CN101665455B - Method for preparing isooctyl thioglycolate by adopting tail liquid in the production process of O-alkyl-N-alkyl sulfide expelling carbamate - Google Patents
Method for preparing isooctyl thioglycolate by adopting tail liquid in the production process of O-alkyl-N-alkyl sulfide expelling carbamate Download PDFInfo
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- CN101665455B CN101665455B CN200910019058XA CN200910019058A CN101665455B CN 101665455 B CN101665455 B CN 101665455B CN 200910019058X A CN200910019058X A CN 200910019058XA CN 200910019058 A CN200910019058 A CN 200910019058A CN 101665455 B CN101665455 B CN 101665455B
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Abstract
The invention discloses a method for preparing isooctyl thioglycolate by adopting tail liquid in the production process of O-alkyl-N-alkyl sulfide expelling carbamate, comprising the following steps: a. acidifying and purifying tail liquid, removing separated suspending organic matters; b. extracting the acidified liquid by an extracting agent, esterifying to obtain rough ester; c. carrying out reduced pressure distillation on the rough ester and obtaining the isooctyl thioglycolate. The method is characterized in that: in the extraction and esterification processes, isooctane is firstly taken as the extracting agent to extract and esterify the acidified liquid to obtain organic mixture; the organic mixture is taken as an extracting agent to extract and esterify the new acidified liquid; and the obtained organic mixture after extraction and esterification is taken as an extracting agent to extract and esterify the new acidified liquid at least once. The invention has the advantages of reasonable production process, raw material saving, low production cost and high product quality and is a reasonable method for recycling the tail liquid in the production process of the O-alkyl-N-alkyl sulfide expelling carbamate.
Description
Technical field
The present invention relates to chemical field, be specifically related to a kind of producing the method that O-alkyl-N-alkyl sulfide is recycled by the Thiovanic acid in the carbamate tail washings.
Background technology
Isooctyl mercaptoacetate is a kind of novel nontoxic additives for plastics, is a kind of thermo-stabilizer of plastics widespread use in the course of processing such as PVC, and along with the fast development of polymeric material field, the demand of isooctyl mercaptoacetate also increased thereupon in recent years.At present the preparation method of isooctyl mercaptoacetate all exists material cost high, complex manufacturing, and problem such as the production cycle is long.And production technology and market are controlled by developed countries always.
O-alkyl-N-alkyl sulfide is a kind of thiourethane by carbamate; In of the production of O-alkyl-N-alkyl sulfide by thiourethanes such as carbamates, can produce a large amount of waste water (tail washings), follow the ratio of product to be about 6: 1; Contain the higher Thiovanic acid of concentration in the waste water, content is about 8～14%.If the therefore unreasonable processing of this part waste water and discharging not only can cause environmental pollution, also can cause certain wasting of resources.And utilize the Thiovanic acid in the tail washings to reclaim the preparation isooctyl mercaptoacetate, and not only can reach recycling to Thiovanic acid in the thiourethane tail washings, can also solve the market requirement of present isooctyl mercaptoacetate.Publication number is in the CN1105664A patent documentation; A kind of method that the Thiovanic acid tail washings prepares isooctyl mercaptoacetate that contains of producing thiourethane of utilizing is provided; This method is earlier tail washings to be carried out acidifying and extracts organic impurity wherein; With isooctyl alcohol tail washings is carried out counter-current extraction then and get thick ester, obtain isooctyl mercaptoacetate after the thick ester underpressure distillation.Utilize this method to produce isooctyl mercaptoacetate, Thiovanic acid and ester content are low in the thick ester that obtains after the extraction, also must in the organic phase of load Thiovanic acid, add the Thiovanic acid of high density before the esterification, have increased production cost; And during the organic substance in removing acidizing fluid, use volatile organic solvents such as sherwood oil, ether, environment has been caused repeated contamination again.
Summary of the invention
Technical problem to be solved by this invention is: to the deficiency that the recovery technology of Thiovanic acid in the thiourethane tail washings is existed in the prior art; Provide a kind of tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate to prepare the method for isooctyl mercaptoacetate, this working method has low, the high product quality advantages of production cost.
For solving the problems of the technologies described above, technical scheme of the present invention is:
The tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate prepares the method for isooctyl mercaptoacetate, comprises the steps:
A, to said tail washings acidification to PH＜3, remove suspended organic matter, obtain purified acidizing fluid;
B, said acidizing fluid is extracted and esterification with extraction agent, obtain thick ester;
C, thick ester is carried out underpressure distillation purify, obtain isooctyl mercaptoacetate;
Among the step b, at first use isooctyl alcohol, acidizing fluid is extracted with esterification obtain organic mixture as extraction agent; Use said organic mixture as extraction agent then, new acidizing fluid is extracted and esterification; Said as extraction agent new acidizing fluid the extraction with the process of esterification with the organic mixture that obtains after extraction and the esterification carried out once at least.
Preferably, said as extraction agent new acidizing fluid the extraction with the process of esterification with the organic mixture that obtains after extraction and the esterification carried out 1～7 time.
Preferably, in step b, before each esterification, adding tosic acid or sulfuric acid are made esterifying catalyst in the organic mixture that extraction obtains, and the addition of said catalyzer is 0.01～0.8wt% of said organic mixture.
Preferably, in step b, when making extraction agent with isooctyl alcohol, the volume ratio of isooctyl alcohol and acidizing fluid is 1: 0.5～1: 3.
Preferably, in described step c, at first purify carrying out underpressure distillation after the further esterification of said thick ester again.
Preferably, in step c, before the esterification, adding tosic acid or sulfuric acid are made esterifying catalyst in thick ester, and the addition of said catalyzer is 0.01～0.8wt% of said thick ester.
Preferably, described extraction is a counter-current extraction.
Owing to adopted technique scheme, the invention has the beneficial effects as follows:
1, utilizes the present invention to prepare isooctyl mercaptoacetate, make production O-alkyl-N-alkyl sulfide obtain rational and efficient use by the tail washings of carbamate, not only turn waste into wealth, and solved problem of environmental pollution.
2, the present invention reclaims the extraction of Thiovanic acid; Owing to taked repeatedly to extract repeatedly esterification method, and at the organic mixture that when extracting for the second time, uses once extraction and esterification to obtain as extraction agent, this " accumulation mode " not only reduced the usage quantity of isooctyl alcohol when extracting; And the content of isooctyl mercaptoacetate in the thick ester that finally obtains is significantly improved; Experimental data proves that the content of isooctyl mercaptoacetate can reach 85wt% in the thick ester, needn't in the organic phase of load Thiovanic acid, add the Thiovanic acid of high density during esterification; Just can obtain high-quality product; The conservation consumption has reduced production cost, will improve the industrial practicability level of O-alkyl-N-alkyl sulfide by the tail washings recovery of carbamate greatly.
3, during the suspended organic matter matter of the present invention in removing acidizing fluid, adopt the method for activated carbon filtration, solved in the prior art organic solvent the repeated contamination problem of environment.
4, the present invention has the advantage that production technique is reasonable, with short production cycle and production cost is low, and the isooctyl mercaptoacetate purity of utilizing the present invention to prepare reaches more than 99.5%, and quality reaches the imported product standard, alternative import.
Embodiment
Embodiment below in conjunction with concrete further sets forth the present invention.
Embodiment 1
(1) get the tail washings 1000ml that contains Thiovanic acid 9.5wt% and use hcl acidifying,, left standstill 2 days, then the tail washings after the acidifying is filtered with three grades of activated carbon columns to PH=2, the organism of deviating to suspend, the acidizing fluid that obtains is a clear solution, contains Thiovanic acid 9.3wt%.
(2) get the 200ml acidizing fluid 25 ℃ of temperature; At first extract with isooctyl alcohol; The volume ratio of isooctyl alcohol and acidizing fluid is 1: 1, in the extract that extraction obtains, adds the tosic acid that accounts for said extract 0.5wt% then and makees catalyzer, under 100 ℃ condition, carries out esterification; Get the new acidizing fluid of 200ml again, the organic mixture that obtains after the esterification as extraction agent, is extracted and esterification under same temperature condition; Use the organic mixture that obtains after extraction and the esterification as extraction agent new acidizing fluid to be extracted with the process of esterification and carry out 4 times, esterification time is 5 hours at every turn, finally obtains containing the thick ester 275g of isooctyl mercaptoacetate 75%, recovery of extraction 99.5wt%.
(3) under the vacuum condition, be 80 ℃ with thick ester in temperature, the tosic acid that adds 0.5wt% is made catalyzer, esterification 7 hours, and distillation is purified and is obtained isooctyl mercaptoacetate 193g, content 99.5wt% then.
Embodiment 2
(1) get the tail washings 1000ml that contains Thiovanic acid 8.2wt% and use sulfuric acid acidation,, left standstill 1 day, then the tail washings after the acidifying is filtered with three grades of activated carbon columns to PH=2, the organism of deviating to suspend, the acidizing fluid that obtains is a clear solution, contains Thiovanic acid 8.0wt%.
(2) get the 200ml acidizing fluid 40 ℃ of temperature; At first extract with isooctyl alcohol; The volume ratio of isooctyl alcohol and acidizing fluid is 1: 3, in the extract that extraction obtains, adds the tosic acid that accounts for said extract 0.01wt% then and makees catalyzer, under 150 ℃ condition, carries out esterification; Get the new acidizing fluid of 200ml again, the organic mixture that obtains after the esterification as extraction agent, is extracted and esterification under same temperature condition; Use the organic mixture that obtains after extraction and the esterification as extraction agent new acidizing fluid to be extracted with the process of esterification and carry out 1 time, esterification time is 6 hours at every turn, finally obtains containing the thick ester 268g of isooctyl mercaptoacetate 50%, recovery of extraction 98.5wt%.
(3) under the vacuum condition, be 60 ℃ with thick ester in temperature, the tosic acid that adds 0.8wt% is made catalyzer, esterification 9 hours, and distillation is purified and is obtained isooctyl mercaptoacetate 189g, content 99.6wt% then.
Embodiment 3
(1) gets the tail washings 2000ml that contains Thiovanic acid 11.2wt% and use hcl acidifying,, left standstill 3 days to PH=1.5; Then the tail washings after the acidifying is filtered with three grades of activated carbon columns; The organism of deviating to suspend, the acidizing fluid that obtains is a clear solution, contains Thiovanic acid 10.9wt%.
(2) get the 300ml acidizing fluid 30 ℃ of temperature; At first extract with isooctyl alcohol; The volume ratio of isooctyl alcohol and acidizing fluid is 1: 1, in the extract that extraction obtains, adds the tosic acid that accounts for said extract 0.6wt% then and makees catalyzer, under 120 ℃ condition, carries out esterification; Get the new acidizing fluid of 300ml again, the organic mixture that obtains after the esterification as extraction agent, is extracted and esterification under same temperature condition; The process that new acidizing fluid extracts with esterification is repeated 5 times as extraction agent with the organic mixture that obtains after extraction and the esterification, esterification time is 1 hour at every turn, finally obtains containing the thick ester 498g of isooctyl mercaptoacetate 79%, recovery of extraction 99.2wt%.
(3) under the vacuum condition, be 100 ℃ in temperature, add the catalyzer of doing of 0.2wt% thick ester, esterification 5 hours, distillation is purified and is obtained isooctyl mercaptoacetate 376g, content 99.7wt% then.
Embodiment 4
(1) get the tail washings 5000ml that contains Thiovanic acid 14.0wt% and use hcl acidifying,, left standstill 3 days, then the tail washings after the acidifying is filtered with three grades of activated carbon columns to PH=3, the organism of deviating to suspend, the acidizing fluid that obtains is a clear solution, contains Thiovanic acid 13.8wt%.
(2) get the 500ml acidizing fluid 10 ℃ of temperature; At first extract with isooctyl alcohol; The volume ratio of isooctyl alcohol and acidizing fluid is 1: 0.5, in the extract that extraction obtains, adds the tosic acid that accounts for said extract 0.8wt% then and makees catalyzer, under 60 ℃ condition, carries out esterification; Get the new acidizing fluid of 500ml again, the organic mixture that obtains after the esterification as extraction agent, is extracted and esterification under same temperature condition; New acidizing fluid is extracted and the process repetition of esterification 7 times as extraction agent with the organic mixture that obtains after extraction and the esterification; Each esterification time 3 hours; Finally obtain containing the thick ester 1062g of isooctyl mercaptoacetate 85wt%, recovery of extraction 99.0wt%.
(3) under the vacuum condition, be 150 ℃ with thick ester in temperature, the sulfuric acid that adds 0.01wt% is made catalyzer, esterification 1 hour, and distillation is purified and is obtained isooctyl mercaptoacetate 831g, content 99.7wt% then.
By in the tail washings of carbamate, yellow soda ash, sodium hydroxide, sodium sulphite, trithiocarbonic acid sodium and a spot of O-alkyl-N-alkyl sulfide that mainly contains Thioglycolic acid sodium salt, sodium-chlor and trace is by the condenses of carbamate, Thiovanic acid or oxide compound etc. at O-alkyl-N-alkyl sulfide.Thereby when the preparation isooctyl mercaptoacetate, need that at first tail washings is carried out removal of impurities and handle, because of tail washings is an alkalescence, need add sulfuric acid or hcl acidifying, the acidifying tail washings is left standstill appropriate time, be generally 1～3 day, remove organic impurity then.
Among the present invention; Use three level active carbon posts to filter the method for removing when removing organic impurity; Replaced using in the prior art volatile organic solvent method of extraction such as hydro carbons or ethers of low carbon chain such as sherwood oil, ether, avoided the repeated contamination problem of volatile organic solvent environment.
After the tail washings acidifying removal of impurities, the Thiovanic acid with in the extraction agent extraction acidizing fluid obtains thick ester, and inorganics and impurity are stayed in the water collection tail and is able to separate, and said extraction is a counter-current extraction.The present invention reclaims the extraction of Thiovanic acid, has taked repeatedly to extract repeatedly esterification method.When repeatedly extracting, use isooctyl alcohol as extraction agent the first time, and the organic mixture that all the use last time extracts and esterification obtains of extraction for the second time is as extraction agent certainly; Acidizing fluid to new extracts; Accomplished the reasonable utilization to raw materials such as isooctyl alcohol, the thick ester content that finally obtains can reach 85wt%, and recovery of extraction is more than the 98.5wt%; Basically reached the abundant recovery to Thiovanic acid, extraction temperature is controlled to be 10～40 ℃.When esterification, needn't in the organic phase of load Thiovanic acid, add the Thiovanic acid of high density, just can obtain high-load product, reduce production cost, improve quality product.
Further esterification of thick ester that obtains and underpressure distillation are purified, and esterification temperature is controlled to be 60～150 ℃, esterification time 1～9 hour, and obtaining content is the above isooctyl mercaptoacetate of 99.5wt%.
The present invention has the advantage that production technique is reasonable, with short production cycle and production cost is low.Utilize the present invention to prepare isooctyl mercaptoacetate, make production O-alkyl-N-alkyl sulfide obtain comprehensive utilization by the tail washings of carbamate, not only turn waste into wealth, and solved problem of environmental pollution.
The isooctyl mercaptoacetate quality product of utilizing the present invention to prepare reaches the imported product standard, alternative import.The present invention can be used to produce the recycling that the thiourethane class contains the tail washings of Thiovanic acid.
Claims (9)
1. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate prepares the method for isooctyl mercaptoacetate, comprises the steps:
A, to said tail washings acidification to pH＜3, remove suspended organic matter, obtain purified acidizing fluid;
B, said acidizing fluid is extracted and esterification with extraction agent, obtain thick ester;
C, thick ester is carried out underpressure distillation purify, obtain isooctyl mercaptoacetate; It is characterized in that:
Among the step b, at first use isooctyl alcohol, acidizing fluid is extracted with esterification obtain organic mixture as extraction agent; Use said organic mixture as extraction agent then, new acidizing fluid is extracted and esterification; Using the organic mixture that obtains after extraction and the esterification as extraction agent new acidizing fluid to be extracted with the process of esterification carries out once at least.
2. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate as claimed in claim 1 prepares the method for isooctyl mercaptoacetate, it is characterized in that: new acidizing fluid is extracted with the process of esterification as extraction agent with the organic mixture that obtains after extraction and the esterification and carry out 1～7 time.
3. O-alkyl-N-alkyl sulfide prepares isooctyl mercaptoacetate by the tail washings of carbamate the method for producing of using as claimed in claim 1; It is characterized in that: in step b; Before each esterification; Adding tosic acid or sulfuric acid are made esterifying catalyst in the organic mixture that extraction obtains, and the addition of said catalyzer is 0.01～0.8wt% of said organic mixture.
4. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate as claimed in claim 2 prepares the method for isooctyl mercaptoacetate, it is characterized in that:
In step b, when making extraction agent with isooctyl alcohol, the volume ratio of isooctyl alcohol and acidizing fluid is 1: 0.5～1: 3.
5. prepare the method for isooctyl mercaptoacetate like described any of claim 1 to 4 by the tail washings of carbamate with production O-alkyl-N-alkyl sulfide; It is characterized in that: in described step c, at first purify carrying out underpressure distillation after the further esterification of said thick ester again.
6. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate as claimed in claim 5 prepares the method for isooctyl mercaptoacetate, it is characterized in that: in step c,
Before the esterification, adding tosic acid or sulfuric acid are made esterifying catalyst in thick ester, and the addition of said catalyzer is 0.01～0.8wt% of said thick ester.
7. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate as claimed in claim 1 prepares the method for isooctyl mercaptoacetate, it is characterized in that:
In step a, use activated carbon filtration when removing suspended organic matter.
8. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate as claimed in claim 1 prepares the method for isooctyl mercaptoacetate, it is characterized in that:
In step a, what use during acidification is sulfuric acid or hydrochloric acid.
9. the tail washings of using production O-alkyl-N-alkyl sulfide to pursue carbamate as claimed in claim 1 prepares the method for isooctyl mercaptoacetate, and it is characterized in that: described extraction is a counter-current extraction.
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| CN200910019058XA CN101665455B (en) | 2009-09-27 | 2009-09-27 | Method for preparing isooctyl thioglycolate by adopting tail liquid in the production process of O-alkyl-N-alkyl sulfide expelling carbamate |
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| CN200910019058XA CN101665455B (en) | 2009-09-27 | 2009-09-27 | Method for preparing isooctyl thioglycolate by adopting tail liquid in the production process of O-alkyl-N-alkyl sulfide expelling carbamate |
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| CN101665455B true CN101665455B (en) | 2012-08-08 |
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| CN102229549B (en) * | 2011-05-16 | 2013-11-06 | 潍坊益华化工有限公司 | Method for preparing isooctyl mercaptoacetate |
| CN103130353B (en) * | 2011-11-25 | 2014-01-15 | 中国石油天然气股份有限公司 | Treatment method of high-calcium organic wastewater |
| CN102775333B (en) * | 2012-07-31 | 2014-07-16 | 烟台恒邦化工助剂有限公司 | Method for preparing isooctyl thioglycolate by utilizing thionocarbamate tail liquid |
| CN105237449A (en) * | 2015-11-09 | 2016-01-13 | 青岛联拓化工有限公司 | Method for preparing high-concentration mercaptoacetic acid from tail liquid of O-alkyl-N-alkyl thinocarbamate production |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1105664A (en) * | 1994-05-25 | 1995-07-26 | 沈阳矿冶研究所 | Preparation of isooctyl mercaptoacetate by using tailing liquor containing mercaptoacetic acid from production of thiourethane |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1105664A (en) * | 1994-05-25 | 1995-07-26 | 沈阳矿冶研究所 | Preparation of isooctyl mercaptoacetate by using tailing liquor containing mercaptoacetic acid from production of thiourethane |
Non-Patent Citations (2)
| Title |
|---|
| 曾湘晖等.巯基乙酸异辛酯的合成研究.《浙江化工》.2006,第37卷(第12期),第4-6页. * |
| 曾湘晖等.烷基硫氨酯系列捕收剂的合成及性能研究.《化工时刊》.2006,第20卷(第3期),第19-21页. * |
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