CN102249916B - Continuous production process for tributyl citrate - Google Patents
Continuous production process for tributyl citrate Download PDFInfo
- Publication number
- CN102249916B CN102249916B CN201110138013.1A CN201110138013A CN102249916B CN 102249916 B CN102249916 B CN 102249916B CN 201110138013 A CN201110138013 A CN 201110138013A CN 102249916 B CN102249916 B CN 102249916B
- Authority
- CN
- China
- Prior art keywords
- tributyl citrate
- membrane
- catalyst
- propyl carbinol
- continuous production
- 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.)
- Active
Links
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a continuous production process for tributyl citrate, in particular to a continuous production process for refining the tributyl citrate by a membrane separation technology, and belongs to the technical field of chemical engineering. In esterification, a solid acid catalyst with the granularity of 10 to 100nm is adopted and has high activity and high reaction speed. The traditional neutralization washing, catalyst separation and reduced pressure dealcholization process is improved by the membrane separation technology, the whole technological process is continuously and automatically operated, the production efficiency is high, the product quality is stable. The catalyst separation process and the esterification process are coupled in the same system, and the problem that a fine suspended catalyst is seriously lost in the separating and recycling process is solved. By membrane separation, the energy consumption is low and the recovery efficiency of butanol is high. The equipment investment is small, and the process is suitable for large-scale production.
Description
Technical field
The present invention relates to a kind of continuous production technology of tributyl citrate, especially a kind of continuous production technology with the refining tributyl citrate of membrane separation technique, belongs to technical field of chemical engineering.
Background technology
Tributyl citrate (being called for short TBC) is as a kind of novel " green " environmentally-friendly plastic softening agent, have nonpoisonous and tasteless, consistency good, plasticizing efficiency is high, be easily biodegradable and the advantage such as volatility is little, winter hardiness, photostabilization and have excellent water-resistance, and in resin, there is anti-fungi performance, alternative phthalate conventional plasticizers.Therefore TBC is widely used in the fields such as food and medical instrumentation package, makeup, daily necessities, toy, personal hygiene article, is also important chemical intermediate simultaneously.
Under the effect that traditional TBC production technique is is generally catalyzer by citric acid and propyl carbinol at the vitriol oil, esterification is synthesized, and the aftertreatment of reaction product will be dewatered through alkali neutralization, washing, distillation dealcoholysis, decolouring finally obtain finished product.Its reaction principle is shown in reaction equation below.
Adopting traditional technology to produce tributyl citrate, although quality product is more stable, can be up to state standards, also there is obvious defect in the method for this production tributyl citrate, as:
Although 1. sulfuric acid low price, catalytic activity is high, and it exists a lot of shortcomings: the production cycle is long, low conversion rate; And due to dehydration, esterification and the oxygenizement of sulfuric acid, by product is many, this is to the refining of reaction product and reclaim and all bring difficulty; In addition, sulfuric acid is severe corrosion equipment also, increases production cost.
2. the aftertreatment of traditional technology mainly comprises the steps such as neutralization, washing, decompression dealcoholysis, decolouring press filtration, belongs to periodical operation, and process is discontinuous, and labour intensity is larger; Alkali neutralizes, washes and remove the sulfuric acid as catalyzer, causes complex process, produces wastewater flow rate large, and separation efficiency is low, causes product to run off; Underpressure distillation dealcoholysis energy consumption is higher, just can reach requirement through multistage dealcoholysis, complicated operation, and separation efficiency is low, and long flow path produces the three wastes more; Device has high input, and industrial scale is little, has reduced production efficiency.
Adopt solid acid catalyst to replace vitriol oil synthesizing citric acid tri-n-butyl, can solve liquid acid pollution of ecological environment, etching apparatus and harm production operation safety problem in esterification technique.Generally, granules of catalyst is thinner, and speed of reaction is faster, but the separation of small grain size catalyzer is more difficult.The separation methods such as traditional gravity settling, centrifugation, flotation, cake filtration, Depth Filtration all can not effectively be separated it completely from liquid-phase product, cause catalyst loss serious, and can affect the purity of product.
In addition; country is more and more higher for restriction and the environmental protection requirement of softening agent; for this reason; in the urgent need to the traditional technology of producing tributyl citrate is reformed; work out as early as possible a kind of production technique newly, rational, advanced, environmental protection, to meet the heavy demand of the outer market of Now Domestic to tributyl citrate.
Summary of the invention
The object of this invention is to provide a kind of continuous production technology of tributyl citrate, can successfully adopt mineral membrane isolation technique to realize product purification by this technique, the separation that can effectively solve subparticle solid catalyst, can improve dealcoholysis and dewatering efficiency; Can also improve product purity, reduce energy consumption, reduce wastewater discharge, continuous automatic production, raises the efficiency simultaneously, strengthens industrial scale.
Technical scheme of the present invention is:
A continuous production technology for tributyl citrate, is characterized in that comprising step:
(1) esterification of citric acid and butanols: citric acid, propyl carbinol and solid catalyst are added in reactor according to a certain percentage, carry out esterification under conventional reaction process condition.
Wherein, described solid catalyst be interpreted as any in prior art can catalysis citric acid and the solid catalyst of propyl carbinol generation esterification.In the present invention, described solid catalyst is solid acid, includes but not limited to molecular sieve catalyst, super acidic catalyst and heteropolyacid catalyst; The particle diameter of catalyzer is 10～100 nm.
Described citric acid and the mol ratio of propyl carbinol are 1:4～1:6; It is 1%～3% that described solid catalyst accounts for citric acid mass percent; Described enzymatic synthesis condition is: at 100～140 DEG C, react 2～4 hours.
(2) in embrane method and washing: after esterification finishes, add in alkaline solution and after, leave standstill and make ester water stratification, getting upper strata ester layer adds water continuously and enters together hydrophilic porous membrane module, carry out aqueous phase separation, until ester layer is washed till to neutrality, obtain holding back the concentrated material of survey, mainly comprise propyl carbinol, tributyl citrate and catalyzer; Per-meate side separates water outlet to wastewater treatment.
Wherein, described alkaline solution is sodium carbonate, sodium hydroxide or potassium hydroxide solution, and concentration is 3%～5%.
Described hydrophilic porous membrane module is tubular type mineral membrane; It is symmetry or the asymmetric membrane of pottery, metal or its matrix material formation of 5～500 nm that described mineral membrane adopts mean pore size; Single tube or hyperchannel all can.
Described membrane sepn operating parameters is: cross-flow velocity 1～5 m/s, working pressure 0.1～0.5 MPa.
(3) embrane method catalyst separating: the concentrated material of holding back side enters lipophilicity porous-membrane module and carries out solid-liquid separation, and wherein propyl carbinol and tributyl citrate are separated through per-meate side, the solid catalyst of holding back reclaims.
Wherein, described lipophilicity porous-membrane module is modified ceramic film, and it is symmetry or the asymmetric membrane of the pottery formation of 5～500 nm that ceramic membrane adopts mean pore size; Single tube or hyperchannel all can; The modification of ceramic membrane used adopts organo silane coupling agent to carry out chemical modification to ceramic membrane, and water droplet is 90～170 degree at the contact angle on film surface.
Described membrane sepn operating parameters is: cross-flow velocity 1～7m/s, working pressure 0.1～0.6 MPa.
(4) infiltration evaporation dealcoholysis: the mixture of propyl carbinol and tributyl citrate is delivered into infiltration vaporization membrane module, and propyl carbinol is isolated and reclaimed from per-meate side, obtains concentrated tributyl citrate.
Wherein, the supporting layer of described infiltrating and vaporizing membrane is aluminum oxide, and separating layer is polydimethylsiloxane.
(5) decolouring press filtration obtains tributyl citrate.
Beneficial effect of the present invention is:
1. the present invention has realized the continuous operation of whole technological process, and level of automation is high, and labour intensity is little, easy to operate, and production efficiency is high.
2. the present invention has realized continuous operation, has solved the separation problem of fine suspended state catalyzer in esterification, and " reaction-separation-reuse " of catalyzer can be carried out continuously; Technique is succinct, and facility investment is few, has reduced the loss of catalyzer, and production can be carried out continuously, enhances productivity.
3. the present invention adopts nanoscale solids acid catalyst, has accelerated speed of response, Reaction time shorten, and esterification yield reaches more than 97% simultaneously.
4. the present invention adopts in embrane method and washing process, and separation efficiency is high, can serialization move, and little compared with traditional technology wastewater discharge, environmental pollution is little.
5. the present invention adopts infiltration evaporation to remove butanols, and energy consumption is low, pollution-free, meets environmental requirement, and separation efficiency is high, and operation is simple continuously, and has realized " reclaiming-recycling " continuous process of butanols.
6. the tributyl citrate product performance that the present invention obtains are stable, Functionality, quality and appealing design.
7. membrane separation unit facility investment of the present invention is little, and energy consumption is low, easily forms large-scale production.
Brief description of the drawings
Fig. 1 is the operational flowchart of tributyl citrate continuous production technology of the present invention.
Embodiment
Below in conjunction with brief description of the drawings embodiments of the present invention.
embodiment 1
1, esterification step
Citric acid and propyl carbinol are dropped in reactor according to the mol ratio of 1:4.5, add 1.5%(to account for the mass percent of citric acid) solid super acid catalyst 50 nm, close dog-house, open chuck heating steam valve, control steam < 0.6 MPa(gauge pressure).Note water outlet situation, strict control still internal pressure (gauge pressure) < 0.015 MPa, in order to avoid cause punching material, the control of reaction top temperature is less than 120 DEG C, reaction reaches 2 hours, get final product sample examination, then sample once per half an hour, when the acid number of thick ester liquid is less than 0.02 mg KOH/g, can think that esterification finishes, close chuck heating steam valve, close reverse flow valve, stop stirring.Open reactor condenser cooling.
2, in embrane method and washing step
After completion of the reaction, the resultant of reaction material pump that is mixed with catalyzer is exported, after metering, material enters neutralization tank, with 3% Na
2cO
3alkaline solution neutralization, then leaves standstill and makes ester water stratification, and water is in the bottom of neutralization tank, by putting into and water collecting tank after metering.Ester layer is exported by pump, and adds continuously washing simultaneously, enters together hydrophilic porous ceramic film component, carries out aqueous phase separation, is washed till neutrality.The concentrated material of holding back side mainly comprises propyl carbinol, tributyl citrate and catalyzer, enters relay tank 1 and regulates pressure, and per-meate side is isolated water to wastewater collection tank.Adopting aperture is the tubular ceramic membrane of 0.03 μ m, 19 passages, passage internal diameter 4 mm, cross-flow velocity 1m/s, working pressure 0.4 MPa, membrane permeation flux 0.5m
3m
-2h
-1.
3, embrane method catalyst separating operation
Material in relay tank 1 enters close Organic Compound porous ceramics membrane module via pump, and wherein propyl carbinol and tributyl citrate are separated and entered relay tank 2 through per-meate side.Catalyzer is trapped, and in the time being concentrated to solid content and reaching 15%, sepn process completes, and returns to esterifying kettle for lower secondary response.Adopt aperture be the ceramic membrane of 0.02 μ m, 7 passages, and the modification of ceramic membrane used adopt organo silane coupling agent ceramic membrane is carried out to chemical modification, water droplet the contact angle on film surface be 90～170 degree; Passage internal diameter 6mm, cross-flow velocity 1m/s, working pressure 0.3MPa, membrane permeation flux 0.1m
3m
-2h
-1.
4, infiltration evaporation dealcoholysis operation and decolouring press filtration operation
Material in relay tank 2 enters infiltration vaporization membrane module by pump delivery, and propyl carbinol is preferentially separated, and returns to esterifying kettle and continues recycle, and concentrated tributyl citrate is packaged to be finished product through decolouring, press filtration.The yield of tributyl citrate is 97.5%.Adopt polydimethylsiloxane (PDMS)/aluminum oxide infiltrating and vaporizing membrane, working pressure 0.2 MPa, membrane permeation flux 4kgm
-2h
-1.
embodiment 2
1, esterification step
Citric acid and propyl carbinol are dropped in reactor according to the mol ratio of 1:4, add 1%(to account for the mass percent of citric acid) molecular sieve catalyst 10 nm, close dog-house, open chuck heating steam valve, control steam < 0.6 MPa(gauge pressure).Note water outlet situation, strict control still internal pressure (gauge pressure) < 0.015 MPa, in order to avoid cause punching material, the control of reaction top temperature is less than 100 DEG C, reaction reaches 3 hours, sample examination, then samples once per half an hour, when the acid number of thick ester liquid is less than 0.02mgKOH/g, can think that esterification finishes, close chuck heating steam valve, close reverse flow valve, stop stirring.Open reactor condenser cooling.
2, in embrane method and washing step
After completion of the reaction, the resultant of reaction material pump that is mixed with catalyzer is exported, after metering, material enters neutralization tank, with 5% NaOH alkaline solution neutralization, then leaves standstill and makes ester water stratification, and water is in the bottom of neutralization tank, by putting into and water collecting tank after metering.Ester layer is exported by pump, and adds continuously washing simultaneously, enters together hydrophilic porous ceramic film component, carries out aqueous phase separation, is washed till neutrality.The concentrated material of holding back side mainly comprises propyl carbinol, tributyl citrate and catalyzer, enters relay tank 1 and regulates pressure, and per-meate side is isolated water to wastewater collection tank.Adopting aperture is the tube type metal film of 0.005 μ m, 19 passages, passage internal diameter 4mm, cross-flow velocity 5m/s, working pressure 0.1MPa, membrane permeation flux 0.05m
3m
-2h
-1.
3, embrane method catalyst separating operation
Material in relay tank 1 enters close Organic Compound porous ceramics membrane module via pump, and wherein propyl carbinol and tributyl citrate are separated and entered relay tank 2 through per-meate side.Catalyzer is trapped, and in the time being concentrated to solid content and reaching 15%, sepn process completes, and returns to esterifying kettle for lower secondary response.Adopt aperture be the ceramic membrane of 0.5 μ m, 7 passages, and the modification of ceramic membrane used adopt organo silane coupling agent ceramic membrane is carried out to chemical modification, water droplet the contact angle on film surface be 90～170 degree; Passage internal diameter 6mm, cross-flow velocity 7 m/s, working pressure 0.6MPa, membrane permeation flux 0.8m
3m
-2h
-1.
4, infiltration evaporation dealcoholysis operation and decolouring press filtration operation
Material in relay tank 2 enters infiltration vaporization membrane module by pump delivery, and propyl carbinol is preferentially separated, and returns to esterifying kettle and continues recycle, and concentrated tributyl citrate is packaged to be finished product through decolouring, press filtration.The yield of tributyl citrate is 97.0%.Adopt polydimethylsiloxane (PDMS)/aluminum oxide infiltrating and vaporizing membrane, working pressure 0.2 MPa, membrane permeation flux 4kgm
-2h
-1.
embodiment 3
1, esterification step
Citric acid and propyl carbinol are dropped in reactor according to the mol ratio of 1:6, add 3%(to account for the mass percent of citric acid) heteropolyacid catalyst 100 nm, close dog-house, open chuck heating steam valve, control steam < 0.6 MPa(gauge pressure).Note water outlet situation, strict control still internal pressure (gauge pressure) < 0.015 MPa, in order to avoid cause punching material, the control of reaction top temperature is less than 140 DEG C, reaction reaches 4 hours, sample examination, then samples once per half an hour, when the acid number of thick ester liquid is less than 0.02mgKOH/g, can think that esterification finishes, close chuck heating steam valve, close reverse flow valve, stop stirring.Open reactor condenser cooling.
2, in embrane method and washing step
After completion of the reaction, the resultant of reaction material pump that is mixed with catalyzer is exported, after metering, material enters neutralization tank, with 4% KOH alkaline solution neutralization, then leaves standstill and makes ester water stratification, and water is in the bottom of neutralization tank, by putting into and water collecting tank after metering.Ester layer is exported by pump, and adds continuously washing simultaneously, enters together hydrophilic porous ceramic film component, carries out aqueous phase separation, is washed till neutrality.The concentrated material of holding back side mainly comprises propyl carbinol, tributyl citrate and catalyzer, enters relay tank 1 and regulates pressure, and per-meate side is isolated water to wastewater collection tank.Adopting aperture is the ceramic-metal composite film of 0.5 μ m, 19 passages, passage internal diameter 4mm, cross-flow velocity 3m/s, working pressure 0.5MPa, membrane permeation flux 0.5m
3m
-2h
-1.
3, embrane method catalyst separating operation
Material in relay tank 1 enters close Organic Compound porous ceramics membrane module via pump, and wherein propyl carbinol and tributyl citrate are separated and entered relay tank 2 through per-meate side.Catalyzer is trapped, and in the time being concentrated to solid content and reaching 15%, sepn process completes, and returns to esterifying kettle for lower secondary response.Adopt aperture be the ceramic membrane of 0.005 μ m, 7 passages, and the modification of ceramic membrane used adopt organo silane coupling agent ceramic membrane is carried out to chemical modification, water droplet the contact angle on film surface be 90～170 degree; Passage internal diameter 6mm, cross-flow velocity 2 m/s, working pressure 0.1MPa, membrane permeation flux 0.02 m
3m
-2h
-1.
4, infiltration evaporation dealcoholysis operation and decolouring press filtration operation
Material in relay tank 2 enters infiltration vaporization membrane module by pump delivery, and propyl carbinol is preferentially separated, and returns to esterifying kettle and continues recycle, and concentrated tributyl citrate is packaged to be finished product through decolouring, press filtration.The yield of tributyl citrate is 96.8%.Adopt polydimethylsiloxane (PDMS)/aluminum oxide infiltrating and vaporizing membrane, working pressure 0.2 MPa, membrane permeation flux 4kgm
-2h
-1.
Claims (4)
1. a continuous production technology for tributyl citrate, is characterized in that comprising step:
(1) esterification of citric acid and butanols: citric acid, propyl carbinol and solid catalyst are added in reactor, carry out esterification under conventional reaction process condition;
(2) in embrane method and washing: after esterification finishes, add in alkaline solution and after, leave standstill and make ester water stratification, getting upper strata ester layer adds water continuously and enters together hydrophilic porous membrane module, carry out aqueous phase separation, until ester layer is washed till to neutrality, obtain holding back the concentrated material of side, mainly comprise propyl carbinol, tributyl citrate and catalyzer; Per-meate side separates water outlet to wastewater treatment;
(3) embrane method catalyst separating: the concentrated material of holding back side enters lipophilicity porous-membrane module and carries out solid-liquid separation, and wherein propyl carbinol and tributyl citrate are separated through per-meate side, the solid catalyst of holding back reclaims;
(4) infiltration evaporation dealcoholysis: the mixture of propyl carbinol and tributyl citrate is delivered into infiltration vaporization membrane module, and propyl carbinol is isolated and reclaimed from per-meate side, obtains concentrated tributyl citrate;
(5) decolouring press filtration obtains tributyl citrate;
Wherein, described solid catalyst is solid acid;
In step (2), described hydrophilic porous membrane module is tubular type mineral membrane, and it is symmetry or the asymmetric membrane of pottery, metal or its matrix material formation of 5～500 nm that described mineral membrane adopts mean pore size;
The membrane sepn operating parameters of step (2) is: cross-flow velocity 1～5 m/s, working pressure 0.1～0.5 MPa;
In step (3), described lipophilicity porous-membrane module is modified ceramic film; Ceramic membrane adopt mean pore size be 5～500 nm pottery form symmetry or asymmetric membrane, and the modification of ceramic membrane used adopt organo silane coupling agent ceramic membrane is carried out to chemical modification, water droplet the contact angle on film surface be 90～170 degree;
The membrane sepn operating parameters of step (3) is: cross-flow velocity 1～7m/s, working pressure 0.1～0.6 MPa;
In step (4), the supporting layer of described infiltrating and vaporizing membrane is aluminum oxide, and separating layer is polydimethylsiloxane.
2. the continuous production technology of tributyl citrate according to claim 1, is characterized in that: described solid acid is molecular sieve catalyst, super acidic catalyst or heteropolyacid catalyst; The particle diameter of catalyzer is 10～100 nm.
3. the continuous production technology of tributyl citrate according to claim 1, is characterized in that: in step (1), the mol ratio of citric acid and propyl carbinol is 1:4～1:6; It is 1%～3% that described solid catalyst accounts for citric acid mass percent; Described enzymatic synthesis condition is: at 100～140 DEG C, react 2～4 hours.
4. the continuous production technology of tributyl citrate according to claim 1, is characterized in that: in step (2), described alkaline solution is that concentration is 3%～5% sodium carbonate, sodium hydroxide or potassium hydroxide solution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110138013.1A CN102249916B (en) | 2011-05-26 | 2011-05-26 | Continuous production process for tributyl citrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110138013.1A CN102249916B (en) | 2011-05-26 | 2011-05-26 | Continuous production process for tributyl citrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102249916A CN102249916A (en) | 2011-11-23 |
| CN102249916B true CN102249916B (en) | 2014-07-23 |
Family
ID=44977531
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110138013.1A Active CN102249916B (en) | 2011-05-26 | 2011-05-26 | Continuous production process for tributyl citrate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102249916B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102649748B (en) * | 2012-04-11 | 2014-04-23 | 江苏雷蒙化工科技有限公司 | Neutralization and water washing continuation device of citrate |
| CN102701975A (en) * | 2012-04-11 | 2012-10-03 | 江苏雷蒙化工科技有限公司 | Improvement of process for synthesizing acetyl tri-n-butyl citrate by activated carbon supported sulfuric acid |
| CN103553903B (en) * | 2013-11-01 | 2015-05-06 | 桂林甙元生物科技有限公司 | Novel process for extracting not smaller than 98% of natural ferulic acid from rice bran oil processing leftovers |
| CN106543000A (en) * | 2016-10-27 | 2017-03-29 | 南京科技职业学院 | A kind of esterification purifying and cleaning production technology |
| CN108452553B (en) * | 2018-04-01 | 2023-12-15 | 重庆梁彬新材料技术有限公司 | Alcohol water recovery unit for aerogel |
| CN109776314B (en) * | 2019-01-31 | 2021-11-12 | 新昌县泰如科技有限公司 | Preparation method of cinnamate |
| CN112679354A (en) * | 2020-12-31 | 2021-04-20 | 浙江物美生物科技有限公司 | Production process of isopropyl myristate |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101125814A (en) * | 2007-09-17 | 2008-02-20 | 李祥庆 | Method for synthesizing acetyl tributyl citrate by using ion type catalyst |
| CN101181689A (en) * | 2007-09-13 | 2008-05-21 | 西北师范大学 | Heteropolyacid catalyst using paligorskite as carrier as well as preparation and uses thereof |
| CN101255114A (en) * | 2007-09-06 | 2008-09-03 | 兰州理工大学 | Method for preparing oleoyl tributyl citrate plasticizer |
-
2011
- 2011-05-26 CN CN201110138013.1A patent/CN102249916B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101255114A (en) * | 2007-09-06 | 2008-09-03 | 兰州理工大学 | Method for preparing oleoyl tributyl citrate plasticizer |
| CN101181689A (en) * | 2007-09-13 | 2008-05-21 | 西北师范大学 | Heteropolyacid catalyst using paligorskite as carrier as well as preparation and uses thereof |
| CN101125814A (en) * | 2007-09-17 | 2008-02-20 | 李祥庆 | Method for synthesizing acetyl tributyl citrate by using ion type catalyst |
Non-Patent Citations (2)
| Title |
|---|
| 固体酸催化合成无毒增塑剂柠檬酸三正丁酯;李秀瑜;《精细化工》;19991231;第16卷;第42页第1.2小节，摘要 * |
| 李秀瑜.固体酸催化合成无毒增塑剂柠檬酸三正丁酯.《精细化工》.1999,第16卷第42页第1.2小节，摘要. |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102249916A (en) | 2011-11-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102249916B (en) | Continuous production process for tributyl citrate | |
| CN102703535B (en) | New technology for producing acrylamide by using ceramic membrane bioreactor | |
| CN102795964B (en) | 20000-ton-annual-yield production technique of trimethylolpropane by calcium method | |
| CN101671324B (en) | Production method of glucolactone | |
| CN102382203B (en) | High-efficiency extraction process for polysaccharide of lotus seeds | |
| CN102795963A (en) | Process for preparing trimethylolpropane by adopting centrifugal filtering calcium method | |
| CN101838198A (en) | Method for preparing carboxylic ester | |
| CN102068945A (en) | Reactive distillation device and method for separating and purifying methylal | |
| CN102796011A (en) | Preparation method for p-aminodiphenylamine | |
| CN102161008B (en) | Method for recovering catalyst in preparation of cyclohexene by partial hydrogenation of benzene | |
| CN204039299U (en) | A kind of purifying plant of high-purity sodium formate | |
| CN101560239B (en) | Production process for extracting saponins from yellow ginger by using solvent catalyzing method | |
| CN204058303U (en) | A kind of purifying plant of sodium formiate | |
| CN104130096B (en) | A kind of method being continuously separated high-purity longifolene from heavy turpentine | |
| CN102659572B (en) | Preparation method of dehydroabietic acid | |
| CN204162410U (en) | The harmless treatment unit of waste silicon powder | |
| CN107201685A (en) | The pilot production line and its technique of Cellulose nanocrystal are extracted from biomass resource | |
| CN102617309A (en) | Process for preparing acetaldehyde | |
| CN106543000A (en) | A kind of esterification purifying and cleaning production technology | |
| CN210030513U (en) | Extraction and dehydration system in trioxymethylene production process | |
| CN105399874B (en) | A kind of polyvinyl butyral resin synthetic method based on homogeneous and heterogeneous two-stage reaction | |
| CN110026233A (en) | A kind of method that ardealite extraction aluminium modified composite catalyst prepares propylene | |
| CN204079854U (en) | A kind of green serialization can prepare the system of high-purity thermoplastic phenolic resin | |
| CN204147853U (en) | A kind of reaction dewater unit | |
| CN219567596U (en) | Alumina red mud recycling equipment |
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 | ||
| C56 | Change in the name or address of the patentee | ||
| CP02 | Change in the address of a patent holder |
Address after: 225700 Zhaoyang Industrial Park, Xinghua, Jiangsu, Taizhou Patentee after: Nanjing College of Chemical Technology Address before: 210048 Jiangsu Province, Nanjing city Liuhe District Dachang geguan Road No. 625 Patentee before: Nanjing College of Chemical Technology |