O3 supported catalyst promotes the reaction, is easy to recover, and can be reused, which is beneficial to industrial production. Detailed Implementation

[0026] The above-mentioned solution will be further described below with reference to specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions used in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0027] Gas chromatography analysis conditions: Online analysis was performed using an Agilent HP-5 polysiloxane column with a two-stage temperature program: initial temperature 60°C, held for 1 minute, then increased to 80°C at a rate of 10°C / min; held for 1 minute, then increased to 250°C at a rate of 15°C / min, held for 5 minutes. High-purity N2 was used as the carrier gas with a split ratio of 30:1. The injection temperature was 250°C, and the detector was an FID with a detector temperature of 260°C. The injection volume was 1 μL.

[0028] Moisture and acidity determination: Follow the test methods in group standard T / CIESC 0042-2022.

[0029] In the following embodiments, unless otherwise specified, all raw materials are commercially available or prepared using conventional methods.

[0030] Example 1

[0031] Preparation of 2% NiO-4% CuO / Al2O3 catalyst:

[0032] Weigh 3.8936 g of Ni(NO3)2·6H2O, 6.0745 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder, add 1 L of deionized water to prepare a mixed solution, stir in a constant temperature water bath at 60 °C for 3 h to ensure uniform mixing of the support and nitrate, let stand in air for 26 h, and then place in a rotary evaporator at 90 °C for vacuum evaporation until the water evaporates. The resulting catalyst precursor is dried in an electric heating blast drying oven at 130 °C for 1 h, and then placed in a muffle furnace at 580 °C for 2 h to decompose the nitrate into a mixed oxide active component of NiO and CuO, thus obtaining a 2% NiO-4% CuO / Al2O3 catalyst.

[0033] Preparation of vinyl sulfate:

[0034] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (151.4 g, 1.2 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. 18.6 g of a 2% NiO-4% CuO / Al2O3 catalyst (mass ratio of 0.3 / 1 to ethylene glycol) and 30.4 g of potassium carbonate (0.22 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 50 °C. The vacuum was adjusted to 200 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved in dichloromethane and crystallized to obtain 100 g of white crystalline vinyl sulfate, with a yield of 81%, a purity of 99.2%, a water content of 30 ppm, and an acidity of 50 ppm.

[0035] Example 2

[0036] Preparation of 6% NiO-3% CuO / Al2O3 catalyst:

[0037] Weigh 11.6807 g of Ni(NO3)2·6H2O, 4.5559 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder, add 1 L of deionized water to prepare a mixed solution, stir in a constant temperature water bath at 55℃ for 3 h to ensure uniform mixing of the support and nitrate, let stand in air for 26 h, and then place in a rotary evaporator at 90℃ for vacuum evaporation until the water evaporates. The obtained catalyst precursor is dried in an electric heating blast drying oven at 125℃ for 1 h, and then placed in a muffle furnace at 540℃ for 2 h to decompose the nitrate into a mixed oxide active component of NiO and CuO, thus obtaining a 6% NiO-3% CuO / Al2O3 catalyst.

[0038] Preparation of vinyl sulfate:

[0039] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (151.4 g, 1.2 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. 6.2 g of a 6% NiO-3% CuO / Al2O3 catalyst (mass ratio to ethylene glycol 0.1 / 1) and 13.82 g of potassium carbonate (0.1 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 90 °C. The vacuum was adjusted to 400 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved in dichloromethane and crystallized to obtain 86.8 g of white crystalline ethylene sulfate, with a yield of 70%, purity of 99.4%, water content of 40 ppm, and acidity of 72 ppm.

[0040] Example 3

[0041] Preparation of 4% NiO-7% CuO / Al2O3 catalyst:

[0042] Weigh 7.7812 g of Ni(NO3)2·6H2O, 10.6305 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder, add 1 L of deionized water to prepare a mixed solution, stir in a constant temperature water bath at 65 °C for 3 h to ensure uniform mixing of the support and nitrate, let stand in air for 26 h, and then place in a rotary evaporator at 90 °C for vacuum evaporation until the water evaporates. The resulting catalyst precursor is dried in an electric heating drying oven at 137 °C for 1 h, and then placed in a muffle furnace at 510 °C for 1 h to decompose the nitrate into a mixed oxide active component of NiO and CuO, thus obtaining a 4% NiO-7% CuO / Al2O3 catalyst.

[0043] Preparation of vinyl sulfate:

[0044] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (126.1 g, 1 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. 18.6 g of a 4% NiO-7% CuO / Al2O3 catalyst (mass ratio of 0.3 / 1 to ethylene glycol), sodium carbonate (21.1980 g, 0.2 mol), and potassium carbonate (13.8206 g, 0.1 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 100 °C. The vacuum was adjusted to 100 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved in dichloromethane and crystallized to obtain 105.4 g of white crystalline vinyl sulfate, with a yield of 85%, purity of 99%, water content of 63 ppm, and acidity of 59 ppm.

[0045] The recycled catalyst was used to repeat the above steps to prepare vinyl sulfate. The product yield data are shown in Table 1 below.

[0046] Table 1 Catalyst Application

[0047]

[0048]

[0049] Example 4

[0050] Preparation of 1% NiO-7% CuO / Al2O3 catalyst:

[0051] Weigh 1.9468 g of Ni(NO3)2·6H2O, 10.6305 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder, add 1 L of deionized water to prepare a mixed solution, stir in a constant temperature water bath at 70 °C for 3 h to ensure uniform mixing of the support and nitrate, let stand in air for 26 h, and then place in a rotary evaporator at 100 °C for vacuum evaporation until the water evaporates. The resulting catalyst precursor is dried in an electric heating drying oven at 132 °C for 1 h, and then placed in a muffle furnace at 545 °C for 1.5 h to decompose the nitrate into a mixed oxide active component of NiO and CuO, thus obtaining a 1% NiO-7% CuO / Al2O3 catalyst.

[0052] Preparation of vinyl sulfate:

[0053] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (252.2 g, 2 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. 6.2 g of a 1% NiO-7% CuO / Al2O3 catalyst (mass ratio to ethylene glycol 0.1 / 1) and 10.5990 g of sodium carbonate (0.1 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 60 °C. The vacuum was adjusted to 200 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved in dichloromethane and crystallized to obtain 100.44 g of white crystalline vinyl sulfate, with a yield of 81%, purity of 99.1%, water content of 65 ppm, and acidity of 103 ppm.

[0054] Example 5

[0055] Preparation of 10% NiO-1% CuO / Al2O3 catalyst:

[0056] 19.4678 g of Ni(NO3)2·6H2O, 1.5186 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder were weighed and added to 1 L of deionized water to prepare a mixed solution. The solution was stirred in a constant temperature water bath at 70 °C for 3 h to ensure uniform mixing of the support and nitrate. The solution was then allowed to stand in air for 26 h and then vacuum evaporated at 90 °C in a rotary evaporator until the water content was completely evaporated. The resulting catalyst precursor was dried in an electric heating drying oven at 140 °C for 1 h and then calcined in a muffle furnace at 600 °C for 4 h to decompose the nitrate and generate a mixed oxide active component of NiO and CuO, thus preparing a 10% NiO-1% CuO / Al2O3 catalyst.

[0057] Preparation of vinyl sulfate:

[0058] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (252.2 g, 2 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. A 10% NiO-1% CuO / Al2O3 catalyst (mass ratio to ethylene glycol 0.01 / 1) (0.62 g) and sodium carbonate (26.4975 g, 0.25 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 60 °C. The vacuum was adjusted to 200 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved in dichloromethane and crystallized to obtain 89.28 g of white crystalline ethylene sulfate, with a yield of 72%, purity of 99.3%, water content of 69 ppm, and acidity of 75 ppm.

[0059] Example 6

[0060] Preparation of 3% NiO-10% CuO / Al2O3 catalyst:

[0061] Weigh 5.8403 g of Ni(NO3)2·6H2O, 15.1861 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder, add 1 L of deionized water to prepare a mixed solution, stir in a constant temperature water bath at 60 °C for 3 h to ensure uniform mixing of the support and nitrate, let stand in air for 26 h, and then place in a rotary evaporator at 90 °C for vacuum evaporation until the water evaporates. The obtained catalyst precursor is dried in an electric heating blast drying oven at 130 °C for 1 h, and then placed in a muffle furnace at 580 °C for 2 h to decompose the nitrate into a mixed oxide active component of NiO and CuO, thus obtaining a 3% NiO-10% CuO / Al2O3 catalyst.

[0062] Preparation of vinyl sulfate:

[0063] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (176.58 g, 1.4 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. 15.5 g of a 3% NiO-10% CuO / Al2O3 catalyst (mass ratio of 0.25 / 1 to ethylene glycol) and sodium methoxide (2.701 g, 0.05 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 85 °C. The vacuum was adjusted to 380 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved with dimethyl carbonate and crystallized to obtain 70.7 g of white crystalline ethylene sulfate, with a yield of 57%, a purity of 98.8%, a water content of 67 ppm, and an acidity of 72 ppm.

[0064] Example 7

[0065] Preparation of 3% NiO-10% CuO / Al2O3 catalyst:

[0066] Weigh 5.8403 g of Ni(NO3)2·6H2O, 15.1861 g of Cu(NO3)2·3H2O, and 50 g of Al2O3 powder, add 1 L of deionized water to prepare a mixed solution, stir in a constant temperature water bath at 60 °C for 3 h to ensure uniform mixing of the support and nitrate, let stand in air for 26 h, and then place in a rotary evaporator at 90 °C for vacuum evaporation until the water evaporates. The obtained catalyst precursor is dried in an electric heating blast drying oven at 130 °C for 1 h, and then placed in a muffle furnace at 580 °C for 2 h to decompose the nitrate into a mixed oxide active component of NiO and CuO, thus obtaining a 3% NiO-10% CuO / Al2O3 catalyst.

[0067] Preparation of vinyl sulfate:

[0068] Ethylene glycol (62 g, 1 mol) and dimethyl sulfate (151.4 g, 1.2 mol) were added to a 500 mL three-necked flask. A short-path distillation head and a condenser were connected. 6.2 g of a 3% NiO-10% CuO / Al2O3 catalyst (mass ratio of 0.1 / 1 to ethylene glycol) and 20.7309 g of potassium carbonate (0.15 mol) were added. The mixture was magnetically stirred at 600 rpm and heated to 50 °C. The vacuum was adjusted to 140 mmHg. The methanol generated in the system was transferred until no more methanol was generated. The mixture was cooled to room temperature and filtered. The filter residue was washed with dimethyl sulfate to recover the catalyst. The filtrate was collected and concentrated to recover dimethyl sulfate. The residue was dissolved with diethyl carbonate and crystallized to obtain 57.04 g of white crystalline vinyl sulfate, with a yield of 46%, a purity of 99.1%, a water content of 36 ppm, and an acidity of 79 ppm.

[0069] Comparative Example 1

[0070] Compared with Example 1, Comparative Example 1 differs in that no catalyst is added, but otherwise it is the same as Example 1, and the yield of the product is 0.

[0071] Comparative Example 2

[0072] Compared with Example 1, Comparative Example 1 differs in that no alkali additive is added, while the rest is the same as Example 1. The product yield is 44%, purity is 99.3%, water content is 56 ppm, and acidity is 78 ppm.

Claims

1. A process for the preparation of vinyl sulfate comprising the steps of: Ethylene glycol and dimethyl sulfate react in the presence of a metal catalyst and an auxiliary to obtain vinyl sulfate.

2. The method of claim 1, wherein, The metal catalyst is a NiO-CuO / Al2O3 supported catalyst.

3. The method of claim 1, wherein, The supported catalyst has a nickel oxide loading of 1-10%, preferably 2-6%.

4. The method of claim 1, wherein, The supported catalyst has a copper oxide loading of 1-10%, preferably 4-7%.

5. The method of claim 1, wherein, The mass ratio of the metal catalyst to ethylene glycol is 0.01-0.3:1, preferably 0.1-0.3:

1.

6. The method of claim 1, wherein, The auxiliary is one or more of sodium carbonate, potassium carbonate, and sodium methoxide.

7. The method of claim 1, wherein, The molar ratio of the auxiliary to ethylene glycol is 0.05-0.3:1, preferably 0.1-0.3:

1.

8. The method of claim 1, wherein, The molar ratio of dimethyl sulfate to ethylene glycol is 1-2:1, preferably 1.5-2:

1.

9. The method of claim 1, wherein, The reaction temperature is 50-100°C, preferably 70-100°C.

10. The method of claim 1, wherein, After the reaction, a crystallization step is included; the solvent used in the crystallization step is one or more of dichloromethane, dichloroethane, dimethyl carbonate, diethyl carbonate, and ethyl acetate.

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