CN105218421A - A kind of production method of 3-thiohydracrylic acid - Google Patents
A kind of production method of 3-thiohydracrylic acid Download PDFInfo
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- CN105218421A CN105218421A CN201510605708.4A CN201510605708A CN105218421A CN 105218421 A CN105218421 A CN 105218421A CN 201510605708 A CN201510605708 A CN 201510605708A CN 105218421 A CN105218421 A CN 105218421A
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Abstract
The invention belongs to chemosynthesis technical field, be specifically related to a kind of production method of 3-thiohydracrylic acid.The production method of 3-thiohydracrylic acid of the present invention is with 30%NaHS solution, NaOH, SULPHUR POWDER for raw material, and be heated to 45 DEG C of insulation reaction, reaction solution is for subsequent use; Vinyl cyanide is dropped in above-mentioned steps reaction solution, temperature 40-45 DEG C in the hierarchy of control, in 45-50 DEG C of reaction after dropwising, obtain reaction mother liquor.In 31% hydrochloric acid, drip above-mentioned reaction mother liquor, 2-4h drips off; Dropwise rear 118-120 DEG C back flow reaction 6-12h, add iron powder and carry out reduction reaction, use solvent extraction process after reduction, reclaim ethylene dichloride and apply mechanically, under high vacuum condition, rectifying obtains high-content 3-thiohydracrylic acid finished product.The 3-thiohydracrylic acid that the production method of 3-thiohydracrylic acid of the present invention prepares, its content >=99.5%, product 3-thiohydracrylic acid total recovery >=96%.
Description
Technical field
The invention belongs to chemosynthesis technical field, be specifically related to a kind of production method of 3-thiohydracrylic acid.
Background technology
3-thiohydracrylic acid is the important industrial raw material of a class and important medicine intermediate, mainly contains mercaptan and the large class of thiophenol two.3-thiohydracrylic acid of many uses is medical chlormezanone (chlormezanone) intermediate, is also used as polyvinyl chloride (PVC) stabilizer; Equally can be used for transparent article in thioglycolic acid, its stability is very good, is better than other stablizers; It also can make oxidation inhibitor, catalyzer and biochemical reagents; Also can be used as the intermediate of medicine, agricultural chemicals and weedicide, can toxinicide be done, thiofide; Recent years, this product is widely used in the water reducer etc. of building trade.
Current 3-thiohydracrylic acid production line, mainly contains three kinds of synthetic routes:
1, vinyl cyanide method.Namely after vinyl cyanide and Sodium sulfhydrate addition reaction again through acidolysis, reduction, process and obtaining, present most of enterprise takes this route to produce, and the method general technology yield is lower, product quality is poor, colourity is high;
2, propylene acid system.Namely vinylformic acid and hydrogen sulfide are hydrolyzed after reacting again and obtain, and the method is under high pressure carried out, and facility investment is large, yield is low, produce more hydrogen sulfide, and it is more difficult to reclaim, and environmental pollution is large;
3,3-chloropropionic acid method.I.e. 3-chloropropionic acid and Na
2s
2o
3carry out nucleophilic substitution reaction acidolysis and obtaining again, the method raw materials cost is high, wastewater flow rate is large, environmental pollution is serious.
Patent CN1793117 discloses a kind of preparation method of 3-thiohydracrylic acid, using aqueous sodium hydroxide solution, Sodium sulfhydrate, as catalyzer sodium polysulphide mixing after, vinyl cyanide is added dropwise at 20-70 DEG C, insulation generates the mixed solution of multiple intermediate, then add hydrochloric acid and carry out acidifying, add zinc powder again to reduce, obtain the solution containing 3-thiohydracrylic acid; The described sodium polysulphide as catalyzer is NaSx, wherein x=1-6; The additional proportion of described each composition is as follows: the consumption mol ratio of sodium hydroxide is vinyl cyanide: sodium hydroxide=1: 0.2-0.8; The consumption mol ratio of Sodium sulfhydrate is vinyl cyanide: Sodium sulfhydrate=1: 1-2.5; Consumption as the sodium polysulphide of catalyzer is the 5-10% of vinyl cyanide weight.The consumption mol ratio of hydrochloric acid is vinyl cyanide: hydrochloric acid=1: 2-5; The consumption mol ratio of zinc powder is vinyl cyanide: zinc=1: 0.2-0.8.Applicant finds in practice, and the method yield is lower.
Summary of the invention
In order to solve above-mentioned technical problem, the invention provides a kind of production method of 3-thiohydracrylic acid.
The present invention is realized by following technical scheme:
A production method for 3-thiohydracrylic acid, comprises following step:
A NaHS solution, NaOH, SULPHUR POWDER add in 3000L reactor by () successively, open to stir and be heated to 38-42 DEG C to stop heating, and system is warming up to 45 DEG C naturally, insulation reaction 2-4h, and then lower the temperature 20 DEG C, reaction solution is for subsequent use; Be added drop-wise in above-mentioned reaction solution by vinyl cyanide, in the hierarchy of control, temperature 40-45 DEG C, 1-5h drip off, and then in 45-50 DEG C of insulation reaction 2h again, are down to room temperature, obtain reaction mother liquor;
B hydrochloric acid joins in 5000L reactor by (), in the reaction mother liquor that 55-65 DEG C drips step a and obtain, 2-4h drips off; Rapid temperature increases is to backflow, and after 118-120 DEG C of back flow reaction 6-12h, be cooled to less than 80 DEG C, reaction solution is for subsequent use;
Add iron powder in c reaction solution that () obtains to step b under 70-80 DEG C of condition, 1-5h adds, and is then cooled to less than 20 DEG C, and filter, filtrate enters lower step operation;
D above-mentioned filtrate is squeezed in extraction kettle by (), then use ethylene dichloride continuous extraction 2 times, merges ethylene dichloride layer, squeeze in still kettle, first normal pressure reclaims ethylene dichloride and applies mechanically, and then carries out rectifying in high vacuum conditions, collect 118-130 DEG C of cut, be 3-thiohydracrylic acid finished product; Water layer process is recycled.
In the production method of above-mentioned 3-thiohydracrylic acid, in described step a, NaHS solution quality percentage concentration is 30%, NaHS solution, the consumption mass ratio of NaOH, SULPHUR POWDER, vinyl cyanide is 5:0.01-0.05:0.001-0.01:1.
In the production method of above-mentioned 3-thiohydracrylic acid, in described step b, the mass percent concentration of hydrochloric acid is 31%, and consumption is 10 times of vinyl cyanide consumption.
In the production method of above-mentioned 3-thiohydracrylic acid, in described step c, the consumption of iron powder is the 0.05%-0.1% of vinyl cyanide consumption.
In the production method of above-mentioned 3-thiohydracrylic acid, in described steps d, each extraction ethylene dichloride consumption is 10-20 times of vinyl cyanide consumption.
In the production method of above-mentioned 3-thiohydracrylic acid, in described step c, each extraction ethylene dichloride consumption is that vinyl cyanide is used
The production method of 3-thiohydracrylic acid, comprise following step:
Wherein, step a is addition operation, and in this operation, reaction equation is as follows:
Step b is hydrolyzing process, and this operation has side reaction to occur, and Sodium sulfhydrate and hydrochloric acid reaction generate sodium-chlor and hydrogen sulfide (using 32% absorbing by liquid caustic soda under tiny structure condition), and sodium hydroxide and hydrochloric acid reaction generate sodium-chlor and water;
Main reaction equation in this operation:
Side reaction equation in this operation:
NaOH+HCl—→NaCl+H
2O
NaHS+HCl—→NaCl+H
2S↑
NH
3+HCl—→NH
4Cl
Step c is reduction operation, and main reaction equation is
Side reaction equation is
Fe+2HCl→FeCl
2+H
2↑
Steps d is extraction process and distillation process.
Beneficial effect of the present invention is:
1, the 3-thiohydracrylic acid for preparing of the production method of 3-thiohydracrylic acid of the present invention, its content >=99.5%, product 3-thiohydracrylic acid total recovery >=96%.
2, elemental sulfur makees catalyzer and instead of sodium polysulphide, and activation treatment under certain temperature condition in advance before feeding intake, then the use that feeds intake, the 3-thiohydracrylic acid prepared like this, its yield is high, and product purity is high.
3, the object adding SULPHUR POWDER is as reaction suppressor, suppresses the generation of side reaction, and namely suppress the generation of sulfo-acrylonitrile and dithio vinyl cyanide, particularly sulfo-acrylonitrile cannot be reduced, thus improves yield;
4, iron powder reducing is compared and zinc powder reduction, and cost is lower, and yield is higher;
5, the production method of 3-thiohydracrylic acid of the present invention, environmentally friendly, and " three wastes " are easily administered, specific as follows:
(1) the heavily steaming, extracting sour water utilizes.Because still have the product be not extracted in a large number in extraction sour water, directly process discharge, the rising of environmental protection running cost or ambient water can be caused on the one hand to pollute, product yield declines on the other hand, sour water heavily steams utilization directly can improve product yield more than 15%, has substantially accomplished the zero release of processing wastewater;
(2), waste gas H
2the absorption of S.Waste gas H
2s utilizes special device specific absorption to reach more than 99.5%, and the sodium sulfocynanate generated is as prepared using, and waste gas can accomplish qualified discharge completely, meets environmental requirement;
, reaction generate ammonium chloride, sodium-chlor through be separated after, can sell as byproduct, danger solid waste less, entrust have qualification unit to dispose.
Embodiment
Below in conjunction with specific embodiment, the present invention is further described, so that those skilled in the art more understands the present invention, but does not therefore limit the present invention.
Embodiment 1
(a) addition operation
In this operation, NaHS solution quality percentage concentration is 30%, and the consumption mass ratio of each raw material NaHS solution, NaOH, SULPHUR POWDER, vinyl cyanide is 5:0.03:0.005:1.
1. the NaHS solution configured of metering, NaOH, SULPHUR POWDER are added in 3000L glassed steel reaction vessels successively, open to stir and be heated to 38-42 DEG C and stop heating, system is warming up to 45 DEG C naturally, insulation reaction 2-4h, then lower the temperature 20 DEG C, reaction solution is for subsequent use; Precise vinyl cyanide, pumps in elevated dosing vessel, and slowly drops to step 1. in reaction solution, in the hierarchy of control, temperature 40-45 DEG C, 1-5h drip off, then in 45-50 DEG C of insulation reaction 2h again, be down to room temperature, obtain reaction mother liquor, be transferred in header tank and participate in the next step;
(b) hydrolyzing process
In this operation, 31% hydrochloric acid consumption is 10 times of vinyl cyanide consumption.
Squeeze in 5000L reactor by 31% hydrochloric acid of metering, close exhaust-valve, open device for absorbing tail gas (absorption liquid is applied mechanically) and open reactor, start and stir, in the reaction mother liquor that 55-65 DEG C drips step a and obtain, 2-4h drips off; (drip Bi Wendu and naturally heat up about 80 DEG C) after dripping, rapid temperature increases is to backflow, after 118-120 DEG C of back flow reaction 6-12h, be cooled to less than 80 DEG C, this operation has side reaction to occur, Sodium sulfhydrate and hydrochloric acid reaction generate sodium-chlor and hydrogen sulfide (using 32% absorbing by liquid caustic soda under tiny structure condition), and sodium hydroxide and hydrochloric acid reaction generate sodium-chlor and water;
(c) hydrolyzing process
In this operation, the consumption of iron powder is 0.07% of vinyl cyanide consumption.
Under 70-80 DEG C of condition, add iron powder in above-mentioned system, 1-5h adds, and then lowers the temperature less than 20 DEG C, and filter, solids treatment, liquid enters lower step operation;
(d) extraction process and distillation process
In this operation, each extraction ethylene dichloride consumption is 10 times of vinyl cyanide consumption.
Above-mentioned filtrate is squeezed in extraction kettle, then with the ethylene dichloride continuous extraction of measuring 2 times, merge ethylene dichloride layer, squeeze in still kettle, first normal pressure reclaims ethylene dichloride and applies mechanically, and then carries out rectifying in high vacuum conditions, collects 118-130 DEG C of cut, be 3-thiohydracrylic acid finished product, water layer process is recycled.3-thiohydracrylic acid total recovery 98.6%, content 99.9%.
Embodiment 2
(a) addition operation
In this operation, NaHS solution quality percentage concentration is 30%, and the consumption mass ratio of each raw material NaHS solution, NaOH, SULPHUR POWDER, vinyl cyanide is 5:0.01:0.001:1.
1. the NaHS solution configured of metering, NaOH, SULPHUR POWDER are added in 3000L glassed steel reaction vessels successively, open to stir and be heated to 38-42 DEG C and stop heating, system is warming up to 45 DEG C naturally, insulation reaction 2-4h, then lower the temperature 20 DEG C, reaction solution is for subsequent use; Precise vinyl cyanide, pumps in elevated dosing vessel, and slowly drops to step 1. in reaction solution, in the hierarchy of control, temperature 40-45 DEG C, 1-5h drip off, then in 45-50 DEG C of insulation reaction 2h again, be down to room temperature, obtain reaction mother liquor, be transferred in header tank and participate in the next step;
(b) hydrolyzing process
In this operation, 31% hydrochloric acid consumption is 10 times of vinyl cyanide consumption.
Squeeze in 5000L reactor by 31% hydrochloric acid of metering, close exhaust-valve, open device for absorbing tail gas (absorption liquid is applied mechanically) and open reactor, start and stir, in the reaction mother liquor that 55-65 DEG C drips step a and obtain, 2-4h drips off; (drip Bi Wendu and naturally heat up about 80 DEG C) after dripping, rapid temperature increases is to backflow, after 118-120 DEG C of back flow reaction 6-12h, be cooled to less than 80 DEG C, this operation has side reaction to occur, Sodium sulfhydrate and hydrochloric acid reaction generate sodium-chlor and hydrogen sulfide (using 32% absorbing by liquid caustic soda under tiny structure condition), and sodium hydroxide and hydrochloric acid reaction generate sodium-chlor and water;
(c) hydrolyzing process
In this operation, the consumption of iron powder is 0.05% of vinyl cyanide consumption.
Under 70-80 DEG C of condition, add iron powder in above-mentioned system, 1-5h adds, and then lowers the temperature less than 20 DEG C, and filter, solids treatment, liquid enters lower step operation;
(d) extraction process and distillation process
In this operation, each extraction ethylene dichloride consumption is 10 times of vinyl cyanide consumption.
Above-mentioned filtrate is squeezed in extraction kettle, then with the ethylene dichloride continuous extraction of measuring 2 times, merge ethylene dichloride layer, squeeze in still kettle, first normal pressure reclaims ethylene dichloride and applies mechanically, and then carries out rectifying in high vacuum conditions, collects 118-130 DEG C of cut, be 3-thiohydracrylic acid finished product, water layer process is recycled.3-thiohydracrylic acid total recovery 96.8%, content 99.8%.
Embodiment 3
(a) addition operation
In this operation, NaHS solution quality percentage concentration is 30%, and the consumption mass ratio of each raw material NaHS solution, NaOH, SULPHUR POWDER, vinyl cyanide is 5:0.05:0.01:1.
1. the NaHS solution configured of metering, NaOH, SULPHUR POWDER are added in 3000L glassed steel reaction vessels successively, open to stir and be heated to 38-42 DEG C and stop heating, system is warming up to 45 DEG C naturally, insulation reaction 2-4h, then lower the temperature 20 DEG C, reaction solution is for subsequent use; Precise vinyl cyanide, pumps in elevated dosing vessel, and slowly drops to step 1. in reaction solution, in the hierarchy of control, temperature 40-45 DEG C, 1-5h drip off, then in 45-50 DEG C of insulation reaction 2h again, be down to room temperature, obtain reaction mother liquor, be transferred in header tank and participate in the next step;
(b) hydrolyzing process
In this operation, 31% hydrochloric acid consumption is 10 times of vinyl cyanide consumption.
Squeeze in 5000L reactor by 31% hydrochloric acid of metering, close exhaust-valve, open device for absorbing tail gas (absorption liquid is applied mechanically) and open reactor, start and stir, in the reaction mother liquor that 55-65 DEG C drips step a and obtain, 2-4h drips off; (drip Bi Wendu and naturally heat up about 80 DEG C) after dripping, rapid temperature increases is to backflow, after 118-120 DEG C of back flow reaction 6-12h, be cooled to less than 80 DEG C, this operation has side reaction to occur, Sodium sulfhydrate and hydrochloric acid reaction generate sodium-chlor and hydrogen sulfide (using 32% absorbing by liquid caustic soda under tiny structure condition), and sodium hydroxide and hydrochloric acid reaction generate sodium-chlor and water;
(c) hydrolyzing process
In this operation, the consumption of iron powder is 0.1% of vinyl cyanide consumption.
Under 70-80 DEG C of condition, add iron powder in above-mentioned system, 1-5h adds, and then lowers the temperature less than 20 DEG C, and filter, solids treatment, liquid enters lower step operation;
(d) extraction process and distillation process
In this operation, each extraction ethylene dichloride consumption is 20 times of vinyl cyanide consumption.
Above-mentioned filtrate is squeezed in extraction kettle, then with the ethylene dichloride continuous extraction of measuring 2 times, merge ethylene dichloride layer, squeeze in still kettle, first normal pressure reclaims ethylene dichloride and applies mechanically, and then carries out rectifying in high vacuum conditions, collects 118-130 DEG C of cut, be 3-thiohydracrylic acid finished product, water layer process is recycled.3-thiohydracrylic acid total recovery 98.2%, content 99.8%.
Reference examples 1 is prepared with reference to the method for patent CN1793117 embodiment 1
The preparation of synthesis liquid:
The Sodium sulfhydrate of 250 gram 30%, 12 grams of caustic soda, the water of 20 grams, 3 grams of catalyzer sodium disulfides are added reactor and stir, adds 54 grams of acrylonitrile reactors at 25 DEG C, add insulation reaction 10 hours.
Acidifying:
The technical hydrochloric acid 450 grams that concentration is 30% is added, temperature rising reflux 3 hours in above-mentioned synthesis liquid.
Reduction:
Above-mentioned acidizing fluid is cooled to 30 DEG C, adds zinc powder 40 grams reaction, is warming up to 100 DEG C and maintains 0.5 hour.
Extraction, distillation:
Above-mentioned reduced liquid adds toluene 500 grams stirring, layering, after upper liquid Distillation recovery toluene, then underpressure distillation, finally collect a 15mmHg110-111 DEG C fraction and namely obtain product.
3-thiohydracrylic acid total recovery 85.4%, content 96.5%.
Claims (5)
1. a production method for 3-thiohydracrylic acid, comprises following step:
A NaHS solution, NaOH, SULPHUR POWDER add in 3000L reactor by () successively, open to stir and be heated to 38-42 DEG C to stop heating, and system is warming up to 45 DEG C naturally, insulation reaction 2-4h, and then lower the temperature 20 DEG C, reaction solution is for subsequent use; Be added drop-wise in above-mentioned reaction solution by vinyl cyanide, in the hierarchy of control, temperature 40-45 DEG C, 1-5h drip off, and then in 45-50 DEG C of insulation reaction 2h again, are down to room temperature, obtain reaction mother liquor;
B hydrochloric acid joins in 5000L reactor by (), in the reaction mother liquor that 55-65 DEG C drips step a and obtain, 2-4h drips off; Rapid temperature increases is to backflow, and after 118-120 DEG C of back flow reaction 6-12h, be cooled to less than 80 DEG C, reaction solution is for subsequent use;
Add iron powder in c reaction solution that () obtains to step b under 70-80 DEG C of condition, 1-5h adds, and is then cooled to less than 20 DEG C, and filter, filtrate enters lower step operation;
D above-mentioned filtrate is squeezed in extraction kettle by (), then use ethylene dichloride continuous extraction 2 times, merges ethylene dichloride layer, squeeze in still kettle, first normal pressure reclaims ethylene dichloride and applies mechanically, and then carries out rectifying in high vacuum conditions, collect 118-130 DEG C of cut, be 3-thiohydracrylic acid finished product; Water layer process is recycled.
2. the production method of 3-thiohydracrylic acid as claimed in claim 1, it is characterized in that, in described step a, NaHS solution quality percentage concentration is 30%, NaHS solution, the consumption mass ratio of NaOH, SULPHUR POWDER, vinyl cyanide is 5:0.01-0.05:0.001-0.01:1.
3. the production method of 3-thiohydracrylic acid as claimed in claim 1, it is characterized in that, in described step b, the mass percent concentration of hydrochloric acid is 31%, and consumption is 10 times of vinyl cyanide consumption.
4. the production method of 3-thiohydracrylic acid as claimed in claim 1, it is characterized in that, in described step c, the consumption of iron powder is the 0.05%-0.1% of vinyl cyanide consumption.
5. the production method of 3-thiohydracrylic acid as claimed in claim 1, is characterized in that, in described steps d, each extraction ethylene dichloride consumption is 10-20 times of vinyl cyanide consumption.
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