CN106554274B - The technique of catalytic distillation Synthesis of Isopropyl Salicylate - Google Patents
The technique of catalytic distillation Synthesis of Isopropyl Salicylate Download PDFInfo
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- CN106554274B CN106554274B CN201510641518.8A CN201510641518A CN106554274B CN 106554274 B CN106554274 B CN 106554274B CN 201510641518 A CN201510641518 A CN 201510641518A CN 106554274 B CN106554274 B CN 106554274B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/04—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides onto unsaturated carbon-to-carbon bonds
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- 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
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- 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
- Y02P20/10—Process efficiency
Abstract
The present invention relates to a kind of techniques of catalytic distillation Synthesis of Isopropyl Salicylate.The salicylic acid and propylene being dissolved in isopropyl ether carry out esterification in fixed bed reactors together, after reaching reaction balance, esterification reaction product enters the conversion zone top of catalytic distillation tower, propylene enters in catalytic distillation tower from the lower part of conversion zone, esterification gradient reaction is carried out in the conversion zone of catalytic distillation tower, the isopropyl salicylate for reacting generation is discharged from tower reactor.The present invention adds catalytic distillation technology using pre-reaction, salicylic conversion ratio can be increased substantially, salicylic conversion ratio >=99.5% of the present invention, and reaction selectivity (gaultherolin >=99.5%) greatly improved, and plant investment is saved, while reducing separation costs and energy consumption.The present invention does not have to alcohols and the concentrated sulfuric acid during the reaction, solves reaction process water, sulfuric acid brings corrosion and pollution problem, is environmentally protective process route.
Description
Technical field
The invention belongs to chemical fields, and in particular to a kind of technique of catalytic distillation Synthesis of Isopropyl Salicylate.
Background technique
Isopropyl salicylate is also known as septichen isopropyl ester, belongs to aromatic series esters, and isopropyl salicylate is a kind of
Important industrial chemicals and intermediate can be used as solvent, catalyst, plastic additive and synthesis medicine, pesticide etc..China bigcatkin willow
Isopropyl propionate is mainly used as the intermediate of pesticide isocarbophos, Isofenphos methyl, it is also possible to make the centre of fragrance and organic synthesis
Body etc..The industry of the different ester of salicylic acid is combined to use salicylic acid isopropanol direct esterification mostly, also there is a small number of alcohol transesterifications
Method (such as benzyl salicylate, phenylethyl salicylate, salicylate cyclohexyl ester).
Currently, salicylic acid isopropanol direct esterification, which prepares isopropyl salicylate, generallys use sulfuric acid, thionyl chloride and five yuan
Nitration mixture etc. makees catalyst, although they can be such that esterification goes on smoothly, and cheap, big, side reaction that there are dosages
A series of problems, such as more, complex process, corrosion equipment and waste acid water exhaust emission environment.Therefore, domestic and international salicylic acid isopropanol
Reaction exploring more preferably esterification catalyst always.As once select mixed acid, sulphonic acids (such as chlorosulfonic acid, p-methyl benzenesulfonic acid),
Lewis acid (such as iron chloride, boric acid), sodium bisulfate, ferric potassium alum and dehydrating agent DCC.In recent years, a kind of novel esterification is anti-
Answer catalyst-solid acid catalyst that domestic and international researcher extensive concern, including molecular sieve type catalyst, solid super-strong acid is caused to be urged
Agent (such as SO42-/ TiO2 etc.), composite solid super acidic catalyst (such as SO42-/ TiO2-ZrO2 etc.) and solid heteropoly acid type
Catalyst.Compared with sulfuric acid catalyst, solid acid catalyst, which has, not to be corroded equipment, is easily isolated, recycles or regenerates, without useless
The advantages that acid discharge；But the reaction of solid acid only rests on the experimental stage of still reaction, does not carry out industrialized production.
CN1069892C describes a kind of using salicylic acid and propylene as the method for Material synthesis isopropyl salicylate, it is anti-
Although not generating waste water during answering, the processing such as unreacted salicylic acid calcium oxide can produce waste residue etc., sulfuric acid is catalyzed
The spent acid that agent generates does not say how to handle yet, and esterification occurs in tank reactor, it is possible to create the loss etc. of propylene
In conclusion in current technology, the overwhelming majority uses still reaction, and conversion ratio is low, and energy consumption is high, pollution compared with
Greatly.It is a kind of low in the pollution of the environment the purpose of the present invention is on the basis of existing technology, providing, reaction conversion ratio height, selecting response
Property it is good, process flow is simple, low energy consumption, extends equipment life, can operate continuously and environmentally protective preparation method.
Summary of the invention
In view of the deficiencies of the prior art, the object of the present invention is to provide a kind of works of catalytic distillation Synthesis of Isopropyl Salicylate
Skill can increase substantially salicylic conversion ratio, and reaction selectivity greatly improved, and save plant investment, simultaneously
Reduce energy consumption.
The technique of catalytic distillation Synthesis of Isopropyl Salicylate of the present invention, be dissolved in salicylic acid in isopropyl ether and
Propylene carries out esterification in fixed bed reactors together, and after reaching reaction balance, esterification reaction product enters catalytic distillation
The conversion zone top of tower, propylene enter in catalytic distillation tower from the lower part of conversion zone, carry out ester in the conversion zone of catalytic distillation tower
Change gradient reaction, the isopropyl salicylate for reacting generation is discharged from tower reactor.
Wherein:
The present invention is that a kind of fixed bed adds catalytic distillation solvent method esterification to generate the technique of isopropyl salicylate, wherein
Filling solid acid catalyst, molecular sieve or heteropoly acid in fixed bed reactors；Catalytic distillation tower uses bulk type catalytic distillation knot
Structure, catalytic distillation tower are divided into rectifying section, conversion zone and stripping section three parts, conversion zone filling solid acid catalyst, molecular sieve
Or heteropoly acid, stripping section and rectifying section are equipped with stainless steel helices, wherein solid acid catalyst is preferably highly acidic cation exchange
Resin catalyst.
In catalytic distillation tower unreacted propylene and isopropyl ether enter catalytic distillation column overhead and from tower top be discharged, into return
It returns catalytic distillation tower after stream tank reflux to be reacted, extra propylene and isopropyl ether return to fixed bed reactors and utilize.
Catalytic distillation tower conversion zone includes multiple catalyst beds, is equipped with gas phase channel in catalyst bed, and two adjacent urge
Plate is set between agent bed, the gaseous phase materials flowed up in tower bypass catalyst bed through gas phase channel, flow downward
Liquid phase material carry out the gradient reaction of salicylic acid esterification, air-liquid directly through catalyst bed and under the effect of the catalyst
Two phase materials carry out Mass and heat transfer on the plate of catalyst bed interlayer.
The present invention carries out most of reaction of salicylic acid esterification using fixed bed.Due to being handed in catalytic distillation tower conversion zone
Mistake carries out the separation of reaction with product, and reaction product constantly removes reaction zone, destroys balanced reaction, improves turning for reactant
Rate makes salicylic acid obtain deep conversion.
Compared with tank reactor, fixed bed adds the process flow of catalytic distillation process esterification generation isopropyl salicylate
Both reaction heat is taken full advantage of, energy consumption is reduced, and improves salicylic conversion ratio, reaches the mesh of salicylic acid deep conversion
, conversion ratio is greater than 99.5%.Fixed bed adds the technique one of catalytic distillation solvent method hydration reaction generation isopropyl salicylate
Aspect can increase substantially isopropyl salicylate reaction selectivity, and propylene and isopropyl ether are discharged from tower top completely, salicylic acid isopropyl
Ester is flowed out from tower reactor, and entire technical process does not need additional destilling tower and separated, thus simplifies process flow, reduces
Equipment investment expense.
Propylene and salicylic molar ratio are 1.0~3.0:1, isopropyl ether and salicylic molar ratio in fixed bed reactors
For 4~12:1.
The condition of fixed bed reactors are as follows: 90~170 DEG C of reaction temperature, 1.8~2.7MPa of reaction pressure, reaction velocity
0.1~2.0h-1。
The number of theoretical plate of catalytic distillation tower rectifying section is 12 pieces, the number of theoretical plate of conversion zone is 16 pieces, the theory of stripping section
Plate number is 5 pieces.
The condition of catalytic distillation tower are as follows: 1.6~2.5MPa of reaction pressure, conversion zone temperature are 80~150 DEG C, air speed 0.1
~1.0h-1, reflux ratio 0.2~2, propylene and salicylic molar ratio be 1.1~4.0:1, isopropyl ether and salicylic molar ratio
For 4~12:1.
In conclusion the invention has the following advantages that
(1) present invention adds catalytic distillation technology using pre-reaction, can increase substantially salicylic conversion ratio, the present invention
Salicylic conversion ratio >=99.5%, and reaction selectivity (gaultherolin >=99.5%) greatly improved, and save dress
Investment is set, while reducing separation costs and energy consumption.
(2) the present invention provides a kind of fixed bed add catalytic distillation process esterification generate isopropyl salicylate technique,
Main esterification is carried out with fixed bed, multiple gradient is re-started with the balance that catalytic distillation tower changes reaction product and reacts,
And specific process conditions are used, the selection of salicylic conversion ratio and reaction product bigcatkin willow isopropyl propionate is greatly improved
Property.
(3) isopropyl salicylate product in the prior art generally makees catalyst by sulfuric acid etc., with salicylic acid/isopropyl alcohol ester
Change method is made, since the addition reaction of alcohol has the generation of water；Sulphur acid as catalyst produces spent acid simultaneously, brings separation tired
It is difficult.And isopropyl salicylate made from salicylic acid/propylene method is used, still reaction is only rested on, conversion ratio is low, production cost
Height, process are complex.The preparation method of production isopropyl salicylate provided by the invention, is catalyzed using solid acid catalyst
Agent solves the deficiency of the above method using salicylic acid and propylene as raw material；The present invention was reacting unlike the prior art
Do not have to alcohols and the concentrated sulfuric acid in journey, solve the generation of reaction process water, sulfuric acid brings corrosion and pollution problem, utilizes fixed bed
Add catalytic distillation synthesis technology, it is environmentally protective process route that reaction conversion ratio and selectivity are high.
Detailed description of the invention
Fig. 1 is structure drawing of device used in the technique of catalytic distillation Synthesis of Isopropyl Salicylate of the present invention；
In figure: 1- propylene tank, the salicylic isopropyl ether solution reservoir of 2-, 3- fixed bed reactors, 4- supplement propylene storage
Tank, 5- rectifying section, 6- conversion zone, 7- stripping section, 8- tower reactor, 9- return tank.
Specific embodiment
Below with reference to embodiment, the present invention will be further described.
Embodiment 1
A kind of technique of catalytic distillation Synthesis of Isopropyl Salicylate, as shown in Figure 1, by being placed in bigcatkin willow acid dissolution isopropyl ether
In salicylic isopropyl ether solution reservoir 2, propylene is placed in propylene tank 1, the salicylic acid and propylene being dissolved in isopropyl ether
Esterification is carried out in fixed bed reactors 3 together, after reaching reaction balance, esterification reaction product enters catalytic distillation tower
6 top of conversion zone, the propylene supplemented in propylene tank 4 enters in catalytic distillation tower from the lower part of conversion zone 6, in catalytic distillation tower
Conversion zone 6 carry out esterification gradient reaction, react generation isopropyl salicylate flow into tower reactor 8 from tower reactor 8 be discharged, catalytic distillation
Unreacted propylene and isopropyl ether enter catalytic distillation column overhead and are discharged from tower top in tower, return again after flowing back into return tank 9
It is reacted to catalytic distillation tower, extra propylene and isopropyl ether return to fixed bed reactors and utilize.
Wherein: catalytic distillation tower is divided into 7 three parts of rectifying section 5, conversion zone 6 and stripping section, and conversion zone 6 loads highly acid
Cation exchange resin catalyst, stripping section 7 and rectifying section 5 are equipped with stainless steel helices, load highly acid in fixed bed reactors 3
Cation exchange resin catalyst.
Catalytic distillation tower conversion zone 6 includes multiple catalyst beds, is equipped with gas phase channel in catalyst bed, and two adjacent urge
Plate is set between agent bed, the gaseous phase materials flowed up in tower bypass catalyst bed through gas phase channel, flow downward
Liquid phase material carry out the gradient reaction of salicylic acid esterification, air-liquid directly through catalyst bed and under the effect of the catalyst
Two phase materials carry out Mass and heat transfer on the plate of catalyst bed interlayer.
The condition of fixed bed reactors 3: 110 DEG C of reaction temperature, reaction pressure 2.2MPa, reaction velocity 0.3h-1, propylene and
Salicylic acid molar ratio is 1.5:1, isopropyl ether and salicylic molar ratio are 6:1.
Catalytic distillation tower reaction condition: reaction pressure 2.0MPa, 6 temperature of conversion zone are 110 DEG C, air speed 0.2h-1, reflux ratio
0.5, propylene and salicylic acid molar ratio are 2.0:1, isopropyl ether and salicylic molar ratio are 6:1.
The technique provided using embodiment 1, salicylic conversion ratio 99.67%, the selectivity of isopropyl salicylate >=
99.56%.
Embodiment 2
A kind of technique of catalytic distillation Synthesis of Isopropyl Salicylate, processing step is same as Example 1, and unique difference exists
In:
The condition of fixed bed reactors 3: 110 DEG C of reaction temperature, reaction pressure 2.2MPa, reaction velocity 0.3h-1, propylene water
Poplar acid molar ratio 2.0:1, isopropyl ether and salicylic molar ratio are 8:1.
Catalytic distillation tower reaction condition: reaction pressure 2.0MPa, 6 temperature of conversion zone are 110 DEG C, air speed 1.0h-1, reflux ratio
0.5, propylene salicylic acid molar ratio 3.0:1, isopropyl ether and salicylic molar ratio are 8:1.
The technique provided using embodiment 1, salicylic conversion ratio 99.71%, the selectivity of isopropyl salicylate >=
99.63%.
Embodiment 3
A kind of technique of catalytic distillation Synthesis of Isopropyl Salicylate, processing step is same as Example 1, and unique difference exists
In:
Using molecular sieve as catalyst in fixed bed reactors 3 and catalytic distillation tower conversion zone 6；
The condition of fixed bed reactors 3: 150 DEG C of reaction temperature, reaction pressure 2.1MPa, reaction velocity 0.4h-1, propylene water
Poplar acid molar ratio 1.5:1, isopropyl ether and salicylic molar ratio are 6:1.
Catalytic distillation tower reaction condition: reaction pressure 2.0MPa, 6 temperature of conversion zone are 150 DEG C, air speed 0.2h-1, reflux ratio
1, propylene salicylic acid molar ratio 2.0:1, isopropyl ether and salicylic molar ratio are 6:1.
Salicylic conversion ratio 99.86%, selectivity >=99.58% of isopropyl salicylate.
Claims (8)
1. a kind of technique of catalytic distillation Synthesis of Isopropyl Salicylate, it is characterised in that: the salicylic acid being dissolved in isopropyl ether
Esterification is carried out in fixed bed reactors together with propylene, after reaching reaction balance, esterification reaction product enters catalysis and steams
The conversion zone top of tower is evaporated, propylene enters in catalytic distillation tower from the lower part of conversion zone, carries out in the conversion zone of catalytic distillation tower
It is esterified gradient reaction, the isopropyl salicylate for reacting generation is discharged from tower reactor；
Filling solid acid catalyst, molecular sieve or heteropoly acid in fixed bed reactors；
Catalytic distillation tower conversion zone includes multiple catalyst beds, is equipped with gas phase channel, two adjacent catalysts in catalyst bed
Plate is set between bed, the gaseous phase materials flowed up in tower bypass catalyst bed, the liquid to flow downward through gas phase channel
Phase materials carry out the gradient reaction of salicylic acid esterification, gas and liquid two phases directly through catalyst bed and under the effect of the catalyst
Material carries out Mass and heat transfer on the plate of catalyst bed interlayer.
2. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 1, it is characterised in that: catalytic distillation tower
It is divided into rectifying section, conversion zone and stripping section three parts, conversion zone filling solid acid catalyst, molecular sieve or heteropoly acid, stripping
Section and rectifying section are equipped with stainless steel helices.
3. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 1, it is characterised in that: solid acid catalysis
Agent is strong acid cation exchange resin catalyst.
4. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 1, it is characterised in that: catalytic distillation tower
In unreacted propylene and isopropyl ether enter catalytic distillation column overhead and be discharged from tower top, into return tank reflux after return and urge
Change destilling tower to be reacted, extra propylene and isopropyl ether return to fixed bed reactors and utilize.
5. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 1, it is characterised in that: fixed bed reaction
Propylene and salicylic molar ratio are 1.0~3.0:1 in device, and isopropyl ether and salicylic molar ratio are 4~12:1.
6. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 1, it is characterised in that: fixed bed reaction
The condition of device are as follows: 90~170 DEG C of reaction temperature, 1.8~2.7MPa of reaction pressure, 0.1~2.0h of reaction velocity-1。
7. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 2, it is characterised in that: catalytic distillation tower
The number of theoretical plate of rectifying section is 12 pieces, the number of theoretical plate of conversion zone is 16 pieces, and the number of theoretical plate of stripping section is 5 pieces.
8. the technique of catalytic distillation Synthesis of Isopropyl Salicylate according to claim 1, it is characterised in that: catalytic distillation tower
Condition are as follows: 1.6~2.5MPa of reaction pressure, conversion zone temperature be 80~150 DEG C, 0.1~1.0h of air speed-1, reflux ratio 0.2~
2, propylene and salicylic molar ratio are 1.1~4.0:1, and isopropyl ether and salicylic molar ratio are 4~12:1.
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| CN114213243A (en) * | 2021-12-03 | 2022-03-22 | 王义成 | Production system and method of sec-butyl acetate |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1202480A (en) * | 1998-05-22 | 1998-12-23 | 华南理工大学 | Process for synthesizing isopropyl salicylate |
| CN101143819A (en) * | 2007-10-16 | 2008-03-19 | 胡先念 | Method for preparing sec-butyl acetate |
| CN104557524A (en) * | 2013-10-22 | 2015-04-29 | 中国石油化工股份有限公司 | Production method of ethyl acetate |
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2015
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1202480A (en) * | 1998-05-22 | 1998-12-23 | 华南理工大学 | Process for synthesizing isopropyl salicylate |
| CN101143819A (en) * | 2007-10-16 | 2008-03-19 | 胡先念 | Method for preparing sec-butyl acetate |
| CN104557524A (en) * | 2013-10-22 | 2015-04-29 | 中国石油化工股份有限公司 | Production method of ethyl acetate |
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