CN104262189A - Method for liquid-phase preparation of high-purity N, N-diethylformamide - Google Patents
Method for liquid-phase preparation of high-purity N, N-diethylformamide Download PDFInfo
- Publication number
- CN104262189A CN104262189A CN201410532113.6A CN201410532113A CN104262189A CN 104262189 A CN104262189 A CN 104262189A CN 201410532113 A CN201410532113 A CN 201410532113A CN 104262189 A CN104262189 A CN 104262189A
- Authority
- CN
- China
- Prior art keywords
- diethylformamide
- methyl
- diethylamine
- formiate
- reaction
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to the technical field of organic synthesis, in particular to a method for liquid-phase preparation of N, N-diethylformamide. The method comprises the following steps: reacting methyl formate, diethylamine and a catalyst at a certain temperature under a certain pressure in a reaction still, removing the methyl formate, methanol and the diethylamine from a liquid-phase mixture reaction product through coarse distillation, carrying out fine distillation under reduced pressure in a fine distillation tower, and obtaining the N, N-diethylformamide with a purity higher than 99.9% through fine distillation. A high-purity N, N-diethylformamide product with low iron ion content can be obtained by the method, and zero pollution is realized in the production process. The method has excellent industrial application prospects in electronic washing and liquid crystal panel manufacture industries.
Description
Technical field
The present invention relates to organic synthesis technology field, particularly a kind of liquid phase prepares N, the method for N-diethylformamide.
Background technology
N, N-diethylformamide is a kind of colourless transparent liquid, has low toxicity, can dissolve multiple mineral compound, can be miscible with water, alcohol, ether, ester and aromatics.
Methyl-formiate and diethylamine produce N, the processing method of N-diethylformamide, and chemical equation is as follows:
CHOOCH
3 + NH(CH
3CH
2)
2→ CHON(CH
3CH
2)
2 + CH
3OH
Using at present compared with multi-catalyst in the method for preparation N, N-diethylformamide is hydrofining and clay-filtered, and these two kinds of catalyzer exist when starting material damage comparatively large, and the feature of easy inactivation.
Summary of the invention
A kind of methyl-formiate and diethylamine liquid phase reaction is the object of the present invention is to provide to obtain high purity N, the new process of N-diethylformamide, make it to overcome problem higher because of iron ion content in product, this product is more widely used at liquid crystal panel production field, the method production process environmental protection simultaneously, starting material utilize high.
In order to realize foregoing invention object, the present invention adopts following technical proposals:
A kind of liquid phase prepares N, and the method for N-diethylformamide, comprises the following steps:
A) join in reactor by a certain amount of methyl-formiate, diethylamine and catalyzer, the water content of wherein said methyl-formiate is less than or equal to 0.5%, and diethylamine purity is more than or equal to 99.5%, and the mol ratio of methyl-formiate and diethylamine is 1:0.6-2:1;
B) reacted liquid phase mixture carries out rectification under vacuum after slightly heating up in a steamer and removing methyl-formiate, diethylamine, methyl alcohol in rectifying tower, then rectifying obtains the N that purity is greater than 99.9%, N-diethylformamide, returns reactor recycle through slightly heating up in a steamer the excessive methyl-formiate, the diethylamine that remove;
C) catalyzer removes moisture Reusability through drying after using.
In the method for above-mentioned preparation N, N-diethylformamide, in step a), methyl-formiate is excessive relative to another reactant diethylamine; Raw material methyl-formiate water content refers to the mass percent in moisture methyl-formiate shared by moisture; The purity of diethylamine refers to the mass percent shared by pure dimethylamine.
Methyl-formiate and diethylamine liquid phase reaction obtain N, and N-diethylformamide processing method, mainly comprises the following steps realization:
(1) proportionally join in reactor by a certain amount of methyl-formiate, diethylamine and catalyzer, react and to carry out in autoclave, reactor is furnished with the off-set facility such as conventional agitator and heating unit; Adopt the mixture of any one or two kinds in type ZSM 5 molecular sieve and gama-alumina as catalysts, the mass ratio of the catalyzer that first time adds and methyl-formiate is 0.01:1-0.5:1;
(2) after in step (1), reaction mass and catalyzer add, then reactor starts heating, adopt methyl-formiate excessive 10%-20%(mol ratio), system boosts voluntarily or makes to reach in reactor to need pressure condition by the mode of nitrogen pressurization, synthesis reaction temperature is 60-180 DEG C, and building-up reactions pressure is 0.1 MPa-1.0MPa;
(3) the reaction solution material after having reacted in step (2) slightly heats up in a steamer in rectifying tower, and adopt glass spring filler, overhead extraction mouth under overhead condenser, tower is provided with side take-off mouth, tower reactor electricity consumption heating mantle heats, charging in tower, operate continuously; First slightly heat up in a steamer, the methyl-formiate that overhead extraction is excessive and the diethylamine do not reacted completely on a small quantity, extraction methyl alcohol in tower; Again through vacuumizing rectification under vacuum, a small amount of first alcohol and water of overhead extraction, tower reactor obtains the higher N of purity, the thick product of N-diethylformamide;
(4) N obtained in step (3), the thick product of N-diethylformamide is through rectification under vacuum, and overhead extraction obtains the high purity N of 99.9%, N-diethylformamide product.
Positively effect of the present invention is embodied in:
(1) this device adopts the method time for adding quantitatively dripped to be 1-2 hour, because adopting in this device
Catalyzer substantially increase speed of response, therefore substantially reduce time for adding; This device reaction adopts catalyzer to substantially increase N, the activity and selectivity of N diethylformamide building-up reactions, and substantially reduces the reaction times and improve product purity more than 95%;
(2) reaction of N, N diethylformamide is thermopositive reaction, takes intensification 100-120 DEG C in the application
The mode of pressurization 0.1-1.0 MPa, improves the speed of reaction, substantially increases output and the economy of product, and greatly saved energy consumption for follow-up atmospheric distillation.
(3) topping still adopts segmentation extraction overhead product, and overhead extraction methyl-formiate water content≤0.5% can
Direct recycling, and methyl alcohol utilizes as our company's other products starting material.Save production cost, save raw materials cost.
(4) overcome problem higher because of iron ion content in product, make this product raw at liquid crystal panel
Product field is more widely used, and the method production process environmental protection simultaneously, starting material utilize high.
Embodiment
Below in conjunction with embodiment, the present invention is described in further detail.But this should be interpreted as that the scope of the above-mentioned theme of the present invention is only limitted to following embodiment, all technology realized based on content of the present invention all belong to scope of the present invention.
In following examples, reaction is all carried out in autoclave, and reactor has stirring and electric heater unit.First add quantitative raw material methyl-formiate, diethylamine and catalyzer post-heating to heat up, reach timing sampling after reaction conditions, with the change of gas chromatographic detection reactant.
Embodiment 1:
Reaction adds materials as primary catalyst (type ZSM 5 molecular sieve) 51.8g, methyl-formiate 103.71g(water content≤0.5%), diethylamine 82.1g(purity >=99.5%), reactor natural pressure 1.2MPa, temperature of reaction 110 DEG C, pressure rises to 0.45MPa, stirring reaction 4 hours, transformation efficiency >=98% of diethylamine, selectivity >=95.8% of N, N-diethylformamide.
In reaction product, diethylamine is 0.88%, methyl alcohol is 18.17%, methyl-formiate is 20.26%, N, N-diethylformamide is 57.37%, other impurity 3.32%(weight percent) material slightly heat up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing 2400mm in rectifying tower, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First take out normal pressure slightly to heat up in a steamer, overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085Mpa, the a small amount of methyl alcohol of overhead extraction, the N of 20% is discharged continuously at the bottom of rectifying tower reactor, N-diethylformamide mixed solution, enters reactor and proceeds reaction, obtain N in tower after pump boosting, N-diethylformamide purity is greater than 99.9%, the recovery per pass 93.9% of product.Embodiment 2:
Reaction adds materials as primary catalyst (type ZSM 5 molecular sieve) 104g, methyl-formiate 103.71g(water content≤0.5%), diethylamine 82.1g(purity >=99.5%), reactor natural pressure 1.2MPa, temperature of reaction 110 DEG C, pressure rises to 0.45MPa, stirring reaction 4 hours, transformation efficiency >=93% of diethylamine, selectivity >=95% of N, N-diethylformamide.
Reaction product is containing diethylamine 3.09%, methyl alcohol 17.1%, methyl-formiate 22.08%, N, N-diethylformamide 53.98%, other 3.75%(weight percent) material slightly heat up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing 2400mm in rectifying tower, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First take out normal pressure slightly to heat up in a steamer, overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085Mpa, the a small amount of methyl alcohol of overhead extraction, the N of 20% is discharged continuously at the bottom of rectifying tower reactor, N-diethylformamide mixed solution, enters reactor and proceeds reaction, obtain N in tower after pump boosting, N-diethylformamide purity is greater than 99.9%, the recovery per pass 88.4% of product.
Embodiment 3:
Reaction adds materials as primary catalyst (type ZSM 5 molecular sieve) 51.8g, methyl-formiate 103.71g(water content≤0.5%), diethylamine 82.1g(purity >=99.5%), reactor natural pressure 1.2MPa, temperature of reaction 120 DEG C, pressure rises to 0.45MPa, stirring reaction 4 hours, transformation efficiency >=98.2% of diethylamine, selectivity >=96% of N, N-diethylformamide.
Reaction product is containing diethylamine 0.8%, methyl alcohol 18.25%, methyl-formiate 20.19%, N, N-diethylformamide 57.6%, other 3.16%(weight percent) material slightly heat up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing 2400mm in rectifying tower, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First take out normal pressure slightly to heat up in a steamer, overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085Mpa, the a small amount of methyl alcohol of overhead extraction, the N of 20% is discharged continuously at the bottom of rectifying tower reactor, N-diethylformamide mixed solution, enters reactor and proceeds reaction, obtain N in tower after pump boosting, N-diethylformamide purity is greater than 99.9%, the recovery per pass 94.3% of product.
Embodiment 4:
Reaction adds materials as primary catalyst (type ZSM 5 molecular sieve) 51.8g, methyl-formiate 103.71g(water content≤0.5%), diethylamine 82.1g(purity >=99.5%), reactor natural pressure 1.2MPa, temperature of reaction 160 DEG C, pressure rises to 0.45MPa, stirring reaction 4 hours, transformation efficiency >=97.8% of diethylamine, selectivity >=97% of N, N-diethylformamide.
Reaction product is containing diethylamine 0.97%, methyl alcohol 18.36%, methyl-formiate 20.33%, N, N-diethylformamide 57.97%, other 2.37%(weight percent) material slightly heat up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing 2400mm in rectifying tower, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First take out normal pressure slightly to heat up in a steamer, overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085Mpa, the a small amount of methyl alcohol of overhead extraction, the N of 20% is discharged continuously at the bottom of rectifying tower reactor, N-diethylformamide mixed solution, enters reactor and proceeds reaction, obtain N in tower after pump boosting, N-diethylformamide purity is greater than 99.9%, the recovery per pass 94.9% of product.
Embodiment 5:
Reaction adds materials as primary catalyst (type ZSM 5 molecular sieve) 160g, methyl-formiate 336g(water content≤0.5%), diethylamine 266g(purity >=99.5%), temperature of reaction 120 DEG C, reaction is natural pressure 1.2MPa, stirring reaction 3.5 hours, transformation efficiency >=98% of quadrol, selectivity >=96.80% of N, N-diethylformamide.
Reaction product contains diethylamine 0.88% containing reaction product, methyl alcohol 18.36%, methyl-formiate 20.26%, N, N-diethylformamide 57.97%, other 2.53%(weight percent) material slightly heat up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing height 2400mm in rectifying tower, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First take out normal pressure slightly to heat up in a steamer, overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085Mpa, the a small amount of methyl alcohol of overhead extraction, the N of 20% is discharged continuously at the bottom of rectifying tower reactor, N-diethylformamide mixed solution, enters reactor and proceeds reaction, obtain N in tower after pump boosting, N-diethylformamide purity is greater than 99.9%, the recovery per pass 94.9% of product.Embodiment 6:
Reaction adds materials as primary catalyst (type ZSM 5 molecular sieve) 400g, methyl-formiate 800g(water content≤0.5%), dimethylamine 633.4g(purity >=99.5%), temperature of reaction 160 DEG C, reaction is natural pressure 1.2MPa, stirring reaction 4 hours, the transformation efficiency 98% of diethylamine, selectivity >=98% of N, N-diethylformamide.
Reaction product is containing diethylamine 0.88%, methyl alcohol 18.59%, methyl-formiate 20.26%, N, N-diethylformamide 58.69%, the material of other 1.58% (weight percent) slightly heats up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing 2400mm in rectifying tower, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First normal pressure slightly heats up in a steamer, and overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085MPa, the a small amount of methyl alcohol of overhead extraction, the N of 20% is discharged continuously at the bottom of rectifying tower reactor, N-diethylformamide mixed solution, enters reactor and proceeds reaction, obtain N in tower after pump boosting, N-diethylformamide purity is greater than 99.9%, the recovery per pass 96.1% of product.
Embodiment 7:
Reaction adds materials as methyl-formiate 103.71g(water content≤0.5%), diethylamine 82.1g(purity >=99.5%), reactor natural pressure 1.2MPa, temperature of reaction 110 DEG C, pressure rises to 0.45MPa, stirring reaction 4 hours, transformation efficiency >=91% of diethylamine, selectivity >=85.7% of N, N-diethylformamide.
Reaction product is containing diethylamine 3.98%, methyl alcohol 15.95%, methyl-formiate 22.80%, N, N-diethylformamide 47.65%, other 9.62%(weight percent) material slightly heat up in a steamer respectively and distillation operation in the rectifying tower of the identical Φ 400mm of two structures, metal mesh opening 500 ripple packing in rectifying tower, packed height 2400mm, overhead extraction mouth under overhead condenser, on tower, 500mm place is provided with side take-off mouth, 500mm place charging under tower, operate continuously.First take out normal pressure slightly to heat up in a steamer, overhead extraction diethylamine and methyl-formiate, extraction methyl alcohol in tower, methyl-formiate and diethylamine are back in reactor and proceed to react.Crude distillation column liquid enters rectifying tower and carries out rectification under vacuum, gauge pressure is-0.085Mpa, a small amount of methyl alcohol of overhead extraction, discharges the N of 20% at the bottom of rectifying tower reactor continuously, N-diethylformamide mixed solution, after pump boosting, enter reactor proceed reaction, obtain N in tower, N-diethylformamide purity is greater than 99.5%, iron ion content is greater than 0.0004(in Fe w%), product colourity is greater than 20, places more than 30 days product colours and easily turns yellow, and is not easy to store.The recovery per pass 78% of product.
Claims (7)
1. liquid phase prepares a high purity N, the method for N-diethylformamide, it is characterized in that the method comprises the following steps:
A) join in reactor by a certain amount of methyl-formiate, diethylamine and catalyzer, the mol ratio of methyl-formiate and diethylamine is 1:0.6-2:1; The water content of wherein said methyl-formiate is less than or equal to 0.5%, and diethylamine purity is more than or equal to 99.5%,
B) by liquid phase mixture reacted in step a) through slightly heating up in a steamer step, in rectifying tower, rectification under vacuum is carried out after methyl-formiate to be removed, diethylamine, methyl alcohol, then rectifying obtains the N that purity is greater than 99.9%, N-diethylformamide, returns reactor recycle through slightly heating up in a steamer the excessive methyl-formiate, the diethylamine that remove;
C) catalyzer removes moisture Reusability through drying after using.
2. liquid phase according to claim 1 prepares high purity N, and the method for N-diethylformamide, is characterized in that: the catalyzer described in step a) is the mixture of any one or two kinds in type ZSM 5 molecular sieve and gama-alumina.
3. liquid phase according to claim 1 prepares high purity N, and the method for N-diethylformamide, is characterized in that: the mass ratio 0.01:1-0.5:1 of the catalyzer used in step a) and methyl-formiate.
4. the liquid phase according to claim arbitrary in claim 1-3 prepares N, and the method for N-diethylformamide, is characterized in that: the temperature of reaction in described step a) is 60 DEG C-180 DEG C, and reaction pressure is 0.1 MPa-1.0MPa.
5. liquid phase according to claim 1 prepares N, and the method for N-diethylformamide, is characterized in that: in described step a), the mol ratio of methyl-formiate and diethylamine is 1:0.6-1:0.9.
6. liquid phase according to claim 4 prepares N, and the method for N-diethylformamide, is characterized in that: the temperature of reaction in described step a) is 100 DEG C-120 DEG C.
7. liquid phase according to claim 4 prepares N, and the method for N-diethylformamide, is characterized in that: the reaction pressure in described step a) is 0.2 MPa-0.5MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410532113.6A CN104262189A (en) | 2014-10-11 | 2014-10-11 | Method for liquid-phase preparation of high-purity N, N-diethylformamide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410532113.6A CN104262189A (en) | 2014-10-11 | 2014-10-11 | Method for liquid-phase preparation of high-purity N, N-diethylformamide |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104262189A true CN104262189A (en) | 2015-01-07 |
Family
ID=52153809
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410532113.6A Pending CN104262189A (en) | 2014-10-11 | 2014-10-11 | Method for liquid-phase preparation of high-purity N, N-diethylformamide |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104262189A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110156621A (en) * | 2019-05-08 | 2019-08-23 | 重庆建峰工业集团有限公司 | The method of liquid-liquid Homogeneous synthesis DMAC N,N' dimethyl acetamide is carried out in micro passage reaction |
| CN111253277A (en) * | 2020-03-31 | 2020-06-09 | 迈奇化学股份有限公司 | Production method of N, N-diethyl acetamide |
| CN111253274A (en) * | 2020-02-13 | 2020-06-09 | 南京工业大学 | Preparation method of dialkyl formamide |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103012183A (en) * | 2012-12-18 | 2013-04-03 | 王传良 | Preparation method of N,-N-diethyl-formamide |
| CN103922957A (en) * | 2014-03-21 | 2014-07-16 | 迈奇化学股份有限公司 | Preparation method of continuous production of diethylformamide |
-
2014
- 2014-10-11 CN CN201410532113.6A patent/CN104262189A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103012183A (en) * | 2012-12-18 | 2013-04-03 | 王传良 | Preparation method of N,-N-diethyl-formamide |
| CN103922957A (en) * | 2014-03-21 | 2014-07-16 | 迈奇化学股份有限公司 | Preparation method of continuous production of diethylformamide |
Non-Patent Citations (1)
| Title |
|---|
| 刘兴泉: "二乙胺液相催化羰化制备二乙基甲酰胺", 《应用化学》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110156621A (en) * | 2019-05-08 | 2019-08-23 | 重庆建峰工业集团有限公司 | The method of liquid-liquid Homogeneous synthesis DMAC N,N' dimethyl acetamide is carried out in micro passage reaction |
| CN111253274A (en) * | 2020-02-13 | 2020-06-09 | 南京工业大学 | Preparation method of dialkyl formamide |
| CN111253277A (en) * | 2020-03-31 | 2020-06-09 | 迈奇化学股份有限公司 | Production method of N, N-diethyl acetamide |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103641721B (en) | Energy-saving process for producing and separating dimethyl carbonate | |
| TWI579266B (en) | Method for preparing glycol ester using reactive distillation | |
| CN103282338A (en) | Method for producing formic acid by reacting carbon dioxide with hydrogen | |
| CN104761429A (en) | Dimethyl carbonate and ethylene glycol production process | |
| CN110562924A (en) | Preparation method of electronic grade hydrogen bromide | |
| CN104529763A (en) | Process and device for synthesizing ethyl formate with reactive distillation dividing wall column | |
| CN104387236B (en) | A kind of propilolic alcohol, 1,4-butynediols and methenamine three coproduction continuous producing method | |
| CN104262189A (en) | Method for liquid-phase preparation of high-purity N, N-diethylformamide | |
| CN102134191B (en) | Process method for producing ethyl acetate by catalytic rectification | |
| CN103724279A (en) | Portable synthesis method for preparing 2-methyl-4-amino-5-aminoethylpyrimidine through one-step cyclization reaction | |
| CN102807500B (en) | Method for liquid-phase preparation of N, N-dimethylacetamide | |
| CN108947943B (en) | Method for direct catalysis of dimerization of 5-methylfurfuryl alcohol by solid phosphotungstic acid | |
| CN102304055B (en) | Method for preparing ethanolamine hydrochlorides and coproduct ethanolamine | |
| CN104829559A (en) | Method of preparing Nu-valerolactone from methyl levulinate | |
| CN104262081B (en) | A kind ofly full chloro-1,3-butadiene gas phase is utilized to prepare the method for perchloro-ethane | |
| CN104710402B (en) | Dicyclohexyl crown ether synthesis method | |
| CN108947774A (en) | A kind of method and device of separating isopropanol | |
| CN104098072B (en) | A kind of gas phase catalytic synthesis dichloride sulphur preparing process | |
| CN103739442B (en) | A kind of preparation method of 3-methyl-3-butene-1-alcohol | |
| CN104447391A (en) | Methylenebisamide derivative and preparation method thereof | |
| CN110862296B (en) | Method for separating reaction product in chloromethane production process | |
| CN102351838B (en) | Synthetic method of 1,4-dioxane-2,5-diol | |
| CN102603490B (en) | Synthesis method of high-purity p-tert-butylcatechol | |
| CN103724210A (en) | Production method of N-ethyl-n-butylamine | |
| CN103012204A (en) | Preparation method of cyanobenzene |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20150107 |
|
| RJ01 | Rejection of invention patent application after publication |