CN104610061A - Preparation method of electronic ethyl lactate - Google Patents
Preparation method of electronic ethyl lactate Download PDFInfo
- Publication number
- CN104610061A CN104610061A CN201510063085.2A CN201510063085A CN104610061A CN 104610061 A CN104610061 A CN 104610061A CN 201510063085 A CN201510063085 A CN 201510063085A CN 104610061 A CN104610061 A CN 104610061A
- Authority
- CN
- China
- Prior art keywords
- ethyl lactate
- ions
- electronic
- preparation
- grade
- 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.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/56—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C67/54—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a preparation method of electronic ethyl lactate. According to the method, food-grade ethyl lactate is used as a raw material and absorbed by ion exchange resin to remove most of metal ions; then the pressure reduction rectification is carried out so as to remove water, light-component impurities and heavy-component impurities; finally, sub-boiling distillation is carried out in the presence of high-purity nitrogen to remove metal ions, so as to obtain electronic ethyl lactate. The prepared electronic ethyl lactate contains not less than 99.99% of ethyl lactate, not greater than 1ppb of lead ions, copper ions, iron ions, magnesium ions, arsenic ions, calcium ions, aluminum ions, zinc ions, manganese ions, mercury ions, chromium ions, nickel ions, potassium ions and sodium ions, and not greater than 100ppm of water; the acidity of the prepared electronic ethyl lactate is not greater than 65ppm; therefore, the electronic grade is met. The whole preparation does not involve the emission of wastewater, waste gas and waste slag, has a low requirement on a device, does not need large reflux ratio during rectifying, can be used for greatly reducing the energy consumption to save the cost, and is fast, efficient, environmentally friendly and free of pollution.
Description
Technical field
The present invention relates to the purification process of ethyl lactate, refer to a kind of preparation method of electronic-grade ethyl lactate particularly.
Background technology
Electronic-grade ethyl lactate is mainly used in the cleaning of precise electronic components and parts, has aromatising flavour, low volatility, effectively improves the strong and stimulating smell of conventional solvent; Be high boiling solvent (145 ~ 190 DEG C), to grease, Polymeric Soil, water-soluble stains, there is extremely strong dissolving power and the solvability of uniqueness; As clean-out system, have loss compared with other clean-out system little, cost performance is high, has no adverse effects to cleaned material.
The purification technique of electronic-grade ethyl lactate, it is the systems approach of electronic-grade ethyl lactate by food grade lactic acid ethyl ester rectification and purification that Chinese patent CN102320969A discloses a kind of.In the method, rectifying needs very large reflux ratio, and equipment requirements is higher, and production efficiency is lower, and energy consumption is comparatively large, and product is subject to contaminating impurity in air, and purity is unsecured.
Summary of the invention
Object of the present invention is exactly to overcome the deficiency existing for prior art, provides a kind of preparation method of electronic-grade ethyl lactate energy-efficient, free from environmental pollution.
For achieving the above object, the preparation method of the electronic-grade ethyl lactate designed by the present invention, comprises the following steps:
1) ion exchange resin absorption: food grade lactic acid ethyl ester is first used macroreticular weakly base styrene series anion resin absorption, again with macropore acidulous acrylic acid's cation resin ion resin and the absorption of neutral ion exchange resin, removing most of metal ion wherein;
2) rectification under vacuum: by step 1) ethyl lactate after process adds in rectifying tower and carries out rectification under vacuum, temperature at the bottom of rectifying tower reactor 61 ~ 145 DEG C, tower top temperature is 32 ~ 90 DEG C, and condensate temperature is 2 ~ 10 DEG C, reflux ratio is 10:1 ~ 15:1, removing moisture and light, heavy constituent impurity;
3) sub-boiling distillation: by through step 2) ethyl lactate that processes joins in sub-boiling distillation device; under high pure nitrogen protection, ethyl lactate is heated to below boiling point 5 ~ 10 DEG C; remove metal ion, obtain content and be greater than 99.99% and metal ion content is all less than the electronic-grade ethyl lactate of 1ppb.
Preferably, step 1 of the present invention) in ion exchange resin absorption, often kind of ion-exchange column length of use is not less than 3m; Flow velocity 4 ~ 10m/h.
Preferably, step 2 of the present invention) in rectification under vacuum, temperature at the bottom of rectifying tower reactor is 69 ~ 71 DEG C, and tower top temperature is 38 ~ 42 DEG C, and condensate temperature is 2 ~ 5 DEG C, and reflux ratio is 12:1, the strong 700 ~ 900pa of still base pressure, refluxes 3 ~ 5 hours.
Step 2 of the present invention) in rectification under vacuum, the tower height of rectifying tower used is 1.3m, and tower internal diameter is 34mm, and the filler in rectifying tower used is triangle helical packing, net ring filler or glass spring filler.Filler used is preferably 316L type 1.5mm × 1.5mm triangle helical packing, and theoretical plate number is 41 ~ 45.
Step 3 of the present invention) in sub-boiling distillation, described sub-boiling distillation device needs first re-use through pre-treatment, and pretreatment process for first to soak 24 hours with chloroazotic acid, then rinses repeatedly with ultrapure water, reaches 18.25M Ω cm@25 DEG C to washing out resistivity of water.
Ethyl lactate is heated to below boiling point 5 ~ 10 DEG C and carries out sub-boiling distillation by the present invention under high pure nitrogen protection; because ethyl lactate does not reach boiling point; also be just no longer made up of a large amount of steam thing grain with the gas phase of liquid equilibrium; but with molecularity and liquid equilibrium; therefore, seldom carry secretly in steam or do not carry metal ion and solia particle secretly.This steam being present in gas-phase space with molecularity, is condensed into liquid again on condensation tube wall, and the content of the ethyl lactate obtained thus is greater than 99.99%, and impurity metal ion content can not higher than 1ppb.
The present invention with food grade lactic acid ethyl ester for raw material, through ion exchange resin absorption, rectifying, sub-boiling distillation, content of ethyl lactate >=99.99% obtained, the each ion content of lead, copper, iron, magnesium, arsenic, calcium, aluminium, zinc, manganese, mercury, chromium, nickel, potassium, sodium all≤1ppb, moisture content≤100ppm, acidity≤65ppm, meets electronics rank.Compared with prior art, the present invention has following characteristics:
1, ion exchange resin of the present invention absorption and rectifying carry out in general room, carry out without the need in dust free chamber again, can investment reduction cost significantly.
2, rectifying is without the need to very large reflux ratio, only need carry out at 10:1 ~ 15:1, improve production efficiency, can reduce energy consumption significantly with cost-saving.
3, sub-boiling distillation carries out under high pure nitrogen protection, not only avoids contaminating impurity in air, also improves distillation efficiency while increasing high pure nitrogen air-flow.
4, the present invention adopts anion-cation exchange resin, can reuse, and ion exchange resin is after for some time uses, and ionic adsorption effect can obviously decline, and can circulate repeatedly use through manipulation of regeneration; Corrosion can not be caused to equipment, reduce equipment Meteorological again.
5, the present invention's rectifying tower used, a small amount of heavy constituent at the bottom of tower, can continue to use as food grade lactic acid ethyl ester through decolouring, tower top light constituent because of water content exceeds standard can through rectifying and dewatering again, whole process does not have the waste of raw material substantially.
6, the whole preparation process of the present invention does not relate to the discharge of waste water,waste gas and industrial residue, lower to equipment requirements, and relatively rapidly and efficiently, whole process environmental protection is pollution-free.
Embodiment
In order to explain the present invention better, below in conjunction with specific embodiment, the present invention is described in further detail, but they do not form restriction to the present invention.Some nonessential amendment and adjustment that other people make according to the present invention, still belong to protection scope of the present invention.Other unspecified part is prior art.
In the present invention, said chloroazotic acid is that the ratio being 1: 3 by volume in concentrated nitric acid and concentrated hydrochloric acid mixes.
Embodiment 1
1) ion exchange resin absorption: by 2000ml content 99% food grade lactic acid ethyl ester, successively by being equipped with the ion exchange column of macroreticular weakly base styrene series anion resin absorption, macropore acidulous acrylic acid cation resin ion resin, the length of often kind of ion exchange column is 3m, flow velocity 6m/h, after ion exchange column, in ethyl lactate, most of metal ion can control within 100ppb, but moisture slightly rises.
2) rectification under vacuum: the ethyl lactate adsorbed through ion-exchange is added in laboratory self-control rectifying tower and carry out rectification under vacuum, the tower height of rectifying tower is 1.3m, tower internal diameter is 34mm, and filler used is preferably 316L type 1.5mm × 1.5mm triangle helical packing, and theoretical plate number is 41 ~ 45; Temperature at the bottom of rectifying tower reactor is 69 ~ 71 DEG C, and tower top temperature is 38 ~ 42 DEG C, and condensate temperature is 2 ~ 5 DEG C, the strong 700 ~ 900pa of still base pressure, refluxes 3 hours; The first a small amount of water of extraction and ethyl lactate blend are about 50ml, then adopt the way of the full extraction of repeatedly total reflux, when extraction sample reaches 99.99%, stablize the continuous extraction of reflux ratio 12:1,
3) sub-boiling distillation: sub-boiling distillation device first re-uses through pre-treatment, pretreatment process for first to soak 24 hours with chloroazotic acid, then rinses repeatedly with ultrapure water, reaches 18.25M Ω cm@25 DEG C to washing out resistivity of water; By through step 2) ethyl lactate after process joins in pretreated sub-boiling distillation device; first replace sub-boiling distillation device 4 ~ 6 times with high pure nitrogen; drain air; under high pure nitrogen protection, ethyl lactate is heated to below boiling point 5 ~ 10 DEG C; remove metal ion, obtain 1750ml electronic-grade ethyl lactate altogether.Wherein, the content of ethyl lactate is 99.99%, each ion content of lead, copper, iron, magnesium, arsenic, calcium, aluminium, zinc, manganese, mercury, chromium, nickel, potassium, sodium all≤1ppb, moisture content≤100ppm, acidity≤65ppm.
Embodiment 2
1) ion exchange resin absorption: by 2000ml content 99% food grade lactic acid ethyl ester, successively by being equipped with the ion exchange column of macroreticular weakly base styrene series anion resin absorption, macropore acidulous acrylic acid cation resin ion resin and neutral ion exchange resin, the length of often kind of ion exchange column is 3m, flow velocity 4m/h, after ion exchange column, in ethyl lactate, most of metal ion can control within 100ppb, but moisture slightly rises.
2) rectification under vacuum: the ethyl lactate adsorbed through ion-exchange is added in laboratory self-control rectifying tower and carry out rectification under vacuum, the tower height of rectifying tower is 1.3m, tower internal diameter is 34mm, and filler used is preferably 316L type 1.5mm × 1.5mm triangle helical packing, and theoretical plate number is 41 ~ 45; Temperature at the bottom of rectifying tower reactor is 80 ~ 84 DEG C, and tower top temperature is 43 ~ 46 DEG C, and condensate temperature is 2 ~ 5 DEG C, the strong 700 ~ 900pa of still base pressure, refluxes 3 hours; The first a small amount of water of extraction and ethyl lactate blend are about 70ml, then adopt the way of the full extraction of repeatedly total reflux, when extraction sample reaches 99.99%, stablize the continuous extraction of reflux ratio 10:1,
3) sub-boiling distillation: sub-boiling distillation device first re-uses through pre-treatment, pretreatment process for first to soak 24 hours with chloroazotic acid, then rinses repeatedly with ultrapure water, reaches 18.25M Ω cm@25 DEG C to washing out resistivity of water; By through step 2) ethyl lactate after process joins in pretreated sub-boiling distillation device; first replace sub-boiling distillation device 4 ~ 6 times with high pure nitrogen; drain air; under high pure nitrogen protection, ethyl lactate is heated to below boiling point 5 ~ 10 DEG C; remove metal ion, obtain 1630ml electronic-grade ethyl lactate altogether.Wherein, the content of ethyl lactate is 99.99%, each ion content of lead, copper, iron, magnesium, arsenic, calcium, aluminium, zinc, manganese, mercury, chromium, nickel, potassium, sodium all≤1ppb, moisture content≤100ppm, acidity≤65ppm.
Embodiment 3
1) ion exchange resin absorption: by 2000ml content 99% food grade lactic acid ethyl ester, successively by being equipped with the ion exchange column of macroreticular weakly base styrene series anion resin absorption, macropore acidulous acrylic acid cation resin ion resin and neutral ion exchange resin, the length of often kind of ion exchange column is 3m, flow velocity 10m/h, after ion exchange column, in ethyl lactate, most of metal ion can control within 100ppb.
2) rectification under vacuum: the ethyl lactate adsorbed through ion-exchange is added in laboratory self-control rectifying tower and carry out rectification under vacuum, the tower height of rectifying tower is 1.3m, tower internal diameter is 34mm, and filler used is preferably 316L type 1.5mm × 1.5mm triangle helical packing, and theoretical plate number is 41 ~ 45; Temperature at the bottom of rectifying tower reactor is 62 ~ 65 DEG C, and tower top temperature is 34 ~ 37 DEG C, and condensate temperature is 2 ~ 5 DEG C, the strong 700 ~ 900pa of still base pressure, refluxes 5 hours; The first a small amount of water of extraction and ethyl lactate blend are about 40ml, then adopt the way of the full extraction of repeatedly total reflux, when extraction sample reaches 99.99%, stablize the continuous extraction of reflux ratio 15:1, removing moisture and light, the impurity that grades of recombinating;
3) sub-boiling distillation: sub-boiling distillation device first re-uses through pre-treatment, pretreatment process for first to soak 24 hours with chloroazotic acid, then rinses repeatedly with ultrapure water, reaches 18.25M Ω cm@25 DEG C to washing out resistivity of water; By through step 2) ethyl lactate after process joins in pretreated sub-boiling distillation device; first replace sub-boiling distillation device 4 ~ 6 times with high pure nitrogen; drain air; under high pure nitrogen protection, ethyl lactate is heated to below boiling point 5 ~ 10 DEG C; remove metal ion, obtain 1810ml electronic-grade ethyl lactate altogether.Wherein, the content of ethyl lactate is 99.99%, each ion content of lead, copper, iron, magnesium, arsenic, calcium, aluminium, zinc, manganese, mercury, chromium, nickel, potassium, sodium all≤1ppb, moisture content≤100ppm, acidity≤65ppm.
Claims (5)
1. a preparation method for electronic-grade ethyl lactate, is characterized in that: it comprises the following steps:
1) ion exchange resin absorption: food grade lactic acid ethyl ester is first used macroreticular weakly base styrene series anion resin absorption, again with macropore acidulous acrylic acid's cation resin ion resin and the absorption of neutral ion exchange resin, removing most of metal ion wherein;
2) rectification under vacuum: by step 1) ethyl lactate after process adds in rectifying tower and carries out rectification under vacuum, temperature at the bottom of rectifying tower reactor 61 ~ 145 DEG C, tower top temperature is 32 ~ 90 DEG C, and condensate temperature is 2 ~ 10 DEG C, reflux ratio is 10:1 ~ 15:1, removing moisture and light, heavy constituent impurity;
3) sub-boiling distillation: by through step 2) ethyl lactate after process joins in sub-boiling distillation device; under high pure nitrogen protection, ethyl lactate is heated to below boiling point 5 ~ 10 DEG C; remove metal ion, obtain content and be greater than 99.99% and metal ion content is all less than the electronic-grade ethyl lactate of 1ppb.
2. the preparation method of electronic-grade ethyl lactate according to claim 1, is characterized in that: step 1) ion exchange resin absorption in, the length of often kind of ion exchange column used is not less than 3m, flow velocity 4 ~ 10m/h.
3. the preparation method of electronic-grade ethyl lactate according to claim 1, it is characterized in that: step 2) in rectification under vacuum, temperature at the bottom of rectifying tower reactor is 69 ~ 71 DEG C, tower top temperature is 38 ~ 42 DEG C, condensate temperature is 2 ~ 5 DEG C, reflux ratio is 12:1, the strong 700 ~ 900pa of still base pressure, refluxes 3 ~ 5 hours.
4. the preparation method of electronic-grade ethyl lactate according to claim 1, it is characterized in that: step 2) in rectification under vacuum, the tower height of described rectifying tower is 1.3m, and tower internal diameter is 34mm, and the filler in rectifying tower used is triangle helical packing, net ring filler or glass spring filler.
5. the preparation method of electronic-grade ethyl lactate according to claim 1, it is characterized in that: step 3) in sub-boiling distillation, described sub-boiling distillation device needs first to re-use through pre-treatment, pretreatment process is for first to soak 24 hours with chloroazotic acid, repeatedly rinsing with ultrapure water again, reaching 18.25M Ω cm@25 DEG C to washing out resistivity of water.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510063085.2A CN104610061B (en) | 2015-02-06 | 2015-02-06 | The preparation method of electron level ethyl lactate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510063085.2A CN104610061B (en) | 2015-02-06 | 2015-02-06 | The preparation method of electron level ethyl lactate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104610061A true CN104610061A (en) | 2015-05-13 |
| CN104610061B CN104610061B (en) | 2016-09-28 |
Family
ID=53144752
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510063085.2A Active CN104610061B (en) | 2015-02-06 | 2015-02-06 | The preparation method of electron level ethyl lactate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104610061B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2017057320A1 (en) * | 2015-10-02 | 2017-04-06 | 三菱瓦斯化学株式会社 | High-purity carboxylic acid ester and method for producing same |
| CN109160876A (en) * | 2018-11-06 | 2019-01-08 | 湖南东为化工新材料有限公司 | A kind of preparation method of electronic grade cyclohexanone |
| CN109455683A (en) * | 2018-11-23 | 2019-03-12 | 宜宾海丰和锐有限公司 | A method of purifying hydrazine hydrate prepares electron level hydrazine hydrate |
| CN109970555A (en) * | 2018-12-28 | 2019-07-05 | 深圳光华伟业股份有限公司 | The preparation method of electron level n propyl propionate |
| CN112898154A (en) * | 2021-01-21 | 2021-06-04 | 宁波南大光电材料有限公司 | Method for removing water in ethyl lactate |
| CN112920161A (en) * | 2021-01-27 | 2021-06-08 | 宁波南大光电材料有限公司 | Electronic-grade dioxane and preparation method thereof |
| CN113004119A (en) * | 2019-12-19 | 2021-06-22 | 安集微电子（上海）有限公司 | Preparation method of electronic-grade reagent |
| CN115353121A (en) * | 2022-09-01 | 2022-11-18 | 阜新泽程化工有限责任公司 | Industrial production method of electronic pure ammonium sulfite |
| WO2022241690A1 (en) * | 2021-05-19 | 2022-11-24 | Dow Global Technologies Llc | Processes for purifying organic amines |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58189138A (en) * | 1982-04-21 | 1983-11-04 | エス・カ−・ヴエ−・トロ−ストベルク・アクチエンゲゼルシヤフト | Continuous purification of methyl lactate ester |
| US20050096481A1 (en) * | 2001-10-05 | 2005-05-05 | Rainer Hildebrandt | Method for producing a hydroxyacid esters |
| CN102320969A (en) * | 2011-06-10 | 2012-01-18 | 天津大学 | System and method for rectifying and purifying food grade ethyl lactate into electronic grade ethyl lactate |
| CN102381973A (en) * | 2011-09-19 | 2012-03-21 | 南京大学 | Production process of ultra-high purity (electronic grade) lactate product |
| CN103801097A (en) * | 2012-11-15 | 2014-05-21 | 宜昌瑞特精细化工有限公司 | Ultraclean high-purity reagent sub-boiling distillation device |
-
2015
- 2015-02-06 CN CN201510063085.2A patent/CN104610061B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58189138A (en) * | 1982-04-21 | 1983-11-04 | エス・カ−・ヴエ−・トロ−ストベルク・アクチエンゲゼルシヤフト | Continuous purification of methyl lactate ester |
| US20050096481A1 (en) * | 2001-10-05 | 2005-05-05 | Rainer Hildebrandt | Method for producing a hydroxyacid esters |
| CN102320969A (en) * | 2011-06-10 | 2012-01-18 | 天津大学 | System and method for rectifying and purifying food grade ethyl lactate into electronic grade ethyl lactate |
| CN102381973A (en) * | 2011-09-19 | 2012-03-21 | 南京大学 | Production process of ultra-high purity (electronic grade) lactate product |
| CN103801097A (en) * | 2012-11-15 | 2014-05-21 | 宜昌瑞特精细化工有限公司 | Ultraclean high-purity reagent sub-boiling distillation device |
Non-Patent Citations (1)
| Title |
|---|
| 高静等: "催化精馏制备乳酸乙酯", 《化工学报》 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11046634B2 (en) * | 2015-10-02 | 2021-06-29 | Mitsubishi Gas Chemical Company, Inc. | High-purity carboxylic acid ester and method for producing same |
| JPWO2017057320A1 (en) * | 2015-10-02 | 2018-07-19 | 三菱瓦斯化学株式会社 | High purity carboxylic acid ester and method for producing the same |
| WO2017057320A1 (en) * | 2015-10-02 | 2017-04-06 | 三菱瓦斯化学株式会社 | High-purity carboxylic acid ester and method for producing same |
| TWI698425B (en) * | 2015-10-02 | 2020-07-11 | 日商三菱瓦斯化學股份有限公司 | Method for manufacturing high-purity carboxylic acid ester |
| CN109160876A (en) * | 2018-11-06 | 2019-01-08 | 湖南东为化工新材料有限公司 | A kind of preparation method of electronic grade cyclohexanone |
| CN109160876B (en) * | 2018-11-06 | 2022-04-15 | 湖南东为化工新材料有限公司 | Preparation method of electronic grade cyclohexanone |
| CN109455683A (en) * | 2018-11-23 | 2019-03-12 | 宜宾海丰和锐有限公司 | A method of purifying hydrazine hydrate prepares electron level hydrazine hydrate |
| CN109970555A (en) * | 2018-12-28 | 2019-07-05 | 深圳光华伟业股份有限公司 | The preparation method of electron level n propyl propionate |
| CN113004119A (en) * | 2019-12-19 | 2021-06-22 | 安集微电子（上海）有限公司 | Preparation method of electronic-grade reagent |
| CN112898154A (en) * | 2021-01-21 | 2021-06-04 | 宁波南大光电材料有限公司 | Method for removing water in ethyl lactate |
| CN112920161A (en) * | 2021-01-27 | 2021-06-08 | 宁波南大光电材料有限公司 | Electronic-grade dioxane and preparation method thereof |
| WO2022241690A1 (en) * | 2021-05-19 | 2022-11-24 | Dow Global Technologies Llc | Processes for purifying organic amines |
| CN115353121A (en) * | 2022-09-01 | 2022-11-18 | 阜新泽程化工有限责任公司 | Industrial production method of electronic pure ammonium sulfite |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104610061B (en) | 2016-09-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104610061A (en) | Preparation method of electronic ethyl lactate | |
| CN101307456B (en) | Pickling waste acid regeneration process | |
| CN102070162B (en) | Method for extracting lithium from salt lake brine | |
| CN105289493A (en) | Ferromanganese modified straw active carbon adsorbent for As (III) adsorption, and applications thereof | |
| CN105152191A (en) | Method for preparing lithium carbonate through salt lake brine with high ratio of magnesium to lithium | |
| CN109160876B (en) | Preparation method of electronic grade cyclohexanone | |
| CN103553138A (en) | Comprehensive utilization method for separating, concentrating and purifying manganese sulfate, magnesium sulfate and calcium sulfate in high-salt waste water | |
| CN102417194A (en) | Method for deeply removing magnesium through chelating resin for extracting lithium from salt lake brine | |
| CN105967424A (en) | Method for recycling rare earth extraction residual wastewater with high sodium salt content | |
| CN105016368A (en) | Iron-containing aluminum chloride solution iron removal method | |
| CN105177288A (en) | Method for preparing lithium hydroxide from salt lake brine with high magnesium-lithium ratio | |
| CN103553256A (en) | Recycling treatment process for chlorohydric acid pickling liquid waste | |
| CN109251143A (en) | The preparation method of electron level ethyl lactate | |
| CN202654912U (en) | Device for recycling phosphoric acid in active carbon tail gas by using phosphoric acid way | |
| CN206204081U (en) | A kind of phenmethylol produces the circulation production device of wastewater utilization | |
| CN103408082A (en) | Recovery method and device for formic acid solvent during metronidazole production | |
| CN103819042B (en) | A kind of hydrochloride waste purifying treatment method | |
| CN108128834B (en) | Chromium adsorbent and preparation method and application thereof | |
| CN104150667B (en) | A kind of recycling processing method of hot-rolled sheet surface cleaning spent acid solution | |
| CN104711617A (en) | Regeneration method of acid washing waste acids | |
| CN203461817U (en) | High-purity chlorine gas rectification device | |
| CN102627337B (en) | Equipment capable of treating high-difficult waste water and enabling waste water to be directly recycled | |
| CN204841334U (en) | Crystal system ammonia nitrogen recovery unit | |
| CN205328617U (en) | Device of dirty sour concentrated defluorinate chlorine | |
| CN104689791A (en) | Preparation and modification methods for solid material Zr-CN for adsorbing CO2 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |