CN104829445A - Method for producing aqueous solution of glycolic acid - Google Patents
Method for producing aqueous solution of glycolic acid Download PDFInfo
- Publication number
- CN104829445A CN104829445A CN201510225410.0A CN201510225410A CN104829445A CN 104829445 A CN104829445 A CN 104829445A CN 201510225410 A CN201510225410 A CN 201510225410A CN 104829445 A CN104829445 A CN 104829445A
- Authority
- CN
- China
- Prior art keywords
- aqueous solution
- glycolic acid
- distillation column
- acid aqueous
- content
- 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
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/09—Preparation of carboxylic acids or their salts, halides or anhydrides from carboxylic acid esters or lactones
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
- C07C51/44—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation by distillation
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for producing an aqueous solution of glycolic acid, and mainly solves the problems of low yield and low product purity in the prior art. The method for producing the aqueous solution of glycolic acid is as below: conducting hydrolysis reaction on the raw materials of methyl glycolate and water in a fixed bed reactor under autocatalysis conditions without a catalyst at the reaction temperature of 60-80 DEG C, atmospheric pressure and liquid hourly space velocity of 0.4-3.0 / h; sending the fixed bed reactor outlet products into a reaction distillation column; and continuously extracting methanol and water condensate from the top of the reaction distillation column. The technical scheme of continuous extraction of aqueous solution of glycolic acid can solve the above problems, and can be applied to the production of aqueous solution of glycolic acid.
Description
Technical field
The present invention relates to a kind of production method of glycolic acid aqueous solution.
Background technology
Along with the worsening shortages of petroleum resources, carry out and based on the C1 chemical industry of Sweet natural gas and coal-based feedstocks, China is had important practical significance, in the last few years, coal based synthetic gas has obtained remarkable achievement through prepared by dimethyl oxalate plus hydrogen methyl glycolate technology, and the product chain in exploitation methyl glycolate downstream becomes the focus and emphasis of this area research further.
Oxyacetic acid is in the past mainly for the manufacture of boiler descaling agent, clean-out system etc.Be widely used as makeup and pharmaceuticals in recent years, its raw material as polyglycolic acid also receives publicity.Now commercially available oxyacetic acid product comprises 70% glycollic acid solution and oxyacetic acid crystal.Methoxyacetic acid containing certain content in technical grade 70% glycollic acid solution and diglycollic acid, the product that part manufacturer production goes out contains a certain amount of sodium-chlor, the oxyacetic acid crystal obtained thus also containing a small amount of diglycollic acid or chloride ion impurities, thus have impact on quality and the range of application of product.Along with the purposes of oxyacetic acid is more and more extensive, require also more and more higher to the purity of product and impurity.
The reaction that oxyacetic acid is prepared in methyl glycolate hydrolysis is as follows:
OHCH
2COOCH
3+H
2O→OHCH
2COOH+CH
3OH
As can be seen from the above equation, methyl glycolate hydrolysis can generate oxyacetic acid and methyl alcohol, from existing document, adopts batch tank reactor, by steps such as hydrolysis, concentrated and crystallizations, can obtain oxyacetic acid product (CN103508878A); How realizing operate continuously, reduce ion exchange resin swelling, extending catalyst work-ing life, is new demand and the difficult point of research at present.
At present, the production technique of industrial oxyacetic acid mainly adopts Mono Chloro Acetic Acid hydrolysis method and formaldehyde carbonyl process.
(1) Mono Chloro Acetic Acid hydrolysis method: oxyacetic acid is prepared in the sodium hydroxide catalyzed hydrolysis of Mono Chloro Acetic Acid, and yield can reach more than 95%, and quality product mark can reach more than 98%.Less demanding to reaction raw materials of this method, the impurity dichloro acetic acid in raw material is also hydrolyzed to oxyacetic acid, and Mono Chloro Acetic Acid toxicity is large, and corrodibility is strong, is unfavorable for environmental protection, and containing chlorion in product.
Patent CN103450006A discloses and adopts Monochloro Acetic Acid to produce the technique of oxyacetic acid, by the technique of production of chloroacetic acid oxyacetic acid, comprises with 1-Mono Chloro Acetic Acid and sodium carbonate through being hydrolyzed, concentrating, lower the temperature, get rid of the roughing process expecting to obtain solid alcohol acid crude.The mode of the method employing secondary crystal removes the chlorion in product.
(2) formaldehyde carbonyl process: this method is current external topmost industrial method.Formaldehyde, CO and water is synthesizing of glycolate under the effect of catalyzer.Under 90MPa, the yield of oxyacetic acid is close to 90%, and the method raw materials cost is low, but high to equipment requirements, product separation, refining complexity.
Patent CN102531883A discloses a kind of method of continuous seepage oxyacetic acid, adopt falling film reactor, liquid phase medium containing formaldehyde or derivatives thereof and the gas phase media containing CO react and generate oxyacetic acid under an acidic catalyst effect, in the method, carbonyl reaction carries out in the falling film reactor that a large amount of fiber medium is housed, and can realize continuous seepage.DuPont (US2152852) and Chevron (US3911003) all adopts an acidic catalyst catalysis formaldehyde and CO carbonylation reaction.
Summary of the invention
Technical problem to be solved by this invention is the problem that in prior art, yield is lower, product purity is lower, catalyst life is shorter, provides a kind of production method of new glycolic acid aqueous solution.The method is used for, in the production of glycolic acid aqueous solution, having the advantage that yield is higher, product purity is higher.
For solving the problem, the technical solution used in the present invention is as follows: a kind of production method of glycolic acid aqueous solution, with methyl glycolate and water for raw material, in fixed-bed reactor catalyst-free autocatalysis condition under, temperature of reaction be 60 ~ 80 DEG C, pressure is normal pressure, liquid hourly space velocity is 0.4 ~ 3.0h
-1under to be hydrolyzed reaction, fixed-bed reactor outlets products enters reactive distillation column, the continuous extraction methyl alcohol of reactive distillation column overhead and water-cooled lime set, the continuous extraction glycolic acid aqueous solution of tower reactor; Wherein, the operational condition of reactive distillation column is: pressure is 10 ~ 100kPa, bottom temperature is 65 ~ 100 DEG C, tower top temperature is 45 ~ 65 DEG C, number of theoretical plate is 15 ~ 30 pieces, reflux ratio is 0.5 ~ 3, and liquid hourly space velocity is 0.4 ~ 3.0h-1.
In technique scheme, preferably, in described glycolic acid aqueous solution, the content of oxyacetic acid is 15 ~ 25wt%, and methyl glycolate content is 0 ~ 0.5wt%, and methanol content is 0 ~ 0.5wt%, and water-content is 75 ~ 85wt%.
In technique scheme, preferably, load inertia weighting material in described fixed-bed reactor, described inertia weighting material includes but are not limited to Al2O3 inert ceramic balls, at least one in quartz sand, glass spring.
In technique scheme, preferably, the mol ratio of described methyl glycolate and water is 1:5 ~ 30.
In technique scheme, preferably, methyl glycolate content 10 ~ 25wt% in described fixed-bed reactor outlets products, oxyacetic acid content 5 ~ 15wt%, methanol content 5 ~ 15wt%, water 50 ~ 80wt%.
In technique scheme, preferably, in described reactive distillation column, catalyst loading is in the centre of reactive distillation column, filler is seated in two sections of reactive distillation column, described catalyzer is acidic ion exchange resin, includes but are not limited at least one in 001*7 type, 001*14.5 type, D-72 type, NKC-9 type, Amberlyst-35 type; Described filler includes but are not limited at least one in θ ring, SM700, SM350, SM500.
In technique scheme, preferably, described reactive distillation column overhead methanol content is 70 ~ 99wt%, and water-content is 1 ~ 30wt%.
The self-catalyzed reaction formula of carrying out in fixed-bed reactor described in the present invention is:
The reaction formula carried out in reactive distillation column is:
The invention provides the method for a kind of methyl glycolate hydrolysis oxyacetic acid processed, comprise methyl glycolate fixed bed autocatalysis technique and reactive distillation process, wherein, adopt fixed bed reaction technique, under autocatalysis condition, reaction raw materials methyl glycolate is made to carry out pre-reaction, adopt the method for reactive distillation to be coupled with rectification process by hydrolysis reaction simultaneously, thus by-product carbinol is removed from tower top, methyl glycolate is transformed completely, and technical process is simple, easy to operate, oxyacetic acid impurity is few, improves hydrolysis reaction transformation efficiency and selectivity.The present invention to obtain in oxyacetic acid not containing methoxyacetic acid and formic acid, purity and yield higher.Methyl glycolate transformation efficiency is greater than 95%, and oxyacetic acid selectivity is greater than 95%, and total recovery is greater than 90%.The advantage that the method has continuously is convenient, production efficiency is high, production cost is low, product impurity is few, yield is high, achieves good technique effect.
Below by embodiment, the invention will be further elaborated, but be not limited only to the present embodiment.
Embodiment
[embodiment 1]
The technique that the present invention produces oxyacetic acid by methyl glycolate comprises the steps:
1) by inertia Al
2o
3porcelain ball loads in fixed-bed reactor, methyl glycolate and water is mixed with the ratio of mol ratio 1:10, enters fixed-bed reactor, air speed 2.5h through pump
-1, temperature of reaction 70 DEG C, reaction pressure normal pressure, fixed bed Export Ethanol acid methyl ester conversion rate 30.4%, oxyacetic acid selectivity 100%, fixed bed outlets products, through surge tank, enters continuous reaction rectification device through pump, in continuous reaction rectification, filler is θ ring, and catalyzer is 001*7, and liquid hourly space velocity is 2.5h
-1number of theoretical plate 25, feed entrance point is the 10th piece of theoretical stage place, and conversion zone is 8th ~ 16 pieces of theoretical stage places, reflux ratio 1:1, vacuum tightness 50kPa, tower reactor reboiler temperature 80 DEG C, in reaction process, tower top discharging pipeline continues extraction recovery methanol condensed liquid, and tower reactor maintains extraction product ethanol acid solution, final methyl glycolate transformation efficiency 99.2%, oxyacetic acid selectivity 98.9%.
[embodiment 2]
According to the condition described in embodiment 1 and step, change the kind of catalyzer in continuous reaction rectification device, specifically comprise 001*7,001*14.5, D-72, NKC-9, Amberlyst 35 etc., methyl glycolate transformation efficiency is 99.0%, and oxyacetic acid selectivity is 99%.
[embodiment 3]
According to the condition described in embodiment 1 and step, reactive distillation column adopts filler to be SM700, SM350, SM500 mixed fillers, and the volume ratio of SM700, SM350, SM500 is 1:1:1, final methyl glycolate transformation efficiency 100%, oxyacetic acid selectivity 96.7%.
[embodiment 4]
According to the condition described in embodiment 1 and step, feed ethanol acid methyl esters and water are mixed with the ratio of mol ratio 1:5, enters fixed-bed reactor through pump, final methyl glycolate transformation efficiency 96%, oxyacetic acid selectivity 90%.
[embodiment 5]
According to the condition described in embodiment 1 and step, feed ethanol acid methyl esters and water are mixed with the ratio of mol ratio 1:20, enters fixed-bed reactor through pump, final methyl glycolate transformation efficiency 100%, oxyacetic acid selectivity 98.9%.
[embodiment 6]
According to the condition described in embodiment 1 and step, methyl glycolate and water are mixed with the ratio of mol ratio 1:10, enters fixed-bed reactor through pump, air speed 1.25h
-1, temperature of reaction 70 DEG C, reaction pressure normal pressure, fixed bed Export Ethanol acid methyl ester conversion rate 34.5%, oxyacetic acid selectivity 100%, final methyl glycolate transformation efficiency 98.5%, oxyacetic acid selectivity 99.1%.
[embodiment 7]
According to the condition described in embodiment 1 and step, methyl glycolate and water are mixed with the ratio of mol ratio 1:10, enters reactor through pump, air speed 1.25h
-1, temperature of reaction 60 DEG C, reaction pressure normal pressure, fixed bed Export Ethanol acid methyl ester conversion rate 32.4%, oxyacetic acid selectivity 100%, final methyl glycolate transformation efficiency 100%, oxyacetic acid selectivity 98.46%.
[embodiment 8]
According to the condition described in embodiment 1 and step, reactive distillation column working pressure is 30kPa, tower reactor temperature of reaction 65 DEG C, final methyl glycolate transformation efficiency 98.6%, oxyacetic acid selectivity 99.75%.
[embodiment 9]
According to the condition described in embodiment 1 and step, reactive distillation column working pressure is 100kPa, bottom temperature 101 DEG C, tower top temperature 64.3 DEG C, final methyl glycolate transformation efficiency 100%, oxyacetic acid selectivity 89%.
[embodiment 10]
According to the condition described in embodiment 1 and step, catalyzer is D-72, final methyl glycolate transformation efficiency 99%, oxyacetic acid selectivity 99%.
[embodiment 11]
According to the condition described in embodiment 1 and step, catalyzer is Amberlyst 35, final methyl glycolate transformation efficiency 99%, oxyacetic acid selectivity 99%.
[embodiment 12]
According to the condition described in embodiment 1 and step, catalyzer is 001*14.5, final methyl glycolate transformation efficiency 99%, oxyacetic acid selectivity 99%.
[embodiment 13]
According to the condition described in embodiment 1 and step, catalyzer is NKC-9, final methyl glycolate transformation efficiency 99%, oxyacetic acid selectivity 99%.
Claims (7)
1. a production method for glycolic acid aqueous solution, with methyl glycolate and water for raw material, in fixed-bed reactor catalyst-free autocatalysis condition under, temperature of reaction be 60 ~ 80 DEG C, pressure is normal pressure, liquid hourly space velocity is 0.4 ~ 3.0h
-1under to be hydrolyzed reaction, fixed-bed reactor outlets products enters reactive distillation column, the continuous extraction methyl alcohol of reactive distillation column overhead and water-cooled lime set, the continuous extraction glycolic acid aqueous solution of tower reactor; Wherein, the operational condition of reactive distillation column is: pressure is 10 ~ 100kPa, bottom temperature is 65 ~ 100 DEG C, tower top temperature is 45 ~ 65 DEG C, number of theoretical plate is 15 ~ 30 pieces, reflux ratio is 0.5 ~ 3, liquid hourly space velocity is 0.4 ~ 3.0h
-1.
2. the production method of glycolic acid aqueous solution according to claim 1, it is characterized in that the content of oxyacetic acid in described glycolic acid aqueous solution is 15 ~ 25wt%, methyl glycolate content is 0 ~ 0.5wt%, and methanol content is 0 ~ 0.5wt%, and water-content is 75 ~ 85wt%.
3. the production method of glycolic acid aqueous solution according to claim 1, it is characterized in that loading inertia weighting material in described fixed-bed reactor, described inertia weighting material includes but are not limited to Al
2o
3inert ceramic balls, at least one in quartz sand, glass spring.
4. the production method of glycolic acid aqueous solution according to claim 1, is characterized in that the mol ratio of described methyl glycolate and water is 1:5 ~ 30.
5. the production method of glycolic acid aqueous solution according to claim 1, is characterized in that methyl glycolate content 10 ~ 25wt% in described fixed-bed reactor outlets products, oxyacetic acid content 5 ~ 15wt%, methanol content 5 ~ 15wt%, water 50 ~ 80wt%.
6. the production method of glycolic acid aqueous solution according to claim 1, it is characterized in that in described reactive distillation column, catalyst loading is in the centre of reactive distillation column, filler is seated in two sections of reactive distillation column, described catalyzer is acidic ion exchange resin, includes but are not limited at least one in 001*7 type, 001*14.5 type, D-72 type, NKC-9 type, Amberlyst-35 type; Described filler includes but are not limited at least one in θ ring, SM700, SM350, SM500.
7. the production method of glycolic acid aqueous solution according to claim 1, it is characterized in that described reactive distillation column overhead methanol content is 70 ~ 99wt%, water-content is 1 ~ 30wt%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510225410.0A CN104829445A (en) | 2015-05-04 | 2015-05-04 | Method for producing aqueous solution of glycolic acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510225410.0A CN104829445A (en) | 2015-05-04 | 2015-05-04 | Method for producing aqueous solution of glycolic acid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104829445A true CN104829445A (en) | 2015-08-12 |
Family
ID=53807693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510225410.0A Pending CN104829445A (en) | 2015-05-04 | 2015-05-04 | Method for producing aqueous solution of glycolic acid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104829445A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105085227A (en) * | 2015-09-08 | 2015-11-25 | 上海华谊（集团）公司 | Method for producing glycolic acid solution |
| RU2610257C1 (en) * | 2015-11-19 | 2017-02-08 | Федеральное государственное автономное образовательное учреждение высшего образования "Национальный исследовательский Томский государственный университет" (ТГУ, НИ ТГУ) | Method for separating glycolic acid from mixed glyoxal disproportionation products |
| CN106478403A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that glycolic-aqueous mixtures are prepared by methyl glycollate |
| CN106478402A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that ethanol acid crystal is prepared by methyl glycollate |
| CN106478401A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that methyl glycollate prepares ethanol acid crystal |
| CN106478414A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that methyl glycollate prepares glycolic-aqueous mixtures |
| CN114057564A (en) * | 2021-12-09 | 2022-02-18 | 上海卓笙环保科技有限公司 | Method for hydrolyzing glycolate by taking carbonic acid system as traceless catalyst |
| CN114518418A (en) * | 2022-01-17 | 2022-05-20 | 内蒙古久泰新材料有限公司 | Quantitative detection method for content of organic carboxylic acid in cyclic lactide |
| CN115160122A (en) * | 2022-08-26 | 2022-10-11 | 东华工程科技股份有限公司 | Novel process for preparing glycollic acid by hydrolyzing methyl glycolate |
| CN115181019A (en) * | 2022-08-26 | 2022-10-14 | 东华工程科技股份有限公司 | Process for preparing electronic grade glycolic acid solution by hydrolyzing methyl glycolate |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103508878A (en) * | 2012-06-27 | 2014-01-15 | 上海浦景化工技术有限公司 | Method for preparing high-purity glycolic acid crystals from methyl glycolate |
| CN104177250A (en) * | 2014-09-16 | 2014-12-03 | 上海华谊（集团）公司 | Process for producing glycollic acid from methyl glycolate |
-
2015
- 2015-05-04 CN CN201510225410.0A patent/CN104829445A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103508878A (en) * | 2012-06-27 | 2014-01-15 | 上海浦景化工技术有限公司 | Method for preparing high-purity glycolic acid crystals from methyl glycolate |
| CN104177250A (en) * | 2014-09-16 | 2014-12-03 | 上海华谊（集团）公司 | Process for producing glycollic acid from methyl glycolate |
Non-Patent Citations (1)
| Title |
|---|
| 黄光晓等: "乙醇酸甲酯水解制备乙醇酸的反应动力学", 《天然气化工（C1化学与化工）》 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106478403A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that glycolic-aqueous mixtures are prepared by methyl glycollate |
| CN106478402A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that ethanol acid crystal is prepared by methyl glycollate |
| CN106478401A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that methyl glycollate prepares ethanol acid crystal |
| CN106478414A (en) * | 2015-08-28 | 2017-03-08 | 中国石油化工股份有限公司 | The method that methyl glycollate prepares glycolic-aqueous mixtures |
| CN105085227A (en) * | 2015-09-08 | 2015-11-25 | 上海华谊（集团）公司 | Method for producing glycolic acid solution |
| RU2610257C1 (en) * | 2015-11-19 | 2017-02-08 | Федеральное государственное автономное образовательное учреждение высшего образования "Национальный исследовательский Томский государственный университет" (ТГУ, НИ ТГУ) | Method for separating glycolic acid from mixed glyoxal disproportionation products |
| CN114057564A (en) * | 2021-12-09 | 2022-02-18 | 上海卓笙环保科技有限公司 | Method for hydrolyzing glycolate by taking carbonic acid system as traceless catalyst |
| CN114057564B (en) * | 2021-12-09 | 2023-10-03 | 上海卓笙环保科技有限公司 | Method for hydrolyzing glycollate based on carbonic acid system as traceless catalyst |
| CN114518418A (en) * | 2022-01-17 | 2022-05-20 | 内蒙古久泰新材料有限公司 | Quantitative detection method for content of organic carboxylic acid in cyclic lactide |
| CN114518418B (en) * | 2022-01-17 | 2024-03-22 | 内蒙古久泰新材料有限公司 | Quantitative detection method for organic carboxylic acid content in cyclic lactide |
| CN115160122A (en) * | 2022-08-26 | 2022-10-11 | 东华工程科技股份有限公司 | Novel process for preparing glycollic acid by hydrolyzing methyl glycolate |
| CN115181019A (en) * | 2022-08-26 | 2022-10-14 | 东华工程科技股份有限公司 | Process for preparing electronic grade glycolic acid solution by hydrolyzing methyl glycolate |
| CN115181019B (en) * | 2022-08-26 | 2024-03-19 | 东华工程科技股份有限公司 | Process for preparing electronic grade glycollic acid solution by methyl glycolate hydrolysis |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104829445A (en) | Method for producing aqueous solution of glycolic acid | |
| CN103641721B (en) | Energy-saving process for producing and separating dimethyl carbonate | |
| CN103524345B (en) | Product separation process for preparing methyl acrylate from methyl acetate | |
| CN107501042B (en) | Method for preparing isopropanol by hydrolyzing isopropyl acetate | |
| CN104592030A (en) | Method for synthesizing phthalate compounds | |
| CN104529763A (en) | Process and device for synthesizing ethyl formate with reactive distillation dividing wall column | |
| CN102134191B (en) | Process method for producing ethyl acetate by catalytic rectification | |
| CN106866366A (en) | Dihydroxylic alcohols or polyol impurities and the method for increasing production ethylene glycol in a kind of removal ethylene glycol | |
| CN101481293B (en) | Catalytic hydrolysis process for by-product methyl acetate of purified terephthalic acid production | |
| CN102690186A (en) | Methyl acetate hydrolysis partition reaction rectification column and operating method thereof | |
| CN103159591B (en) | Technique of synthesizing ethanol with acetic acid | |
| CN102850223A (en) | Method for synthesizing methylethyl carbonate | |
| CN103265429B (en) | Technical method for synthesizing methyl acetate | |
| CN108947774A (en) | A kind of method and device of separating isopropanol | |
| CN103361388A (en) | L-cyclic alkylamino acid synthesis method and medicinal composition containing L-cyclic alkylamino acid | |
| CN104892400A (en) | Intermittent reaction-continuous reaction rectification combined process for catalytic synthesis of oxalic acid | |
| CN109134258B (en) | Product separation process for preparing methyl glycolate by dimethyl oxalate hydrogenation | |
| CN104892389A (en) | Technique for preparing oxalic acid by performing continuous reaction rectification hydrolysis on dimethyl oxalate | |
| CN212076906U (en) | Side-line reaction type dioxolane production process device | |
| CN102120726B (en) | New preparation method of (2E)-2-cyano-3-(3,4-dihydroxy-5-nitrobenzene)-N,N-diethyl-2-acrylamide | |
| CN110818538A (en) | Na-NaOH/gamma-Al2O3Method for catalytic synthesis of anisole | |
| CN112479858A (en) | Methanol carbonylation enhanced reaction system and process with aldehyde recovery function | |
| CN103420800A (en) | Method for preparing dichloropropanol by catalyzing chlorination of glycerol through ionic liquids | |
| CN117886693B (en) | Synthesis method of 3-ethoxyethyl acrylate | |
| CN103232325A (en) | Method for preparing cyclohexanol from cyclohexene |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| EXSB | Decision made by sipo to initiate substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20150812 |