CN113845507A - Method for removing water and chloride ions in fluoroethylene carbonate - Google Patents
Method for removing water and chloride ions in fluoroethylene carbonate Download PDFInfo
- Publication number
- CN113845507A CN113845507A CN202110990393.5A CN202110990393A CN113845507A CN 113845507 A CN113845507 A CN 113845507A CN 202110990393 A CN202110990393 A CN 202110990393A CN 113845507 A CN113845507 A CN 113845507A
- Authority
- CN
- China
- Prior art keywords
- fluoroethylene carbonate
- hydride
- metallic
- chloride ions
- removing water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D317/00—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms
- C07D317/08—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3
- C07D317/10—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3 not condensed with other rings
- C07D317/32—Heterocyclic compounds containing five-membered rings having two oxygen atoms as the only ring hetero atoms having the hetero atoms in positions 1 and 3 not condensed with other rings with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D317/42—Halogen atoms or nitro radicals
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for removing water and chloride ions in fluoroethylene carbonate, which comprises the steps of firstly removing water by using an alkaline drying agent until the water content is less than or equal to 30ppm, so that metal cation pollution is avoided after reaction, simultaneously removing the chloride ions, and then dynamically cooling and crystallizing to obtain crystals with uniform size, thereby avoiding the large-area sticking of the crystals to walls, being easy to operate in the subsequent filtering process, not adopting heating in the whole water removal process, being simple and convenient to operate, and avoiding the problems of large energy consumption, complicated steps, low efficiency and high water content in the traditional heating and distilling method.
Description
The technical field is as follows:
the invention relates to the technical field of purification, and particularly relates to a method for removing water and chloride ions in fluoroethylene carbonate.
Background art:
fluoroethylene carbonate (FEC for short) is used as an electrolyte additive of the lithium battery, can form a compact structure layer without increasing the impedance of the electrolyte, can prevent the electrolyte from being further decomposed, and has good high and low temperature performance and an anti-ballooning function. Meanwhile, the electrolyte can promote the formation of an SEI film, improve the recycling performance of the battery and improve the comprehensive performance of the electrolyte.
In order to obtain fluoroethylene carbonate with higher purity, the purification is generally carried out by multistage rectification in industry. However, this method has several disadvantages: firstly, due to the high boiling point of fluoroethylene carbonate, the energy consumption is very high by adopting a multi-stage rectification method, which is not beneficial to energy conservation and emission reduction of enterprises; secondly, the residual moisture content is higher. The fluoroethylene carbonate is used as an important lithium battery electrolyte additive, the requirement on water is extremely high, a small amount of water can cause the reduction of the battery cycle performance and the reduction of the battery capacity and even damage the battery, and the high content of residual water can directly influence the use of the fluoroethylene carbonate as the additive in the lithium battery, so that higher requirements are provided for the purification process of the fluoroethylene carbonate.
The preparation method of fluoroethylene carbonate reported at present is mostly obtained by carrying out fluorination reaction on chloroethylene carbonate and potassium fluoride, the preparation method inevitably causes obvious residue of chloride ions in products, the purification method adopted for post-treatment purification is mostly a mode of directly distilling crude products, and a special chloride ion removal process is lacked, so that the content of the chloride ions in the products is large in fluctuation, and the quality of the products is unstable. The residual amount of chloride ions is high, and the performance of the lithium ion battery is reduced when the lithium ion battery is used.
CN106810527A discloses a preparation method of high-purity fluoroethylene carbonate, which comprises the steps of adsorbing chloride ions by using a hydrotalcite adsorbent, adding a molecular sieve, activated carbon, montmorillonite or activated alumina drying agent, and finally putting into internal circulation type membrane molecular distillation equipment for molecular distillation, but the preparation method has the problems of complicated steps and high energy consumption.
If a method for purifying fluoroethylene carbonate with low cost, high product quality and low chloride ion and moisture content can be developed, the method has high industrial application value.
The invention content is as follows:
the invention aims to provide a method for removing water and chloride ions in fluoroethylene carbonate, which comprises the steps of firstly removing water with an alkaline drying agent until the water content is less than or equal to 30ppm, so that metal cation pollution cannot be generated after reaction, simultaneously removing the chloride ions, and then dynamically cooling and crystallizing to obtain crystals with uniform size, thereby preventing the crystals from being adhered to walls in a large area, being easy to operate in the subsequent filtering process, not adopting heating in the whole water removal process, being simple and convenient to operate, and avoiding the problems of large energy consumption, complicated steps, low efficiency and high water content in the traditional heating and distilling method.
The invention is realized by the following technical scheme:
a method for removing water and chloride ions in fluoroethylene carbonate comprises the following steps:
(1) dissolving a fluoroethylene carbonate crude product with the purity of more than or equal to 95% by using an organic solvent to obtain a solution with the mass concentration of 55% -85%, preferably 65% -75%, wherein the organic solvent is selected from any one of esters, carbonates, nitriles, ethers, halogenated alkanes and aromatic compounds, adding an alkaline drying agent, stirring and drying until the water content of a system is less than or equal to 30ppm and the pH of the system is neutral, standing and layering, and filtering the liquid obtained by centrifuging the supernatant to obtain a clear filtrate; the alkaline desiccant is one or more of lithium hydride, sodium hydride, potassium hydride, calcium hydride, magnesium hydride, barium hydride, beryllium hydride, strontium hydride, cesium hydride, rubidium hydride, lithium aluminum hydride, metallic lithium, metallic sodium, metallic potassium, metallic rubidium, metallic cesium, metallic beryllium, metallic calcium, metallic magnesium, metallic strontium and metallic barium;
(2) injecting the clear filtrate obtained in the step (1) into a temperature-controllable crystallization kettle, reducing the temperature from 50 ℃ to-25 ℃, preferably from 30 ℃ to-10 ℃, and gradually reducing the temperature for dynamic crystallization for 1-12 hours, preferably for 4-8 hours;
(3) after the crystallization is finished, filtering treatment is carried out at the low temperature of-20 ℃ to obtain the fluoroethylene carbonate crystal product.
In the step (1), the ester is selected from one or more combinations of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate and vinyl acetate, the carbonate is selected from one or more combinations of dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate, the nitrile is selected from one or more combinations of acetonitrile, propionitrile and isopropylnitrile, the ether is selected from one or more combinations of diethyl ether, propyl ether, tert-butyl methyl ether, tert-butyl ethyl ether, tetrahydrofuran, dioxane, nonafluorobutyl methyl ether and nonafluorobutyl ethyl ether, the halogenated alkane is selected from one or more combinations of dichloromethane, trichloromethane, carbon tetrachloride, dichloroethane, trichloroethane, bromoethane, dibromoethane, iodomethane and iodoethane, and the aromatic compound is selected from one or more combinations of benzene, toluene, xylene and trimethylbenzene.
In the step (1), the adding amount of the alkaline drying agent is 5-20% of the mass of the fluoroethylene carbonate, and preferably 10-15%.
The invention has the beneficial effects that:
1) before crystallization, an alkaline drying agent is used for dewatering until the water content is less than or equal to 30ppm, so that the problem of high water content of a fluoroethylene carbonate product is solved;
2) the alkaline drying agent can effectively remove water and chloride ions in the system, chlorinated metal salt generated by removing the chloride ions can be directly removed by centrifugal filtration, so that the chlorine removal is complete, metal cation pollution is avoided, the content of the obtained product chloride ions is extremely low, the fluctuation is small, and the product quality is improved;
3) the crystal particles obtained by dynamic cooling crystallization are uniform in size, and the quality of the product is improved. Meanwhile, the method can avoid the occurrence of large-area wall sticking of crystals, is easy to operate in the subsequent filtering process, and is suitable for industrial production.
4) Heating is not adopted in the whole process of water removal, the operation is simple and convenient, and the problems of large energy consumption, complicated steps, low efficiency and high water content in the traditional heating distillation method are solved.
In a word, the invention firstly uses the alkaline drying agent to remove water until the water content is less than or equal to 30ppm, so that metal cation pollution can not be generated after reaction, simultaneously, chloride ions are removed, and then the temperature is dynamically reduced for crystallization, the size of the obtained crystal is uniform, the phenomenon that the crystal is adhered to the wall in a large area can be avoided, the operation is easy in the subsequent filtration process, heating is not adopted in the whole process of removing water, the operation is simple and convenient, and the problems of large energy consumption, complicated steps, low efficiency and high water content in the traditional heating distillation method are avoided.
The specific implementation mode is as follows:
the following is a further description of the invention and is not intended to be limiting.
Example 1:
in a 200L reaction kettle, 108kg of fluoroethylene carbonate crude product and 72kg of anhydrous dimethyl carbonate are added, and then 10.8kg of calcium hydride is added for stirring reaction, wherein the stirring speed of a stirring paddle is set to 350 rpm. The water content is monitored and measured on line by adopting a Karl Fischer water measuring method, and the pH value is monitored on line by adopting a pH meter. When the water content is less than or equal to 20ppm and the pH value is neutral, stopping stirring, standing for 2 hours, after solid and liquid are layered, conveying the supernatant liquid to a centrifugal machine for centrifugal treatment, and conveying the obtained centrifugal liquid to a filter for filtration treatment. And conveying the obtained clear liquid to a temperature-controllable crystallization kettle. The stirring system was started at a stirring rate of 250rpm, the temperature control system was set to decrease from the initial 30 ℃ to the final 8 ℃ and the temperature decrease time was set to 4 hours. After the crystallization process is finished, the crystal is conveyed to a three-in-one filter (filtration, washing and blowing) while the temperature is 8 ℃, and the filtration precision is 300 meshes. The obtained crystals are washed for 1 time by adopting anhydrous dimethyl carbonate, and dried nitrogen is adopted for blowing for 0.5 hour after washing, so that the washing and blowing ensure that the crystallization mother liquor can be completely separated from the crystals. After the blowing is completed, the crystals are transferred to a storage tank, and when the temperature is restored to 23 ℃ or more, the crystals are melted into a liquid. 97.0kg was weighed. Yield: 90.6 percent. The liquid was taken for analysis. The GC-MS purity was 99.94%. And (3) trace detection result: ICP-OES (ppm): k+＝2.107ppm，Na+＝7.528ppm，Fe2+＝0.638ppm，Ca2 +＝7.921ppm；Mg2+＝0.187ppm；IC：F－＝7.26ppm，Cl－＝5.09ppm，NO3 －＝1.07ppm，SO4 2-＝2.14ppm，PO4 3-＝2.04ppm。KF：H2O＝8.91ppm。
Example 2
This example was conducted in substantially the same manner as in example 1 except that the organic solvent used in this example was toluene. The product obtained in this example weighed 97.4kg last. Yield: 90.2 percent. The liquid was taken for analysis. The GC-MS purity was 99.95%. And (3) trace detection result: ICP-OES (ppm): k+＝3.422ppm，Na+＝4.274ppm，Fe2+＝0.186ppm，Ca2 +＝8.071ppm；Mg2+＝0.314ppm；IC：F－＝1.34ppm，Cl－＝5.33ppm，NO3 －＝3.51ppm，SO4 2-＝1.23ppm，PO4 3-＝1.86ppm。KF：H2O＝7.88ppm。
Example 3
This example operates substantially the same as example 1, except that the alkaline drying agent of this example is lithium hydride. The product obtained in this example weighed 96.2kg last. Yield: 89.1 percent. The liquid was taken for analysis. The GC-MS purity was 99.95%. And (3) trace detection result: ICP-OES (ppm): k+＝1.902ppm，Na+＝8.218ppm，Fe2+＝0.093ppm，Ca2 +＝1.933ppm；Mg2+＝0.163ppm；IC：F－＝4.14ppm，Cl－＝8.05ppm，NO3 －＝4.71ppm，SO4 2-＝5.03ppm，PO4 3-＝0.93ppm。KF：H2O＝9.01ppm。
Example 4
In a 200L reaction kettle, 140kg of fluoroethylene carbonate crude product and 60kg of anhydrous dichloromethane are added, and then 10.5kg of metal sodium is added for stirring reaction, wherein the stirring speed of a stirring paddle is set to 350 rpm. The water content is monitored and measured on line by adopting a Karl Fischer water measuring method, and the pH value is monitored on line by adopting a pH meter. When the water content is less than or equal to 20ppm and the pH value is neutral, stopping stirring, standing for 2 hours, after solid and liquid are layered, conveying the supernatant liquid to a centrifugal machine for centrifugal treatment, and conveying the obtained centrifugal liquid to a filter for filtration treatment. And conveying the obtained clear liquid to a temperature-controllable crystallization kettle. The stirring system was started at a stirring rate of 250rpm and the temperature control system was set up fromThe initial 30 ℃ was decreased to the end-point-5 ℃ and the temperature decrease time was set to 6 hours. After the crystallization process is finished, the crystal is conveyed to a three-in-one filter (filtration, washing and blowing) while the temperature is minus 5 ℃, and the filtration precision is 300 meshes. The obtained crystals are washed for 1 time by adopting anhydrous dichloromethane, the pressure of dry nitrogen blowing is adopted for 0.5 hour after washing, and washing and blowing ensure that the crystallization mother liquor can be completely separated from the crystals. After the blowing was completed, the crystals were transferred to a storage tank when the temperature was restored to 23 ℃ or more. The crystals melt into a liquid. 129.2kg was weighed. Yield: 92.3 percent. The liquid was taken for analysis. The GC-MS purity was 99.93%. And (3) trace detection result: ICP-OES (ppm): k+＝1.721ppm，Na+＝12.802ppm，Fe2+＝0.381ppm，Ca2+＝3.407ppm；Mg2+＝0.112ppm；IC：F－＝8.48ppm，Cl－＝6.83ppm，NO3 －＝2.58ppm，SO4 2-＝3.7ppm，PO4 3-＝1.67ppm。KF：H2O＝6.49ppm。
Example 5
This example was conducted in substantially the same manner as in example 4 except that the organic solvent used in this example was tetrahydrofuran. The product obtained in this example weighed 128.4kg last. Yield: 91.7 percent. The liquid was taken for analysis. The GC-MS purity was 99.94%. And (3) trace detection result: ICP-OES (ppm): k+＝1.696ppm，Na+＝14.015ppm，Fe2+＝0.232ppm，Ca2+＝4.611ppm；Mg2+＝0.284ppm；IC：F－＝6.04ppm，Cl－＝8.21ppm，NO3 －＝3.71ppm，SO4 2-＝2.46ppm，PO4 3-＝2.03ppm。KF：H2O＝7.02ppm。
Example 6
This example operates substantially the same as example 4, except that the alkaline desiccant of this example is calcium metal. The product obtained in this example weighed 129.9kg last. Yield: 92.8 percent. The liquid was taken for analysis. The GC-MS purity was 99.96%. And (3) trace detection result: ICP-OES (ppm): k+＝1.852ppm，Na+＝3.744ppm，Fe2+＝0.189ppm，Ca2 +＝8.992ppm；Mg2+＝0.151ppm；IC：F－＝2.53ppm，Cl－＝7.08ppm，NO3 －＝4.82ppm，SO4 2-＝1.75ppm，PO4 3-＝1.18ppm。KF：H2O＝5.74ppm。
Example 7
This example was conducted in substantially the same manner as in example 6 except that the organic solvent used in this example was changed to ethyl acetate. The product obtained in this example weighed 129.1kg last. Yield: 92.2 percent. The liquid was taken for analysis. The GC-MS purity was 99.95%. And (3) trace detection result: ICP-OES (ppm): k+＝2.017ppm，Na+＝2.911ppm，Fe2+＝0.204ppm，Ca2+＝1.51ppm；Mg2+＝0.078ppm；IC：F－＝1.98ppm，Cl－＝6.49ppm，NO3 －＝4.19ppm，SO4 2-＝2.16ppm，PO4 3-＝2.02ppm。KF：H2O＝6.08ppm。
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (7)
1. A method for removing water and chloride ions in fluoroethylene carbonate is characterized by comprising the following steps:
(1) dissolving a fluoroethylene carbonate crude product with the purity of more than or equal to 95% by using an organic solvent to obtain a solution with the mass concentration of 55% -85%, wherein the organic solvent is selected from any one of esters, carbonates, nitriles, ethers, halogenated alkanes and aromatic compounds, then adding an alkaline drying agent, stirring and drying until the water content of a system is less than or equal to 30ppm and the pH of the system is neutral, standing and layering, centrifuging an upper layer liquid to obtain a liquid, and filtering to obtain a clear filtrate; the alkaline desiccant is one or more of lithium hydride, sodium hydride, potassium hydride, calcium hydride, magnesium hydride, barium hydride, beryllium hydride, strontium hydride, cesium hydride, rubidium hydride, lithium aluminum hydride, metallic lithium, metallic sodium, metallic potassium, metallic rubidium, metallic cesium, metallic beryllium, metallic calcium, metallic magnesium, metallic strontium and metallic barium;
(2) injecting the clear filtrate obtained in the step (1) into a temperature-controllable crystallization kettle, reducing the temperature from 50 ℃ to-25 ℃ for 1-12 hours, and gradually reducing the temperature for dynamic crystallization;
(3) after the crystallization is finished, filtering treatment is carried out at the low temperature of-20 ℃ to obtain the fluoroethylene carbonate crystal product.
2. The method for removing water and chloride ions in fluoroethylene carbonate according to claim 1, wherein in the step (1), a fluoroethylene carbonate crude product with the purity of not less than 95% is dissolved by an organic solvent to obtain a solution with the mass concentration of 65% -75%, then an alkaline drying agent is added, the solution is stirred and dried until the water content of the system is not more than 30ppm and the pH of the system is neutral, the solution is kept stand for layering, and the supernatant is centrifuged to obtain a liquid, and then the liquid is filtered to obtain a clear filtrate.
3. The method for removing water and chloride ions in fluoroethylene carbonate according to claim 1 or 2, wherein the step (2) is: and (2) injecting the clear filtrate obtained in the step (1) into a temperature-controllable crystallization kettle, cooling the temperature from 30 ℃ to-10 ℃ for 4-8 hours, and gradually cooling for dynamic crystallization.
4. The method for removing water and chloride ions from fluoroethylene carbonate according to claim 1 or 2, wherein in step (1), the ester is selected from one or more combinations of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate and vinyl acetate, the carbonate is selected from one or more combinations of dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate, the nitrile is selected from one or more of acetonitrile, propionitrile and isopropylnitrile, the ether is selected from one or more combinations of diethyl ether, propyl ether, tert-butyl methyl ether, tert-butyl ethyl ether, tetrahydrofuran, dioxane, nonafluorobutyl methyl ether and nonafluorobutyl ethyl ether, the halogenated alkane is selected from one or more combinations of dichloromethane, trichloromethane, carbon tetrachloride, dichloroethane, trichloroethane, bromoethane, dibromoethane, iodomethane and iodoethane, the aromatic compound is selected from one or more of benzene, toluene, xylene and trimethylbenzene.
5. The method for removing water and chloride ions in fluoroethylene carbonate according to claim 1 or 2, wherein the amount of the alkaline drying agent added in step (1) is 5-20% by mass of fluoroethylene carbonate.
6. The method for removing water and chloride ions in fluoroethylene carbonate according to claim 5, wherein the amount of the alkaline drying agent added in step (1) is 10-15% by mass of fluoroethylene carbonate.
7. The method for removing water and chloride ions in fluoroethylene carbonate according to claim 1, wherein the fluoroethylene carbonate crystal product obtained in step (3) is washed 1 time with anhydrous dimethyl carbonate, and then blown with dry nitrogen for 0.5 hour, after blowing, the crystal is transferred to a storage tank, and when the temperature is recovered to be higher than 23 ℃, the crystal is melted into liquid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110990393.5A CN113845507A (en) | 2021-08-26 | 2021-08-26 | Method for removing water and chloride ions in fluoroethylene carbonate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110990393.5A CN113845507A (en) | 2021-08-26 | 2021-08-26 | Method for removing water and chloride ions in fluoroethylene carbonate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113845507A true CN113845507A (en) | 2021-12-28 |
Family
ID=78976224
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110990393.5A Pending CN113845507A (en) | 2021-08-26 | 2021-08-26 | Method for removing water and chloride ions in fluoroethylene carbonate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113845507A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116284096A (en) * | 2023-05-19 | 2023-06-23 | 研峰科技(北京)有限公司 | Synthesis method of tri (tert-butoxy) silanol with ultralow chloride ion content |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101717389A (en) * | 2009-10-29 | 2010-06-02 | 张家港市华盛化学有限公司 | Disacidifying and dewatering method of fluoroethylene carbonate |
| CN103113344A (en) * | 2012-09-26 | 2013-05-22 | 中国海洋石油总公司 | Purification method of high-purity fluoroethylene carbonate |
| CN105801554A (en) * | 2016-04-29 | 2016-07-27 | 河南省法恩莱特新能源科技有限公司 | Purification method of high-purity fluoroethylene carbonate |
| CN106810527A (en) * | 2017-01-06 | 2017-06-09 | 淮安瀚康新材料有限公司 | A kind of preparation method of fluoro ethylene carbonate with high purity |
| CN110878078A (en) * | 2019-10-12 | 2020-03-13 | 湖北省宏源药业科技股份有限公司 | Method for preparing electronic-grade fluoroethylene carbonate through fractional crystallization |
-
2021
- 2021-08-26 CN CN202110990393.5A patent/CN113845507A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101717389A (en) * | 2009-10-29 | 2010-06-02 | 张家港市华盛化学有限公司 | Disacidifying and dewatering method of fluoroethylene carbonate |
| CN103113344A (en) * | 2012-09-26 | 2013-05-22 | 中国海洋石油总公司 | Purification method of high-purity fluoroethylene carbonate |
| CN105801554A (en) * | 2016-04-29 | 2016-07-27 | 河南省法恩莱特新能源科技有限公司 | Purification method of high-purity fluoroethylene carbonate |
| CN106810527A (en) * | 2017-01-06 | 2017-06-09 | 淮安瀚康新材料有限公司 | A kind of preparation method of fluoro ethylene carbonate with high purity |
| CN110878078A (en) * | 2019-10-12 | 2020-03-13 | 湖北省宏源药业科技股份有限公司 | Method for preparing electronic-grade fluoroethylene carbonate through fractional crystallization |
Non-Patent Citations (2)
| Title |
|---|
| 宋晓莉等: "结晶控制法提纯碳酸亚乙烯酯的研究", 《电源技术》 * |
| 朱兵峰等: "水分去除的方法及其在药物合成中的应用", 《中国医药工业杂志》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116284096A (en) * | 2023-05-19 | 2023-06-23 | 研峰科技(北京)有限公司 | Synthesis method of tri (tert-butoxy) silanol with ultralow chloride ion content |
| CN116284096B (en) * | 2023-05-19 | 2023-09-19 | 研峰科技(北京)有限公司 | Synthesis method of tri (tert-butoxy) silanol with ultralow chloride ion content |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109941982B (en) | Purification method of lithium difluorophosphate | |
| CN109941978B (en) | Method for preparing ammonium bifluorosulfonamide and alkali metal salt of bifluorosulfonamide | |
| CN107055574A (en) | A kind of method of purification of lithium hexafluoro phosphate | |
| CN111573639A (en) | Method for preparing lithium bis (fluorosulfonyl) imide by using organic metal lithium reagent | |
| CN113845507A (en) | Method for removing water and chloride ions in fluoroethylene carbonate | |
| CN111925352A (en) | Method for synthesizing vinyl sulfate | |
| CN105801554A (en) | Purification method of high-purity fluoroethylene carbonate | |
| CN115231532A (en) | Preparation method and application of lithium bis (fluorosulfonyl) imide | |
| CN112739651B (en) | Method for preparing lithium fluorosulfonate by using organic metal lithium reagent | |
| CN112457266A (en) | Valsartan mother liquor recovery method | |
| CN112897494B (en) | Synthesis process and synthesis device of lithium difluorophosphate | |
| CN105037394A (en) | Preparing method for high-purity latamoxef sodium | |
| WO2016202252A1 (en) | Method for synthesizing d-para-hydroxyphenylglycine methyl ester | |
| CN104877167B (en) | The method that adjuvant used lithium chloride recycles in polyphenylene sulfide resin production process | |
| WO2024040906A1 (en) | Method for recycling lithium-ion battery electrolyte | |
| CN114573006B (en) | Method for purifying and recovering lithium by-product lithium-containing crude sodium sulfate in lithium extraction process of nickel cobalt lithium manganate anode material recovery | |
| CN116253295A (en) | Preparation method of ultra-pure semiconductor grade sulfuric acid | |
| CN116216688A (en) | Preparation method of lithium difluorophosphate | |
| CN113636999B (en) | Water removal and crystallization method of vinylene carbonate | |
| CN102498106A (en) | Process for the destillative purification of fluoroethylene carbonate | |
| CN103964409A (en) | Manufacturing method for high-purity LiPF6 | |
| CN113845506A (en) | Dynamic crystallization purification method of ethylene carbonate | |
| CN114014835A (en) | Glycolide purification process | |
| CN114195756A (en) | Method for removing anionic impurities and moisture in methylene methanedisulfonate | |
| JPS5918377B2 (en) | Purification method of sorbic acid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |