CN101012164B - Device and method of refining and separating acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system - Google Patents
Device and method of refining and separating acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system Download PDFInfo
- Publication number
- CN101012164B CN101012164B CN2006101306471A CN200610130647A CN101012164B CN 101012164 B CN101012164 B CN 101012164B CN 2006101306471 A CN2006101306471 A CN 2006101306471A CN 200610130647 A CN200610130647 A CN 200610130647A CN 101012164 B CN101012164 B CN 101012164B
- Authority
- CN
- China
- Prior art keywords
- tower
- aceticanhydride
- boiling
- low
- point substance
- 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.)
- Expired - Fee Related
Links
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a finishing method of acetic anhydride, which comprises the following parts: low-boiler separating tower, acetic anhydride treating column, preheater, condenser, reflux tank, reboiler and product tank, wherein the feed hole is set on the middle part of low-boiler separating tower with top separating low-boiling point product; the outlet pipe line of rought acetic anhydride on the bottom enters into middle part of acetic anhydride treating column.
Description
Technical field
The invention belongs to the device and method of chemical separation process, relate to a kind of process for purification of aceticanhydride, is exactly the refining tripping device and the method for acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system specifically.
Background technology
Aceticanhydride is called acetic anhydride again; it is a kind of water white liquid, has irritating smell, strong tearing property etc. is arranged; and be a kind of important Organic Chemicals; chemical property is very active, is widely used in the production of cellulose acetate and as the acetylizing agent in medicine, dyestuff, spices and the organic synthesis.The technology of producing aceticanhydride in the The modern industry mainly contains oxidation of acetaldehyde co-production method, ketene process and ritalin oxo synthesis.The oxidation of acetaldehyde co-production method has that flow process is simple, technical maturity but its corrosion of equipment is serious, energy consumption is bigger; Though the ketene process technology maturation, its flow process complexity and side reaction are more, and process energy consumption and facility investment are all bigger; The gas phase oxo process and the liquid phase carbonyl synthesis method of Recent study exploitation have the advantages that flow process is simple, the process energy consumption is lower, side reaction is less and three waste discharge is few, and can realize the flow process of coproduction by acetic acid and aceticanhydride, be a kind of environmental protection technology efficiently, we can say the modern technique that on behalf of the target aceticanhydride, this method produce.
Ritalin (CH
3COOCH
3) with the reaction process of the synthetic aceticanhydride of carbon monoxide (CO) liquid phase carbonyl be:
CH
3COOCH
3+CO→(CH
3CO)
2O
Contain methyl alcohol (CH in the final reacting product of this synthesis technique
3OH), ritalin (CH
3COOCH
3), acetic acid (CH
3COOH) and aceticanhydride (CH3CO)
2O, its content is respectively about 8.0%, 9.0%, 16.0% and 70.0%.Reaction system methyl alcohol and ritalin are low-boiling compound and form azeotrope that acetic acid and aceticanhydride are higher-boiling compound; Acetic acid and aceticanhydride are had relatively high expectations to the corrosion of material in addition, this also corresponding difficulty that increases separating technology equipment.Traditional separating technology just separates methyl alcohol, ritalin and acetic acid simply as low-boiling compound, and then rectifying separation aceticanhydride, just need high theoretical plate number so that will separate acetic acid and the aceticanhydride mixing system that boiling point is more or less the same fully, and the relevant device of rectifier unit is perishable so that the separation purity of target product aceticanhydride does not often reach requirement.In order to solve equipment corrosion problem in the aceticanhydride sepn process, whole flow sheet equipment just all adopts the titanium material without detailing, has caused the huge waste of investment.Just report some relevant rectifying separation in the present domestic and foreign literature, rarely had the energy highly efficient distilling to separate the process for refining report of liquid phase oxo-acetic anhydride product.
Technology of the present invention is exactly at each character of forming of aceticanhydride reaction raw materials liquid in ritalin and the carbon monoxide liquid phase carbonyl synthetic vinegar anhydride reactant technology, the refining technology of separating aceticanhydride of a kind of highly efficient distilling of proposition.
Summary of the invention
The object of the present invention is to provide ritalin and carbon monoxide liquid phase carbonyl to generate system in aceticanhydride (diacetyl oxide) reaction process and separate rectifying separation technology in the aceticanhydride, use rectifying separation technology provided by the invention, flow process is simple, energy consumption is lower and the purity of target product aceticanhydride product separation and the rate of recovery are very high.
Liquid phase carbonyl of the present invention generates the tripping device of aceticanhydride in the aceticanhydride reaction system, comprise low-boiling-point substance knockout tower, aceticanhydride treating tower, preheater, condenser, return tank, reboiler and product jar, wherein opening for feed is arranged on low-boiling-point substance knockout tower middle part, low-boiling-point substance knockout tower cat head separates the lower boiling product, and thick aceticanhydride discharging pipeline connection enters aceticanhydride treating tower middle part at the bottom of the tower.
Employing low-boiling-point substance knockout tower provided by the invention separates the rectifying separation device of aceticanhydride with aceticanhydride treating tower two towers, comprise that aceticanhydride stock liquid 1, aceticanhydride stock liquid storage tank 2, microprocessor pump drive 3 and raw material feed preheater 13 are formed feed systems, the lower boiling knockout tower is made up of low-boiling-point substance knockout tower 4, condenser 5, return tank 6, reboiler 8 and lower boiling product jar 7 and by aceticanhydride treating tower 9, condenser 5, return tank 6, reboiler 8, acetate products jar 11, aceticanhydride product jar 10 and the aceticanhydride treating tower formed of aceticanhydride feed preheater 12 slightly.Wherein aceticanhydride stock liquid 1 at first connects aceticanhydride storage tank 2, connect raw material feed preheater 13 by microprocessor pump drive 3 then and enter low-boiling-point substance knockout tower 4 middle parts, cat head is connected with return tank 6 after connecting condenser 5 again, wherein its reflux pipeline one end is connected in rectifying tower top, and the other end is connected with lower boiling product jar 7; An end is connected with reboiler at the bottom of the tower, and the other end is connected with thick aceticanhydride feed preheater 12 and enters aceticanhydride treating tower 9 middle parts again; Same cat head connects condenser 5 and return tank 6 successively, and wherein reflux pipeline one end is connected in rectifying tower top, and the other end is connected with acetate products jar 11; Be connected with thick aceticanhydride feed preheater 12 with reboiler 8 respectively too at the bottom of the tower, and then connect raw material feed preheater 13 and aceticanhydride product jar 10 successively.
The material of described low-boiling-point substance knockout tower is stainless steel 316L, and above tower body of aceticanhydride treating tower opening for feed and column internals are stainless steel 316L, and following tower body of opening for feed and column internals are the titanium material.The aspect ratio of low-boiling-point substance knockout tower is 25/1～30/1, and the aspect ratio of aceticanhydride treating tower is 25/1～30/1.In the low-boiling-point substance separation Tata high efficiency packing or sieve-tray tower are housed; Be filled with efficient structured packing or sieve-tray tower, bubble-plate column, guide float valve tray in the refining Tata of aceticanhydride.
Aceticanhydride reaction raw materials liquid is by entering the low-boiling-point substance knockout tower with aceticanhydride product distillate through behind the preheating heat exchanger, and inlet temperature of stabilizer is 60.0～62.0 ℃ after the heat exchange; Enter the aceticanhydride treating tower behind the feed liquid that is rich in acetic acid and aceticanhydride of extraction and the aceticanhydride distillate interchanger at the bottom of the low-boiling-point substance separation Tata, inlet temperature of stabilizer is 90.0～92.0 ℃ after the heat exchange.
Liquid phase carbonyl of the present invention generates the working method of the tripping device of aceticanhydride in the aceticanhydride reaction system, low-boiling-point substance knockout tower operational condition is: the cat head working pressure is 100.0～105.0kPa, working pressure is 120.0～125.0kPa at the bottom of the tower, reflux ratio is 1.5/1～3/1, tower top temperature is 60.0～62.0 ℃, and column bottom temperature is 116.0～120.0 ℃; The operational condition of aceticanhydride treating tower is: tower top pressure is 40.0～45.0kPa, and working pressure is 70.0～75.0kPa at the bottom of the tower, and reflux ratio is 2/1～4/1, and tower top temperature is 85.0～90.0 ℃, and column bottom temperature is 105.0～110.0 ℃.
Specifically liquid phase carbonyl generates the working method of the tripping device of aceticanhydride in the aceticanhydride reaction system, and step is as follows:
1). aceticanhydride reaction raw materials liquid 1 at first adds aceticanhydride stock liquid storage tank 2, enters low-boiling-point substance knockout tower 4 middle parts by liquid feeding transferpump 3 through preheater 13, and cat head carries out condensation with condenser 5, adopts reboiler 8 that tower internal heating steam is provided at the bottom of the tower;
2). in the low-boiling-point substance knockout tower 4 in the stock liquids steam of low-boiling compound methyl alcohol and ritalin through condenser 5 to return tank 6, part phlegma is back in the tower, and the mixture of a part of extraction low-boiling compound methyl alcohol and ritalin is to putting into lower boiling waste tank 7;
3). enter aceticanhydride treating tower 9 from the mixture that is rich in acetic acid and aceticanhydride of low-boiling-point substance knockout tower 4 bottom extraction through interchanger 12, cat head adopts condenser 5 to carry out condensation, adopts reboiler 8 that tower internal heating steam is provided at the bottom of the tower;
4). from the steam of the refining cat head of aceticanhydride through condenser 5 to return tank 6, part phlegma is back in the tower, another part extraction purity greater than 99.0% acetic acid to acetate products jar 11, its tower bottom extraction purity greater than 99.0% aceticanhydride to aceticanhydride product jar 13.
Rectifying separation technology of the present invention, its thermal coupling heat exchange by preheating heat exchanger, thick aceticanhydride feed preheater and the refining bottom product of aceticanhydride has made full use of the thermal exchange of process, with respect to traditional aceticanhydride rectifying separation technology, the process total energy consumption reduces about about 30.0%.
The present invention is cross-linked tower system configuration of being made up of low-boiling-point substance knockout tower and aceticanhydride treating tower and the integrated isolation technique of forming in conjunction with following operational condition of thermal coupling: the mixture that contains ritalin, methyl alcohol, acetic acid and aceticanhydride enters the middle part that enters the low-boiling-point substance knockout tower behind the feed preheater by transferpump, high efficiency packing or tray column are housed, lower boiling methyl alcohol of cat head extraction and ritalin in the tower; The mixture that comprises acetic acid and aceticanhydride that tower bottom flow goes out enters the aceticanhydride treating tower.
Using an advantage of the present invention is exactly to consider the physicochemical property of aceticanhydride raw material system, is chosen to be 316L and high-performance titanium material with what whole separation process equipment adopted, has solved the problem of material corrosion resistance nature in the aceticanhydride separating technology fully.
Another advantage of the present invention is exactly to utilize aceticanhydride feed purification separating technology in the liquid phase carbonyl synthetic vinegar anhydride reactant system to solve the problem of effectively refining oxo-acetic anhydride reaction solution, and the rectifying separation technical process of invention is simple, the process energy consumption is less, for the technology of the synthetic aceticanhydride of its liquid phase carbonyl is applied the advantage that provides certain, and have favorable economic benefit and social benefit.
The invention has the advantages that and pass through appropriate design, adopt the low-boiling-point substance knockout tower to separate the separating technology of aceticanhydride feed liquid in the liquid phase oxo-acetic anhydride reaction process with the aceticanhydride treating tower, can obtain quality purity greater than the high-grade aceticanhydride more than 99.0%, whole technology separation process is simple, investment is less relatively and have that energy consumption is lower, aceticanhydride purity is than characteristics such as height, is a kind of efficient feasible aceticanhydride rectifying separation technology.Cat head extraction acetic acid can be recycled, and can obtain quality purity at the bottom of the tower greater than the aceticanhydride more than 99.0%, and whole process purified aceticanhydride purity is greater than 99.0%, and the rate of recovery is greater than 98.5%.
Description of drawings
Fig. 1 is an aceticanhydride process for refining schema in the ritalin liquid phase carbonyl synthetic vinegar anhydride reactant process.
Embodiment
Below in conjunction with embodiment the present invention is further elaborated, but the present invention is not produced any restriction.
| Embodiment 1: | Embodiment 2: | Embodiment 3: | |
| The low-boiling-point substance knockout tower | Tower body and column internals material: 316L tower height: 3.0m tower diameter: 100mm aspect ratio: 30/1 column internals: efficient Mellapak packing tower top pressure: 102 ± 0.1kPa tower bottom pressure: 122 ± 0.1kPa tower top temperature: 60.5 ℃ of column bottom temperatures: 119.0 ℃ of reflux ratios: 2/1 raw material inlet amount: 10.0kg/hr aceticanhydride mass percent: 70.0% | Tower body and column internals material: 316L tower height: 3.2m tower diameter: 120mm aspect ratio: 25/1 column internals: guide float-valve tower tray tower top pressure: 100.8kPa tower bottom pressure: 120 ± 0.1kPa tower top temperature: 61.5 ℃ of column bottom temperatures: 118.0 ℃ of reflux ratios: 2.5/1 raw material inlet amount: 12.0kg/hr aceticanhydride mass percent: 70.5% | Tower body and column internals material: 316L tower height: 3.6m tower diameter: 120mm aspect ratio: 30/1 column internals: sieve-tray tower tower top pressure: 105 ± 0.1kPa tower bottom pressure: 124 ± 0.1kPa tower top temperature: 60.8 ℃ of column bottom temperatures: 120.0 ℃ of reflux ratios: 3/1 raw material inlet amount: 15.0kg/hr aceticanhydride mass percent: 70.2% |
| Embodiment 1: | Embodiment 2: | Embodiment 3: | |
| The aceticanhydride treating tower | Tower body and column internals material: 316L and titanium material tower height: 2.8m tower diameter: 100.0mm aspect ratio: 28/1 column internals: efficient Mellapak packing column overhead pressure: 41.0 ± 0.1kPa tower bottom pressure: 71.0 ± 0.1kPa tower top temperature: 85.5 ℃ of column bottom temperatures: 109.0 ℃ of reflux ratios: 3/1 raw material inlet amount: 8.0kg/hr aceticanhydride mass percent: 99.10% | Tower body and column internals material: 316L and titanium material tower height: 3.6m tower diameter: 120.0mm aspect ratio: 30/1 column internals: guide float-valve tower tray tower top pressure: 42.0 ± 0.1kPa tower bottom pressure: 72.0 ± 0.1kPa tower top temperature: 85.8 ℃ of column bottom temperatures: 109.2 ℃ of reflux ratios: 3/1 raw material inlet amount: 8.4kg/hr aceticanhydride mass percent: 99.12% | Tower body and column internals material: 316L and titanium material tower height: 3.6m tower diameter: 120.0mm aspect ratio: 30/1 column internals: sieve-tray tower tower top pressure: 41.6 ± 0.1kPa tower bottom pressure: 72.2 ± 0.1kPa tower top temperature: 90.0 ℃ of column bottom temperatures: 110.0 ℃ of reflux ratios: 3.5/1 raw material inlet amount: 10.5kg/hr aceticanhydride mass percent: 99.11% |
| Aceticanhydride purity: 99.23% (wt%) | Aceticanhydride purity: 99.21% (wt%) | Aceticanhydride purity: 99.14% (wt%) | |
| The aceticanhydride rate of recovery: 99.10% | The aceticanhydride rate of recovery: 99.12% | The aceticanhydride rate of recovery: 99.11% |
The refining tripping device and the method for the acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system that the present invention proposes, be described by preferred embodiment, person skilled obviously can be in not breaking away from content of the present invention, spirit and scope to equipment as herein described and the preparation method changes or suitably change realize the technology of the present invention with combination.Special needs to be pointed out is, the replacement that all are similar and change apparent to those skilled in the artly, they are regarded as being included in spirit of the present invention, scope and the content.
Claims (4)
1. a liquid phase carbonyl generates the tripping device of aceticanhydride in the aceticanhydride reaction system, comprises low-boiling-point substance knockout tower, aceticanhydride treating tower, preheater, condenser, return tank, reboiler and product jar; It is characterized in that opening for feed is arranged on low-boiling-point substance knockout tower middle part, low-boiling-point substance knockout tower cat head separates the lower boiling product, and thick aceticanhydride discharging pipeline connection enters aceticanhydride treating tower middle part, tower bottom extraction aceticanhydride at the bottom of the tower; The material of low-boiling-point substance knockout tower is stainless steel 316L, and above tower body of aceticanhydride treating tower opening for feed and column internals are stainless steel 316L, and following tower body of opening for feed and column internals are the titanium material.
2. the liquid phase carbonyl of claim 1 generates the working method of the tripping device of aceticanhydride in the aceticanhydride reaction system, it is characterized in that: aceticanhydride reaction raw materials liquid is by entering the low-boiling-point substance knockout tower with aceticanhydride product distillate through behind the preheating heat exchanger, and inlet temperature of stabilizer is 60.0～62.0 ℃ after the heat exchange; Enter the aceticanhydride treating tower behind the feed liquid that is rich in acetic acid and aceticanhydride of extraction and the aceticanhydride distillate interchanger at the bottom of the low-boiling-point substance separation Tata, inlet temperature of stabilizer is 90.0～92.0 ℃ after the heat exchange.
3. described working method as claimed in claim 2, it is characterized in that, low-boiling-point substance knockout tower operational condition is: the cat head working pressure is 100.0～105.0kPa, working pressure is 120.0～125.0kPa at the bottom of the tower, reflux ratio is 1.5/1～3/1, tower top temperature is 60.0～62.0 ℃, and column bottom temperature is 116.0～120.0 ℃; The operational condition of aceticanhydride treating tower is: tower top pressure is 40.0～45.0kPa, and working pressure is 70.0～75.0kPa at the bottom of the tower, and reflux ratio is 2/1～4/1, and tower top temperature is 85.0～90.0 ℃, and column bottom temperature is 105.0～110.0 ℃.
4. working method as claimed in claim 3, its feature is as follows:
1). aceticanhydride reaction raw materials liquid (1) at first adds aceticanhydride stock liquid storage tank (2), liquid feeding transferpump (3) enters low-boiling-point substance knockout tower (4) middle part through preheater (13) then, cat head adopts condenser (5) to carry out condensation, adopts reboiler (8) that tower internal heating steam is provided at the bottom of the tower;
2). in the interior stock liquid of low-boiling-point substance knockout tower (4) steam of low-boiling compound methyl alcohol and ritalin through condenser (5) to return tank (6), part phlegma is back in the tower, and the mixture of a part of extraction low-boiling compound methyl alcohol and ritalin is to putting into lower boiling waste tank (7);
3). enter aceticanhydride treating tower (9) from the mixture that is rich in acetic acid and aceticanhydride of low-boiling-point substance knockout tower (4) bottom extraction through interchanger (12), cat head adopts condenser (5) to carry out condensation, adopts reboiler (8) that tower internal heating steam is provided at the bottom of the tower;
4). from the steam of the refining cat head of aceticanhydride through through condenser (5) to return tank (6), part phlegma is back in the tower, another part extraction purity greater than 99.0% acetic acid to acetate products jar (11), its tower bottom extraction purity greater than 99.0% aceticanhydride to aceticanhydride product jar (13).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2006101306471A CN101012164B (en) | 2006-12-28 | 2006-12-28 | Device and method of refining and separating acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2006101306471A CN101012164B (en) | 2006-12-28 | 2006-12-28 | Device and method of refining and separating acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101012164A CN101012164A (en) | 2007-08-08 |
| CN101012164B true CN101012164B (en) | 2010-08-11 |
Family
ID=38699909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2006101306471A Expired - Fee Related CN101012164B (en) | 2006-12-28 | 2006-12-28 | Device and method of refining and separating acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101012164B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7981256B2 (en) * | 2007-11-09 | 2011-07-19 | Uop Llc | Splitter with multi-stage heat pump compressor and inter-reboiler |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1116617A (en) * | 1994-04-04 | 1996-02-14 | 代科化学工业株式会社 | Process for producing acetic anhydride and acetic acid |
| CN1520920A (en) * | 2003-01-30 | 2004-08-18 | 西南化工研究设计院 | Technique for recovering useful constituent from the tail gas arising from acetic acid synthesis process from carbonyl |
| CN1651388A (en) * | 2004-02-04 | 2005-08-10 | 上海吴泾化工有限公司 | Recovery method of tail gas light component in carbonylation production of acetic acid lanhydride |
-
2006
- 2006-12-28 CN CN2006101306471A patent/CN101012164B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1116617A (en) * | 1994-04-04 | 1996-02-14 | 代科化学工业株式会社 | Process for producing acetic anhydride and acetic acid |
| CN1520920A (en) * | 2003-01-30 | 2004-08-18 | 西南化工研究设计院 | Technique for recovering useful constituent from the tail gas arising from acetic acid synthesis process from carbonyl |
| CN1651388A (en) * | 2004-02-04 | 2005-08-10 | 上海吴泾化工有限公司 | Recovery method of tail gas light component in carbonylation production of acetic acid lanhydride |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101012164A (en) | 2007-08-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101357890B (en) | Methyl carbonate synthesis and refining technique using heat pump technique and apparatus thereof | |
| KR101583331B1 (en) | Process for preparing cyclohexanol and cyclohexanone by cyclohexane oxidation, and device for same | |
| WO2021047042A1 (en) | Reaction system and process for preparing butanol and octanol based on microinterface-enhanced carbonylation of propylene | |
| US20110144378A1 (en) | Catalytic reaction-rectification integrated process and specialized device thereof | |
| CN105037094B (en) | A kind of energy coupling rectificating method of acetate preparation of ethanol by hydrogenating | |
| CN110862301B (en) | Sec-butyl alcohol refining method and device | |
| CN106518640A (en) | High efficiency separation and refinement method of cyclohexanone product | |
| CN103130611A (en) | Neopentyl glycol condensation hydrogenation production process and device thereof | |
| WO2020029753A1 (en) | Production process of 2,2-dimethyl-1,3-propanediol | |
| CN105669379B (en) | A kind of technique of ethyl acetate preparation of ethanol through hydrogenation | |
| CN112299979A (en) | Method for extracting isobutyraldehyde | |
| CN101589015A (en) | Produce acrylic acid | |
| CN101704733B (en) | New hydrolysis coupling process of methyl acetate and special device thereof | |
| CN109748791B (en) | Energy-saving method for producing dimethyl adipate | |
| CN208182888U (en) | Reactive distillation-film device coupling production ethyl acetate in high purity device | |
| CN101012164B (en) | Device and method of refining and separating acetic anhydride of liquid phase carbonyl generation acetic anhydride reaction system | |
| CN216170039U (en) | Energy-saving and carbon-reducing mixed butyraldehyde separation system | |
| CN110759808A (en) | Production process and production system of 1, 3-butanediol | |
| CN101670187B (en) | External reflux device of phenol mixed rectification system and application thereof | |
| CN103254042B (en) | Technique for synthesizing dimethyl ether | |
| CN110878006B (en) | Method and device for separating ethanol and ethyl acetate | |
| CN202336224U (en) | Azeotropic distillation system for mixture of carbinol and tetrahydrofuran | |
| CN1166616C (en) | Process and apparatus for purifying raw lactic acid | |
| CN101851152A (en) | Method for preparing dimethyl ether by methyl alcohol gaseous phase dehydration | |
| CN108863794A (en) | A kind of preparation method and device of the secondary butyl ester of high-purity acetic acid |
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 | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20100811 Termination date: 20131228 |