CN109694318A - The method for producing high purity ethanol acid - Google Patents
The method for producing high purity ethanol acid Download PDFInfo
- Publication number
- CN109694318A CN109694318A CN201710982580.2A CN201710982580A CN109694318A CN 109694318 A CN109694318 A CN 109694318A CN 201710982580 A CN201710982580 A CN 201710982580A CN 109694318 A CN109694318 A CN 109694318A
- Authority
- CN
- China
- Prior art keywords
- crystallizer
- crystal
- ethyl alcohol
- iii
- acid
- 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
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D9/00—Crystallisation
- B01D9/0004—Crystallisation cooling by heat exchange
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The present invention relates to a kind of methods for producing high purity ethanol acid, glycolic acid aqueous solution carries out crystallisation by cooling in crystallizer I, gained magma I obtains ethyl alcohol acid crystal I and crystalline mother solution I through being separated by solid-liquid separation, ethyl alcohol acid crystal I is washed, process units is discharged as product after drying, then crystalline mother solution I is concentrated, concentrate is sent again and carries out crystallisation by cooling into crystallizer II, gained magma II obtains ethyl alcohol acid crystal II and crystalline mother solution II through being separated by solid-liquid separation, ethyl alcohol acid crystal II is washed, process units is discharged as product after drying, crystalline mother solution II, which enters back into, carries out crystallisation by cooling in crystallizer III, gained magma obtains ethyl alcohol acid crystal III and crystalline mother solution III after being separated by solid-liquid separation, ethyl alcohol acid crystal III returns in crystallizer I or crystallizer II.The present invention solves the problems, such as that small crystal grain existing in the prior art, the easy moisture absorption, product purity is low, the rate of recovery is low, production energy consumption is high, can be used in the production of high purity ethanol acid.
Description
Technical field
The present invention relates to a kind of methods for producing high-purity glycolic.
Background technique
Glycolic, also known as hydroxyacetic acid are a kind of important chemical products and organic synthesis raw material, are widely used, can use
It is cleaned in metal, prepares fiber dyeing agent, adhesive etc., it can also be used in skin care item, for removing dead skin and fine hair, polymerize
Object is alternatively arranged as biodegradable material for medical industry.
Country's ethyl alcohol acid product is in the majority with glycolic acid aqueous solution at present, and the glycolic crystal product of high-purity is less, and produces
There are certain gaps with external product for product purity.As glycolic is in the continuous application of medical and beauty treatment industry, market is to high-purity
The demand of glycolic crystal product can be increasing, and existing glycolic crystal production method has certain deficiency, need to be into
One step is improved.
Chinese patent CN103508878A discloses a kind of method for preparing high purity ethanol acid crystal by methyl glycollate,
It is -10~15 DEG C that outlet temperature is crystallized in the program, and minimum crystallization temperature is only -10 DEG C, actually at this time in crystalline mother solution
Still there is quite a few glycolic not to be recovered, therefore the rate of recovery of glycolic is high not enough, that is, reduces the effect of crystallization process
Rate.
Chinese patent CN1625543A discloses a kind of manufacturing method of high-purity cyrstals of glycolic acid, the technical solution
In, in order to improve ethyl alcohol acid recovering rate, crystallization temperature is -30 DEG C~50 DEG C.But in fact, the temperature range and unreasonable, spy
When not being that crystallization temperature is down to -20 DEG C or less, water can also crystallize precipitation, and the ethyl alcohol acid crystal for being unable to get high-purity at all produces
Product.In addition, ethyl alcohol acid crystal can be very tiny when crystallization temperature is down to -10 DEG C, it is particularly easy to the moisture absorption, product purity can drop
It is low, hardly result in qualified products.
Chinese patent CN102153461A discloses a kind of method for preparing hydroxyacetic acid by ethylene glycol, the technical solution
Purification purification part is evaporated concentration to feed ethanol aqueous acid before crystallization to improve ethyl alcohol acid recovering rate, but
It is that the program is disadvantageous in that needs are evaporated concentration to whole raw materials, energy consumption is larger, and in the mistake of evaporation and concentration
Cheng Zhong, glycolic, which can polymerize, causes product to lose, and the material of evaporation and concentration is more, then product loss amount will be bigger；And it ties
Brilliant temperature is still higher, and crystallization outlet temperature maintains 8~15 DEG C, and minimum crystallization temperature is up to 8 DEG C, in crystalline mother solution still
There is a large amount of glycolic not to be recovered, actually there are also very big rooms for promotion for the rate of recovery of glycolic.
In conclusion existing glycolic method for crystallising be ensure product purity, generally select at a higher temperature into
Row crystallization, sacrifices product recovery rate, therefore these methods require further improvement, into one on the basis of ensureing product purity
Step improves the rate of recovery, and then improves the efficiency of crystallization process, reduces production energy consumption.
Summary of the invention
That the technical problem to be solved by the present invention is to crystal grains present in the method for the high-purity glycolic of existing production is small,
The easy moisture absorption, the problem that product purity is low, the rate of recovery is low, production energy consumption is high, provide a kind of method for producing high-purity glycolic.
In order to solve the above technical problems, the present invention is as follows using technical solution: glycolic acid aqueous solution carries out in crystallizer I
Crystallisation by cooling obtains the magma I of the acid crystal containing ethyl alcohol；Magma I obtains ethyl alcohol acid crystal I and crystalline mother solution I, second through being separated by solid-liquid separation
Process units is discharged as product after drying in alcohol acid crystal I；Cooling knot is carried out after crystalline mother solution I is concentrated in crystallizer II
Crystalline substance obtains the magma II of the acid crystal containing ethyl alcohol；Magma II obtains ethyl alcohol acid crystal II and crystalline mother solution II, ethyl alcohol through being separated by solid-liquid separation
Process units is discharged as product after drying in acid crystal II；Crystalline mother solution II carries out crystallisation by cooling in crystallizer III, obtains
The magma III of the acid crystal containing ethyl alcohol；Magma III obtains ethyl alcohol acid crystal III and crystalline mother solution III, ethyl alcohol acid crystal through being separated by solid-liquid separation
III returns in crystallizer I or crystallizer II, and process units is discharged in crystalline mother solution III.
In above-mentioned technical proposal, crystalline mother solution I is concentrated, ethyl alcohol acid concentration >=60% preferably in concentrate is more excellent
Select ethyl alcohol acid concentration >=70% in concentrate.
In above-mentioned technical proposal, crystalline mother solution III is condensed into aqueous products, ethyl alcohol acid concentration >=60% in concentrate.
In above-mentioned technical proposal, the operation temperature of crystallizer II is higher than the operation temperature of crystallizer I, the operation of crystallizer I
Temperature is higher than the operation temperature of crystallizer III, and the preferably operation temperature of crystallizer II is 10~20 DEG C, the operation temperature of crystallizer I
It is -20~10 DEG C, the operation temperature of crystallizer III is -20~-10 DEG C.More preferably, the operation temperature of crystallizer II be 12~
16 DEG C, the operation temperature of crystallizer I is -18~8 DEG C, and the operation temperature of crystallizer III is -18~-10 DEG C.
In above-mentioned technical proposal, crystal III is only partly dissolved in crystallizer I or crystallizer II, the dissolution of preferred crystal III
Loss≤20%.More preferably, the solution loss of crystal II is 5-20%.
In above-mentioned technical proposal, the average grain diameter of crystal II is greater than the average grain diameter of crystal I, and the average grain diameter of crystal I is big
In the average grain diameter of crystal III.
In above-mentioned technical proposal, ethyl alcohol acid crystal I and crystal II are washed, it is preferable to use feed ethanol sour water is molten
Liquid, glycolic saturated aqueous solution, 0~10 DEG C of water as cleaning solution, more preferably use 60~70% glycolic saturated solutions as
Cleaning solution.
In above-mentioned technical proposal, crystallizer I and crystallizer II and crystallizer III are produced using continuous crystallisation mode, excellent
It is selected in start-up and crystal seed is added.
In above-mentioned technical proposal, ethyl alcohol acid crystal is added into crystallizer I, crystallizer II and crystallizer III as crystal seed,
Preferred alcohol acid crystals kind amount is respectively the 0.5% of II mass of crystallizer feed ethanol aqueous acid, crystalline mother solution I and crystalline mother solution
~15%, the size distribution of preferred alcohol acid crystals kind is 100 μm~600 μm, preferred alcohol acid crystals kind purity >=99.9%.
In above-mentioned technical proposal, purity >=99.9% of glycolic crystal product, preferred product average grain diameter >=600 μm,
Content≤200ppm of more preferable impurity oxalic acid.
In above-mentioned technical proposal, crystallisation by cooling is directly first carried out to feed ethanol aqueous acid, obtains the production of ethyl alcohol acid crystal
Product, are then concentrated and are crystallized to crystalline mother solution again, on the one hand reduce concentrate quality, and then significantly reduce evaporation
On the other hand energy consumption in concentration process, causes product to lose, due to concentrate although also there is part glycolic that can polymerize
Total amount is reduced, therefore actual product loss also corresponding reduction.
In above-mentioned technical proposal, crystallisation by cooling is carried out to concentrate, impurity is enriched with because of concentration in concentrate, therefore gained
Ethyl alcohol acid crystal is extremely difficult to the requirement of product purity, to continue to obtain qualified products, the solution taken be first compared with
It is crystallized under high-temperature, due to crystallization temperature height, crystal is easily grown up, therefore product purity is able to satisfy requirement, then again to residue
Crystalline mother solution be further continued for crystallizing, to improve the rate of recovery, but since crystallization temperature at this time is lower, crystal is very tiny, product purity
It is low, it cannot be returned directly to again in the crystallizer of high temperature directly as product, therefore by this partial crystals, pass through the part of crystal
Dissolution obtains qualified products again, and benefit is: 1) reducing separating energy consumption.When low temperature crystallization, crystal can be very tiny, product purity
It is usually lower, it cannot function as product extraction.Traditional solution is will to recrystallize again after the dissolution of this partial crystals, but energy consumption
It is larger.And in the present solution, three-level crystallographic back in level-one or secondary crystallizer, crystal and without being all dissolved
Fall, at most only part is dissolved, and most crystal are still used as product to produce, therefore, and compared with traditional recrystallization method, energy
Save a large amount of energy consumptions.2) product purity is improved.Three-level crystallographic is partly dissolved in level-one or secondary crystallizer, mainly
Fine grain dissolves, and fine grain, which dissolves generated degree of supersaturation, can promote remaining crystal to grow up, therefore overall recovery is constant, and also
The average grain diameter of crystal can be improved, separation of solid and liquid and dry efficiency is promoted, can finally improve product purity, and reduces product suction
Tide.
It using the method for production high purity ethanol acid of the invention, by three-level crystallization and is once concentrated, and by three-level
Crystallographic returns in level-one or secondary crystallizer, has ensured product purity, and improve the rate of recovery of glycolic, Jin Erbao
Hinder product yield, while having reduced production energy consumption, achieves preferable technical effect.
Detailed description of the invention
Fig. 1 is the flow diagram of the production method of high purity ethanol acid of the present invention.
Glycolic acid aqueous solution carries out crystallisation by cooling in crystallizer I, obtains the magma I of the acid crystal containing ethyl alcohol；Magma I is through solid
Process units is discharged as product after drying in the isolated ethyl alcohol acid crystal I of liquid and crystalline mother solution I, ethyl alcohol acid crystal I；Crystallization
Crystallisation by cooling is carried out after mother liquor I is concentrated in crystallizer II, obtains the magma II of the acid crystal containing ethyl alcohol；Magma II is through solid-liquid point
From ethyl alcohol acid crystal II and crystalline mother solution II is obtained, process units is discharged as product after drying in ethyl alcohol acid crystal II；Crystallization
Mother liquor II carries out crystallisation by cooling in crystallizer III, obtains the magma III of the acid crystal containing ethyl alcohol；Magma III is obtained through being separated by solid-liquid separation
Ethyl alcohol acid crystal III and crystalline mother solution III, ethyl alcohol acid crystal III return in crystallizer I or crystallizer II, and crystalline mother solution III is discharged
Process units.
Specific embodiment
Below by embodiment, the present invention is further elaborated.
[embodiment 1]
The production method of high purity ethanol acid of the present invention.
As described in Figure 1, glycolic acid aqueous solution carries out crystallisation by cooling in crystallizer I, contains ethyl alcohol in feed ethanol acid solution 1
Sour (free acid) 64%, total acid 70%, crystallization temperature are -15 DEG C, obtain the magma I of the acid crystal containing ethyl alcohol；Magma I is through solid-liquid
Process units is discharged as product after drying in isolated ethyl alcohol acid crystal I and crystalline mother solution I, ethyl alcohol acid crystal I, product
Purity is 99.9%, 600 μm of average grain diameter；Crystallisation by cooling is carried out after crystalline mother solution I is concentrated in crystallizer II, in concentrate
Containing free acid 70%, crystallization temperature is 10 DEG C, obtains the magma II of the acid crystal containing ethyl alcohol；Magma II obtains ethyl alcohol through being separated by solid-liquid separation
Process units is discharged as product after drying in acid crystal II and crystalline mother solution II, ethyl alcohol acid crystal II, and the purity of product is
99.95%, 650 μm of average grain diameter；Crystalline mother solution II carries out crystallisation by cooling in crystallizer III, and crystallization temperature is -15 DEG C, obtains
The magma III of the acid crystal containing ethyl alcohol；Magma III obtains ethyl alcohol acid crystal III and crystalline mother solution III, ethyl alcohol acid crystal through being separated by solid-liquid separation
III average grain diameter is 400 μm, back in crystallizer I, loses 20% because fine grain dissolves in crystallizer I, crystalline mother solution
III discharge process units, glycolic overall recovery are 76%.
[embodiment 2]
The production method of high purity ethanol acid of the present invention.
As described in Figure 1, glycolic acid aqueous solution carries out crystallisation by cooling in crystallizer I, contains ethyl alcohol in feed ethanol acid solution 1
Sour (free acid) 64%, total acid 70%, crystallization temperature are -18 DEG C, obtain the magma I of the acid crystal containing ethyl alcohol；Magma I is through solid-liquid
Process units is discharged as product after drying in isolated ethyl alcohol acid crystal I and crystalline mother solution I, ethyl alcohol acid crystal I, product
Purity is 99.9%, 500 μm of average grain diameter；Crystallisation by cooling is carried out after crystalline mother solution I is concentrated in crystallizer II, in concentrate
Containing free acid 70%, crystallization temperature is 12 DEG C, obtains the magma II of the acid crystal containing ethyl alcohol；Magma II obtains ethyl alcohol through being separated by solid-liquid separation
Process units is discharged as product after drying in acid crystal II and crystalline mother solution II, ethyl alcohol acid crystal II, and the purity of product is
99.95%, 650 μm of average grain diameter；Crystalline mother solution II carries out crystallisation by cooling in crystallizer III, and crystallization temperature is -18 DEG C, obtains
The magma III of the acid crystal containing ethyl alcohol；Magma III obtains ethyl alcohol acid crystal III and crystalline mother solution III, ethyl alcohol acid crystal through being separated by solid-liquid separation
III average grain diameter is 300 μm, back in crystallizer II, loses 15% because fine grain dissolves in crystallizer II, crystallization is female
Process units is discharged in liquid III, and glycolic overall recovery is 80%.
[embodiment 3]
The production method of high purity ethanol acid of the present invention.
As described in Figure 1, according to the operating condition of embodiment 1, first degree crystalline device temperature is 8 DEG C, and secondary crystallizer temperature is
16 DEG C, three-level mould temperature is -10 DEG C, and three-level crystallographic average grain diameter is 500 μm, back in crystallizer I, is being crystallized
10% is lost because fine grain dissolves in device I, first degree crystalline product purity is 99.95%, and average grain diameter is 800 μm, secondary crystallization
Product purity is 99.99%, and average grain diameter is 900 μm, and glycolic overall recovery is 55%.
[embodiment 4]
The production method of high purity ethanol acid of the present invention.
As described in Figure 1, according to the operating condition of embodiment 2, first degree crystalline device temperature is 5 DEG C, and secondary crystallizer temperature is
15 DEG C, three-level mould temperature is -12 DEG C, and 450 μm of three-level crystallographic average grain diameter is being crystallized back in crystallizer II
5% is lost because fine grain dissolves in device II, first degree crystalline product purity 99.93%, 780 μm of average grain diameter, secondary crystallization product
Purity 99.99%, 850 μm of average grain diameter, glycolic overall recovery is 60%.
[comparative example 1]
Chinese patent " a method of high purity ethanol acid crystal is prepared by methyl glycollate " (CN103508878A) institute
State the production method of high-purity glycolic.
According to the operating condition of embodiment 1, crystallization temperature is -10 DEG C, and the purity of product is 99.2%, 200 μ of average grain diameter
M, ethyl alcohol acid recovering rate are 37%.
[comparative example 2]
Chinese patent " a method of hydroxyacetic acid is prepared by ethylene glycol " (CN102153461B) described high-purity glycolic
Production method.
According to the operating condition of embodiment 3, concentrate crystallization temperature is 8 DEG C, and the purity of product is 99.2%, average grain diameter
300 μm, ethyl alcohol acid recovering rate is 27%.
[embodiment 5]
The production method of high purity ethanol acid of the present invention.
As described in Figure 1, it according to the operating condition of embodiment 1, is produced using continuous crystallisation mode, start-up is to knot
Ethyl alcohol acid crystal is added in brilliant device I, crystallizer II and crystallizer III as crystal seed, glycolic crystal seed amount is respectively crystallizer charging
The 5% of II mass of glycolic acid aqueous solution, crystalline mother solution I and crystalline mother solution, the size distribution of glycolic crystal seed are 300 μm, ethyl alcohol
Acid crystals kind purity is 99.9%, and the average grain diameter of ethyl alcohol acid crystal III is 500 μm, is returned in crystallizer I, in crystallizer I
20% is lost because of fine grain dissolution, the purity of product is 99.99%, and average grain diameter is 800 μm, and secondary crystallization product purity is
99.99%, average grain diameter is 900 μm, and glycolic overall recovery is 76%.
[embodiment 6]
The production method of high purity ethanol acid of the present invention.
As described in Figure 1, it according to the operating condition of embodiment 2, is produced using continuous crystallisation mode, start-up is to knot
Ethyl alcohol acid crystal is added in brilliant device I, crystallizer II and crystallizer III as crystal seed, glycolic crystal seed amount is respectively crystallizer charging
The 10% of II mass of glycolic acid aqueous solution, crystalline mother solution I and crystalline mother solution, the size distribution of glycolic crystal seed are 350 μm, ethyl alcohol
Acid crystals kind purity is 99.9%, and the average grain diameter of ethyl alcohol acid crystal III is 550 μm, is returned in crystallizer II, in crystallizer II
Middle to lose 15% because of fine grain dissolution, the purity of product is 99.99%, and average grain diameter is 850 μm, and secondary crystallization product purity is
99.99%, average grain diameter is 950 μm, and glycolic overall recovery is 80%.
Claims (10)
1. a kind of method for producing high purity ethanol acid, comprising the following steps:
A) glycolic acid aqueous solution carries out crystallisation by cooling in crystallizer I, obtains the magma I of the acid crystal containing ethyl alcohol；
B) magma I obtains ethyl alcohol acid crystal I and crystalline mother solution I through being separated by solid-liquid separation, and ethyl alcohol acid crystal I is arranged as product after drying
Process units out；
C) crystallisation by cooling is carried out after crystalline mother solution I is concentrated in crystallizer II, obtains the magma II of the acid crystal containing ethyl alcohol；
D) magma II obtains ethyl alcohol acid crystal II and crystalline mother solution II through being separated by solid-liquid separation, and ethyl alcohol acid crystal II is after drying as production
Process units is discharged in product；
E) crystalline mother solution II carries out crystallisation by cooling in crystallizer III, obtains the magma III of the acid crystal containing ethyl alcohol；
F) magma III obtains ethyl alcohol acid crystal III and crystalline mother solution III through being separated by solid-liquid separation, and ethyl alcohol acid crystal III returns to crystallizer I
Or in crystallizer II, process units is discharged in crystalline mother solution III.
2. the method for production high purity ethanol acid according to claim 1, it is characterised in that carried out to crystalline mother solution I dense
Contracting.
3. the method for production high purity ethanol acid according to claim 1, it is characterised in that crystalline mother solution III to be condensed into
Aqueous products, ethyl alcohol acid concentration >=60% in concentrate.
4. the method for production high purity ethanol acid according to claim 1, it is characterised in that the operation temperature of crystallizer II
Higher than the operation temperature of crystallizer I, the operation temperature of crystallizer I is higher than the operation temperature of crystallizer III.
5. the method for production high purity ethanol acid according to claim 1, it is characterised in that crystal III is in crystallizer I or knot
It is only partly dissolved in brilliant device II.
6. the method for production high purity ethanol acid according to claim 1, it is characterised in that the average grain diameter of crystal II is big
In the average grain diameter of crystal I, the average grain diameter of crystal I is greater than the average grain diameter of crystal III.
7. the method for production high purity ethanol acid according to claim 1, it is characterised in that ethyl alcohol acid crystal I and crystal
II is washed.
8. it is according to claim 1 production high purity ethanol acid method, it is characterised in that crystallizer I and crystallizer II and
Crystallizer III is produced using continuous crystallisation mode.
9. the method for production high purity ethanol acid according to claim 1, it is characterised in that crystallizer I, crystallizer II
With addition ethyl alcohol acid crystal in crystallizer III as crystal seed.
10. it is according to claim 1 production high purity ethanol acid method, it is characterised in that glycolic crystal product it is pure
Degree >=99.9%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710982580.2A CN109694318A (en) | 2017-10-20 | 2017-10-20 | The method for producing high purity ethanol acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710982580.2A CN109694318A (en) | 2017-10-20 | 2017-10-20 | The method for producing high purity ethanol acid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109694318A true CN109694318A (en) | 2019-04-30 |
Family
ID=66225245
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710982580.2A Pending CN109694318A (en) | 2017-10-20 | 2017-10-20 | The method for producing high purity ethanol acid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109694318A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112645814A (en) * | 2019-10-10 | 2021-04-13 | 中国石油化工股份有限公司 | Method for purifying glycolic acid, glycolic acid crystal and use thereof |
| CN112691402A (en) * | 2020-12-23 | 2021-04-23 | 安徽英特力工业工程技术有限公司 | Vertical melt crystallizer |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2260738A (en) * | 1938-09-08 | 1941-10-28 | Dow Chemical Co | Manufacture of crystalline glycollic acid |
| WO1992005138A1 (en) * | 1990-09-20 | 1992-04-02 | E.I. Du Pont De Nemours And Company | Manufacture of high-purity hydroxyacetic acid |
| CN101080378A (en) * | 2004-12-17 | 2007-11-28 | 株式会社吴羽 | Process for purifying hydroxycarboxylic acid, process for producing cyclic ester, and process for producing polylhydroxycaboxylic acid |
| US20080091047A1 (en) * | 2006-10-12 | 2008-04-17 | Gallagher F Glenn | Multi-stage glycolic acid crystallization |
| WO2012160256A1 (en) * | 2011-05-23 | 2012-11-29 | Upm-Kymmene Corporation | Method and apparatus for separating a hydroxycarboxylic acid product |
| CN102964240A (en) * | 2012-12-10 | 2013-03-13 | 西南化工研究设计院有限公司 | Preparation method of high-purity glycolic acid crystals |
| 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 |
-
2017
- 2017-10-20 CN CN201710982580.2A patent/CN109694318A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2260738A (en) * | 1938-09-08 | 1941-10-28 | Dow Chemical Co | Manufacture of crystalline glycollic acid |
| WO1992005138A1 (en) * | 1990-09-20 | 1992-04-02 | E.I. Du Pont De Nemours And Company | Manufacture of high-purity hydroxyacetic acid |
| CN101080378A (en) * | 2004-12-17 | 2007-11-28 | 株式会社吴羽 | Process for purifying hydroxycarboxylic acid, process for producing cyclic ester, and process for producing polylhydroxycaboxylic acid |
| US20080091047A1 (en) * | 2006-10-12 | 2008-04-17 | Gallagher F Glenn | Multi-stage glycolic acid crystallization |
| WO2012160256A1 (en) * | 2011-05-23 | 2012-11-29 | Upm-Kymmene Corporation | Method and apparatus for separating a hydroxycarboxylic acid product |
| CN102964240A (en) * | 2012-12-10 | 2013-03-13 | 西南化工研究设计院有限公司 | Preparation method of high-purity glycolic acid crystals |
| 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 |
Non-Patent Citations (3)
| Title |
|---|
| 党建章: "《发酵工艺教程（第二版）》", 31 July 2016, 中国轻工业出版社 * |
| 康彦芳: "《化工分离技术》", 31 January 2014, 中央广播电视大学出版社 * |
| 张辉辉: "乙醇酸甲酯水解制备乙醇酸的研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112645814A (en) * | 2019-10-10 | 2021-04-13 | 中国石油化工股份有限公司 | Method for purifying glycolic acid, glycolic acid crystal and use thereof |
| CN112691402A (en) * | 2020-12-23 | 2021-04-23 | 安徽英特力工业工程技术有限公司 | Vertical melt crystallizer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109608372B (en) | Multistage continuous crystallization method of short rod-shaped methionine crystal | |
| CN1284755C (en) | Xylitol refining crystallization process | |
| CN109694318A (en) | The method for producing high purity ethanol acid | |
| CN105031963B (en) | A kind of integrated anti-solvent-vacuum evaporation-cooling or the method for crystallising of anti-solvent | |
| CN110527854A (en) | Method for preparing particle size controllable ultra-pure ammonium rhenate crystal | |
| CN103396406B (en) | Preparation method of candesartan cilexetil | |
| CN109694317A (en) | The production method of high purity ethanol acid | |
| CN100567312C (en) | Continuous crystallisation process in the glyphosate production | |
| CN104355990B (en) | Method for recycling and mechanically using L- (+) -tartaric acid in D-ethyl ester production | |
| CN109928982A (en) | A kind of qinghaosu separation purifying technique | |
| CN103450287B (en) | A kind of glucose mother liquid recycling technique | |
| CN102371081A (en) | Crystallization method with a fine crystal elimination | |
| CN102371082B (en) | Crystallization method with overflow of clear mother liquor | |
| CN112479944B (en) | Taurine and recrystallization method thereof | |
| EP2374786A1 (en) | Purification of monochloroacetic acid rich streams | |
| CN104592053A (en) | Industrial preparation method of high-purity sodium pantothenate | |
| CN114477235A (en) | Crystallization method of sodium chloride | |
| CN107840790B (en) | Production method of glycolic acid crystals | |
| CN114380317B (en) | Method for recycling hydrochloric acid by recovering calcium sulfate from pickle liquor | |
| JPH0361605B2 (en) | ||
| US2102380A (en) | Process of crystallizing pure d-glucono-delta-lactone | |
| CN207158800U (en) | A kind of device for efficiently reducing magnesium sulfate water content | |
| CN108975354B (en) | Method for coproducing medicinal mirabilite and anhydrous sodium sulphate | |
| CN103755577A (en) | Method for recovering ambroxol base from ambroxol hydrochloride refined mother solution | |
| CN108905263A (en) | A kind of production method of paracetamol fine grain |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20190430 |
|
| RJ01 | Rejection of invention patent application after publication |