CN112159340A - Preparation method of hydroxyethyl sulfonic acid - Google Patents
Preparation method of hydroxyethyl sulfonic acid Download PDFInfo
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- CN112159340A CN112159340A CN202011086518.3A CN202011086518A CN112159340A CN 112159340 A CN112159340 A CN 112159340A CN 202011086518 A CN202011086518 A CN 202011086518A CN 112159340 A CN112159340 A CN 112159340A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C303/00—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
- C07C303/02—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/0093—Microreactors, e.g. miniaturised or microfabricated reactors
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C303/00—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
- C07C303/42—Separation; Purification; Stabilisation; Use of additives
- C07C303/44—Separation; Purification
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Abstract
The invention relates to a preparation method of isethionic acid, which comprises the following steps: (1) a pre-reaction stage; (2) deepening the reaction stage; (3) desalting treatment; (4) carrying out normal pressure distillation treatment; (5) decolorizing treatment and the like. The method changes the adding mode of the raw material hydrochloric acid, inhibits the reaction movement blockage of the traditional hydrochloric acid adding mode through the pre-reaction of the dilute hydrochloric acid and the secondary deepening reaction of the HCl gas, improves the conversion rate of the sodium isethionate, and greatly reduces the cost through recycling the hydrogen chloride and the sodium chloride.
Description
Technical Field
The invention relates to the technical field of organic product synthesis, in particular to a preparation method of isethionic acid.
Background
Hydroxyethyl sulfonic acid (HOCH)2CH2SO3H, ITA for short), is a compound having a strongly reactive hydroxyl group and a sulfonic acid group, and the content of industrial products is usually 70 to 80%, and due to the presence of the hydroxyl group in the structure, it has good water solubility, and is soluble in methanol, ethanol, acetone, etc., but insoluble in benzene, ethyl acetate, chloroform, etc. As an important organic intermediate, isethionic acid and its salts are useful as a raw material for a low-irritant surfactant, a reactive monomer, an aqueous lubricant, an antirust agent, an antibacterial agent, a local anesthetic, and the like, in addition to a brazing bath additive, a medical raw material, and a food additive.
At present, the laboratory synthesis method of the isethionic acid is various, but the industrial application is more widely applied to only two methods: the EO process and the mercaptoethanol/hydrogen peroxide oxidation process. The EO method mainly adopts sodium isethionate obtained by the reaction of ethylene oxide and sodium bisulfite, and obtains the isethionic acid by desalting treatment, and the process has the advantages of easily obtained raw materials and high reaction yield. However, the EO process often requires a higher hydrochloric acid concentration and sodium chloride impurities, and the obtained isethionic acid is not of high purity without subsequent treatment. In order to improve the purity of isethionic acid, in US4499028 alkali metal isethionate is mixed with anhydrous hydrochloric acid or concentrated hydrochloric acid solution to form isethionic acid in solution, which reduces the impurity content of the product isethionic acid by subsequent crystallization and filtration to remove sodium chloride and distillation under reduced pressure to remove excess hydrochloric acid, but this procedure is cumbersome and costly.
The mercaptoethanol/hydrogen peroxide oxidation process is a process for producing sulfonic acid by oxidizing mercaptan with hydrogen peroxide, and compared with the EO process, the reaction has a series of advantages: mild reaction conditions, low energy consumption, simple production process and water as a byproduct. In the US4987250, the synthesis of isethionic acid by reaction of beta-mercaptoethanol with hydrogen peroxide is disclosed, but the reaction process is not easy to control, the hydrogen peroxide concentration used initially cannot be too high, the amount of hydrogen peroxide to be added is strictly controlled, and if the control is not good, the yield and purity of the target product are not stable. Patent CN 110746326A discloses a method for continuously producing hydroxyethyl sulfonic acid by using a microchannel reactor, which is used for avoiding raw material H2O2Oxygen generated by decomposition accumulates in the reactor, reducing H2O2Control of concentration is required, but costs and scale are correspondingly limited.
In general, the prior synthesis processes of the isethionic acid have different advantages and disadvantages, and particularly have the disadvantages of cost, process operability, raw material utilization rate and comprehensive utilization of resources. Aiming at reducing environmental pollution, improving the utilization rate of raw materials and reducing cost, the invention provides a preparation method of isethionic acid so as to meet the increasingly developed market demand of isethionic acid.
Disclosure of Invention
Based on the defects of the prior art, the invention provides a preparation method of isethionic acid, which comprises the following specific steps:
(1) a pre-reaction stage: adding a certain amount of sodium isethionate, a recovered dilute hydrochloric acid solution and purified water into a reaction kettle, and fully stirring for pre-reaction;
(2) a deepening reaction stage: putting a certain amount of recovered sodium chloride and purified water into a generation kettle, stirring and completely dissolving to form a sodium chloride aqueous solution, slowly dripping concentrated sulfuric acid into the sodium chloride aqueous solution to generate hydrogen chloride gas, and introducing the hydrogen chloride gas into the reaction kettle in the step (1) to carry out a deepening reaction;
(3) desalting treatment: filtering the solution after the deepening reaction in the reaction kettle in the step (2) to recover sodium chloride, and using the sodium chloride as a raw material in the generation kettle in the step (2);
(4) atmospheric distillation treatment: distilling the filtrate obtained by desalting in the step (3) at normal pressure to remove residual HCl, and absorbing HCl by purified water to obtain the recovered dilute hydrochloric acid used as a raw material for pre-reaction in the step (1);
(5) and (3) decoloring treatment: and (4) decoloring the material distilled under normal pressure in the step (4) by using activated carbon and distilling under reduced pressure to remove redundant water, thus obtaining the hydroxyethyl sulfonic acid product.
Further, the pre-reaction time in the step (1) is 30-60 min.
Further, the deepening reaction time in the step (2) is 3-6 h.
Further, the temperature in the generation kettle is controlled to be 30-50 ℃ in the step (2).
Further, the temperature of the deepening reaction in the reaction kettle is controlled to be 60-70 ℃ in the step (2).
Further, the distillation treatment is performed at a temperature of 90 ℃ under normal pressure in the step (4) to remove residual HCl.
Further, desalting the residual solution subjected to the in-kettle reaction in the step (2) to obtain a by-product sodium sulfate.
Compared with the EO method in the prior art, the invention only needs to adopt dilute hydrochloric acid with lower concentration in the pre-reaction stage, and fully utilizes HCl obtained by normal pressure distillation treatment for secondary deepening reaction, so that the reaction of the raw material sodium isethionate and HCl is more complete, thereby effectively avoiding the occurrence of the condition that the reaction movement is hindered due to the absence of sodium isethionate participating in the reaction and sodium chloride which cannot be separated out in time in the prior EO method by adding concentrated hydrochloric acid once, and improving the conversion rate of sodium isethionate. Compared with a mercaptoethanol/hydrogen peroxide oxidation method, the method has the advantages of simple raw materials, easier control, less side reaction, and greatly reduced generation cost due to the cyclic recycling of HCl and NaCl in the reaction process.
The invention has the following beneficial effects: (1) the equipment requirement is simple, a micro-channel reactor is not needed, and the operation process is simple; the production investment is also greatly reduced. (2) High-pressure and high-temperature reaction is avoided, hydrochloric acid with high concentration is not needed, a catalyst is not needed, the product purity is high, and the safety is greatly improved. (3) The hydrogen chloride and the sodium chloride in the production process of the hydroxyethyl sulfonic acid are recycled, so that the production cost can be greatly reduced while the conversion rate of raw materials is ensured. (4) The byproduct sodium sulfate is sold as a product, thereby reducing the emission of pollutants and reducing the production cost.
Drawings
FIG. 1 is a flow chart of the process for preparing isethionic acid according to the invention.
Detailed Description
The following examples illustrate specific aspects of the invention and are not intended to limit the scope of the invention in any respect and should not be construed as limiting the scope of the invention. These examples are merely illustrative and should not be construed as limiting the scope of the claimed subject matter based on the present disclosure.
Example 1
A preparation method of hydroxyethyl sulfonic acid comprises the following steps:
(1) a pre-reaction stage: 2kg of sodium isethionate, 3kg of recycled dilute hydrochloric acid solution and a certain amount of purified water are added into a reaction kettle, and the mixture is fully stirred and pre-reacted for 30 min;
(2) a deepening reaction stage: a certain amount of recovered sodium chloride and purified water are put into a generation kettle, and are stirred to be completely dissolved to form a sodium chloride aqueous solution. Slowly dripping concentrated sulfuric acid into a sodium chloride aqueous solution, controlling the temperature in a generation kettle to be 30 ℃, introducing generated hydrogen chloride gas into the reaction kettle in the step (1) for a deepening reaction, controlling the reaction temperature to be 60 ℃, stirring for reacting for 6 hours, ensuring that sodium isethionate and hydrogen chloride are fully reacted, and keeping the amount of water existing in the reaction as low as possible so as to facilitate the removal of sodium chloride;
(3) desalting treatment: filtering the solution after the deepening reaction in the reaction kettle to recover sodium chloride which is used as the raw material in the generation kettle in the step (2);
(4) atmospheric distillation treatment: distilling the filtrate obtained by desalting in the step (3) at 90 ℃ under normal pressure to remove residual HCl, and absorbing the HCl by purified water to obtain the recovered dilute hydrochloric acid used as a raw material for pre-reaction in the step (1);
(5) and (3) decoloring treatment: and (4) decoloring the material distilled under normal pressure in the step (4) by using activated carbon and distilling under reduced pressure to remove redundant water, thus obtaining the hydroxyethyl sulfonic acid product.
Example 2
A preparation method of hydroxyethyl sulfonic acid comprises the following steps:
(1) a pre-reaction stage: 2.5kg of sodium isethionate, 3.85kg of recycled dilute hydrochloric acid solution and a certain amount of purified water are added into a reaction kettle, and the mixture is fully stirred and pre-reacted for 30 min;
(2) a deepening reaction stage: a certain amount of recovered sodium chloride and purified water are put into a generation kettle, and are stirred to be completely dissolved to form a sodium chloride aqueous solution. Slowly dripping concentrated sulfuric acid into a sodium chloride aqueous solution, controlling the temperature in a generation kettle to be 50 ℃, introducing generated hydrogen chloride gas into the reaction kettle in the step (1) for a deepening reaction, controlling the reaction temperature to be 70 ℃, stirring for reacting for 3 hours, ensuring that sodium isethionate and hydrogen chloride fully react, and keeping the amount of water existing in the reaction as low as possible so as to facilitate the removal of sodium chloride;
(3) desalting treatment: filtering the solution after the deepening reaction in the reaction kettle to recover sodium chloride which is used as the raw material in the generation kettle in the step (2);
(4) atmospheric distillation treatment: distilling the filtrate obtained by desalting in the step (3) at 90 ℃ under normal pressure to remove residual HCl, and absorbing the HCl by purified water to obtain the recovered dilute hydrochloric acid used as a raw material for pre-reaction in the step (1);
(5) and (3) decoloring treatment: and (4) decoloring the material distilled under normal pressure in the step (4) by using activated carbon and distilling under reduced pressure to remove redundant water, thus obtaining the hydroxyethyl sulfonic acid product.
Example 3
A preparation method of hydroxyethyl sulfonic acid comprises the following steps:
(1) a pre-reaction stage: 1.8kg of sodium isethionate, 0.96kg of recycled dilute hydrochloric acid solution and a certain amount of purified water are added into a reaction kettle, and the mixture is fully stirred and pre-reacted for 30 min;
(2) a deepening reaction stage: a certain amount of recovered sodium chloride and purified water are put into a generation kettle, and are stirred to be completely dissolved to form a sodium chloride aqueous solution. Slowly dripping concentrated sulfuric acid into a sodium chloride aqueous solution, controlling the temperature in a generation kettle to be 40 ℃, introducing generated hydrogen chloride gas into the reaction kettle in the step (1) for a deepening reaction, controlling the reaction temperature to be 65 ℃, stirring for reacting for 5 hours, ensuring that sodium isethionate and hydrogen chloride are fully reacted, and keeping the amount of water existing in the reaction as low as possible so as to facilitate the removal of sodium chloride;
(3) desalting treatment: filtering the solution after the deepening reaction in the reaction kettle to recover sodium chloride which is used as the raw material in the generation kettle in the step (2);
(4) atmospheric distillation treatment: distilling the filtrate obtained by desalting in the step (3) at 90 ℃ under normal pressure to remove residual HCl, and absorbing the HCl by purified water to obtain the recovered dilute hydrochloric acid used as a raw material for pre-reaction in the step (1);
(5) and (3) decoloring treatment: and (4) decoloring the material distilled under normal pressure in the step (4) by using activated carbon and distilling under reduced pressure to remove redundant water, thus obtaining the hydroxyethyl sulfonic acid product.
Comparative example 1
According to the preparation method of the patent US4499028 and the reaction molar ratio in the example 1, hydrochloric acid is added in one step in a concentrated hydrochloric acid mode, and after 6 hours of one-time reaction, filtration desalination and treatment of a normal pressure distillation part and subsequent decolorization and other treatments are carried out to obtain the hydroxyethyl sulfonic acid.
Comparative example 2
Oxalic acid is adopted to replace hydrochloric acid, and according to the reaction molar ratio in the embodiment 1, the oxalic acid is added at one time, and after 6 hours of primary reaction, filtration desalination, treatment at normal pressure distillation and subsequent decolorization and other treatments are carried out to obtain the hydroxyethyl sulfonic acid.
The isethionic acid obtained in examples 1-3 and comparative examples 1-2 were subjected to High Performance Liquid Chromatography (HPLC) analysis to determine the relative amount of sodium isethionate therein for calculating the conversion of the starting material sodium isethionate. Test results show that the conversion rate of the sodium isethionate in the embodiment of the invention can reach about 92 percent, and the conversion rate in the comparative example 1 is only 83.2 percent. In comparative example 2, although the organic acid is used to replace hydrochloric acid, the crystallinity of the organic acid salt is fully utilized to improve the conversion rate, and the final conversion rate can reach 91.6%, the cost of the organic acid is far higher than that of the hydrochloric acid, and the hydrochloric acid can be recycled, so that the cost is greatly reduced while the conversion rate is improved.
In summary, according to the preparation method of isethionic acid, the diluted hydrochloric acid obtained by atmospheric distillation is fully utilized through the secondary deepening reaction, and the sodium isethionate and HCl are reacted more fully through the secondary trace deepening reaction, so that the precipitation of sodium chloride is ensured, the reaction movement resistance is reduced, and the conversion rate of the raw materials is improved.
The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner; the present invention may be readily implemented by those of ordinary skill in the art as illustrated in the accompanying drawings and described above; however, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the scope of the invention as defined by the appended claims; meanwhile, any changes, modifications, and evolutions of the equivalent changes of the above embodiments according to the actual techniques of the present invention are still within the protection scope of the technical solution of the present invention.
Claims (7)
1. A preparation method of isethionic acid comprises the following specific steps:
(1) a pre-reaction stage: adding a certain amount of sodium isethionate, a recovered dilute hydrochloric acid solution and purified water into a reaction kettle, and fully stirring for pre-reaction;
(2) a deepening reaction stage: putting a certain amount of recovered sodium chloride and purified water into a generation kettle, stirring and completely dissolving to form a sodium chloride aqueous solution, slowly dripping concentrated sulfuric acid into the sodium chloride aqueous solution to generate hydrogen chloride gas, and introducing the hydrogen chloride gas into the reaction kettle in the step (1) to carry out a deepening reaction;
(3) desalting treatment: filtering and recovering the solution obtained after the deepening reaction in the reaction kettle in the step (2) to obtain the recovered sodium chloride, and using the recovered sodium chloride as the raw material in the generation kettle in the step (2);
(4) atmospheric distillation treatment: distilling the filtrate obtained by desalting in the step (3) at normal pressure to remove residual HCl in the filtrate, and absorbing the HCl by purified water to obtain the recovered dilute hydrochloric acid which is used as a raw material for pre-reaction in the step (1);
(5) and (3) decoloring treatment: and (4) decoloring the material distilled under normal pressure in the step (4) by using activated carbon and distilling under reduced pressure to remove redundant water, thus obtaining the hydroxyethyl sulfonic acid product.
2. The process for producing isethionic acid according to claim 1, wherein the pre-reaction time in step (1) is in the range of 30 to 60 min.
3. The process for preparing isethionic acid according to claim 1, wherein the time for the deepening reaction in step (2) is 3 to 6 hours.
4. The process for producing isethionic acid according to claim 1, wherein in step (2), the temperature in the generator tank is controlled to 30 to 50 ℃.
5. The process for producing isethionic acid according to claim 1, wherein in step (2), the temperature of the deepening reaction in the reaction tank is controlled to 60 to 70 ℃.
6. The process for producing isethionic acid according to claim 1, wherein said atmospheric distillation in step (5) is carried out at a temperature of 90 ℃ under atmospheric pressure to remove residual HCl.
7. The process for producing isethionic acid according to claim 1, wherein the residual solution from the kettle reaction in step (2) is desalted to obtain sodium sulfate as a by-product.
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| CN202011086518.3A CN112159340A (en) | 2020-10-12 | 2020-10-12 | Preparation method of hydroxyethyl sulfonic acid |
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| CN202011086518.3A CN112159340A (en) | 2020-10-12 | 2020-10-12 | Preparation method of hydroxyethyl sulfonic acid |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115572246A (en) * | 2022-09-30 | 2023-01-06 | 湖北源洹实业投资有限公司 | Process for preparing benzenesulfonic acid by taking hydrogen chloride gas as acidification reagent |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4499028A (en) * | 1982-09-07 | 1985-02-12 | Witco Chemical Corporation | Preparation of isethionic acid |
| US4696773A (en) * | 1986-07-07 | 1987-09-29 | Johnson & Johnson Baby Products Company | Process for the preparation of isethionic acid |
| JPH0366659A (en) * | 1989-08-04 | 1991-03-22 | Nisso Yuka Kogyo Kk | Production of isethionic acid |
| CN1067051A (en) * | 1991-05-18 | 1992-12-16 | 成都市郫县电子精细化工厂 | The preparation method of hydroxy alkyl sulfonic acid |
| CN105585513A (en) * | 2016-01-22 | 2016-05-18 | 中国石油大学(华东) | Preparation method of sodium 3-chloro-2-hydroxy propanesulfonate |
-
2020
- 2020-10-12 CN CN202011086518.3A patent/CN112159340A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4499028A (en) * | 1982-09-07 | 1985-02-12 | Witco Chemical Corporation | Preparation of isethionic acid |
| US4696773A (en) * | 1986-07-07 | 1987-09-29 | Johnson & Johnson Baby Products Company | Process for the preparation of isethionic acid |
| JPH0366659A (en) * | 1989-08-04 | 1991-03-22 | Nisso Yuka Kogyo Kk | Production of isethionic acid |
| CN1067051A (en) * | 1991-05-18 | 1992-12-16 | 成都市郫县电子精细化工厂 | The preparation method of hydroxy alkyl sulfonic acid |
| CN105585513A (en) * | 2016-01-22 | 2016-05-18 | 中国石油大学(华东) | Preparation method of sodium 3-chloro-2-hydroxy propanesulfonate |
Non-Patent Citations (3)
| Title |
|---|
| 成都市教育局: "《化学第四册 》", 30 November 1979, 四川人民出版社 * |
| 李建颖主编: "《食品添加剂速查手册》", 30 November 2017, 南开大学出版社 * |
| 衷友泉等: "《无机化学》", 31 July 2020, 华中科技大学出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115572246A (en) * | 2022-09-30 | 2023-01-06 | 湖北源洹实业投资有限公司 | Process for preparing benzenesulfonic acid by taking hydrogen chloride gas as acidification reagent |
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