CN1304925A - Process for depolymerizing butanediol tere-phthalate with methanol - Google Patents
Process for depolymerizing butanediol tere-phthalate with methanol Download PDFInfo
- Publication number
- CN1304925A CN1304925A CN00125914A CN00125914A CN1304925A CN 1304925 A CN1304925 A CN 1304925A CN 00125914 A CN00125914 A CN 00125914A CN 00125914 A CN00125914 A CN 00125914A CN 1304925 A CN1304925 A CN 1304925A
- Authority
- CN
- China
- Prior art keywords
- depolymerization
- methyl alcohol
- polybutylene terephthalate
- terephthalate
- drying
- 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.)
- Granted
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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
A process for depolymerizing poly (butanediol tere-phthalate) with methanol features that said raw material is depolymerized using methanol as depolymerizing agent at 230-350 deg.C and 2-20 MPa for 0.5-10 hr to obtain dimethyl tere-phthalate and 1,4-butanediol. Its advantages are high selectivity of monomer, simple process, and high content of monomer in the resultant.
Description
The invention belongs to the recoverying and utilizing method of waste, relate in particular to a kind of method of methyl alcohol depolymerization polybutylene terephthalate.
Polybutylene terephthalate is a kind of important engineering plastics; it has good heat-resistant; be widely used in electronics, electric, Business Machine, fiber optic cables protective sleeve, nerf bar, spandex fiber etc.; polybutylene terephthalate is industrial to be by dimethyl terephthalate (DMT) or terephthalic acid and 1, and the 4-butyleneglycol carries out polycondensation preparation.In recent years, this emerging engineering plastics volume of production and marketing of polybutylene terephthalate increases with the rate of growth of 25-30%, corresponding used polybutylene terephthalate waste increases thereupon, therefore needs to consider the recoverying and utilizing method of waste and old polybutylene terephthalate.
The research of the depolymerization method of at present relevant polyethylene terephthalate is commonplace, (see patent US 3 321 510 as sour water solution (seeing patent US 3 952 053), alkaline water solution (seeing patent GB 822 834), ethylene glycol depolymerization (seeing patent JP 06 248 646), methyl alcohol depolymerization, Eur.0 662 466 Al, GB 2 041 916) etc. method, but the depolymerization method of polybutylene terephthalate is not appeared in the newspapers by literature search as yet.
The object of the present invention is to provide that a kind of process is simple, the method for the higher methyl alcohol depolymerization polybutylene terephthalate of monomers dimethyl terephthalate one way selectivity and purity in the product.
The present invention is achieved in that with methyl alcohol as depolymerizing agent, is 230-350 ℃ with waste and old poly-terephthalyl alcohol butanediol ester in the depolymerization temperature, depolymerization pressure is under the 2.0-20.0MPa depolymerization 0.5-10 hour, and reaction product is rutgers and 1,4 butyleneglycol.
Concrete steps of the present invention are as follows:
(1) will be ground into the particle of 5.0-10 millimeter through the waste and old polybutylene terephthalate of washing, drying is removed impurity, stand-by;
(2) particle that step (1) is obtained and methyl alcohol are by 1: weight ratio (3-12) is added in the autoclave that has whipping appts;
(3) feed inert gas replacement and go out the interior oxygen of reaction system;
(4) then reaction system is warming up between 230-350 ℃, depolymerization pressure is 2.0-20.0MPa, and the depolymerization time is 0.5-10 hour;
(5) after depolymerization reaction is finished, reaction system is cooled to room temperature, an amount of methanol wash is used in crystallization, filter, be drying to obtain solid product, i.e. dimethyl terephthalate (DMT), filtrate through rectifying separation can get purity higher 1,4-butyleneglycol and methyl alcohol, methyl alcohol are also reusable.
Aforesaid polybutylene terephthalate raw material and methyl alcohol weight ratio can be 1: (3-10).
Aforesaid depolymerization temperature can be 260-290 ℃.
Aforesaid depolymerization pressure can be 8.0-12.0MPa.
The aforesaid depolymerization time can be 0.5-2.0 hour.
Aforesaid rare gas element is nitrogen or argon gas.
The present invention compared with prior art has the following advantages:
1. the present invention has proposed the chemical depolymerization technology of waste and old polybutylene terephthalate first, and depolymerization process and depolymerization aftertreatment technology are simple, and the content of non-target product is lower in the depolymerization product;
2. during depolymerization, depolymerization speed is fast under supercritical state, the degree of depolymerizaton of monomeric products yield height and good, the waste and old polybutylene terephthalate polyester of selectivity can be greater than 99% for present method;
3. by 1 of present technique gained, the 4-butyleneglycol can be used for regrouping with dimethyl terephthalate (DMT) through further purifying, generates new polybutylene terephthalate; Gained methyl alcohol can be used as the depolymerizing agent of depolymerization reaction again;
4. present technique need not added catalyzer in implementing production process, and also without bronsted lowry acids and bases bronsted lowry, three-waste free discharge is the green process that turns waste into wealth.
Embodiments of the invention are as follows:
Embodiment 1
Be equipped with one and add pretreated waste and old polybutylene terephthalate particle 5.94 grams and 47.52 such as to remove impurity through washing, drying in the autoclave of devices such as stirring, temperature control and restrain methyl alcohol, remaining oxygen in the nitrogen replacement reaction system, heat up then, start agitator, heating.The afterreaction system was warming up to 240 ℃ in 10 minutes, and system pressure rises to 4.0MPa.Be reflected at carry out 8.0 hours under this condition after, cooling, crystallization, filtration, methanol wash, be weighed as after the gained solid product drying 5.50 the gram.The selectivity of monomers dimethyl terephthalate is 95.1% in the solid product, contained insolubles is about 1.2%, terephthalic acid dibutylene glycol ester and methyl, hydroxyl-butyl bis--terephthalate contains 3.7% approximately, and polybutylene terephthalate polyester degree of depolymerizaton can reach 96.3%.
Embodiment 2
The depolymerization appointed condition is pressed embodiment 1, adds 9.90 grams in the autoclave and removes pretreated waste and old polybutylene terephthalate particle and 39.60 gram methyl alcohol such as impurity through washing, drying.Heat up, stir, boost, undertaken by the step of embodiment 1, depolymerization reaction is after carrying out 8.0 hours under 270 ℃, 6.0MPa, and cooling, crystallization, filtration, methanol wash are weighed as 9.55 grams after the gained solid product drying.The selectivity of monomers dimethyl terephthalate is 96.6% in the solid product, contained insolubles is about 0.9%, terephthalic acid dibutylene glycol ester and methyl, hydroxyl-butyl bis--terephthalate contains 2.4% approximately, and polybutylene terephthalate polyester degree of depolymerizaton can reach 99.1%.
Embodiment 3
The depolymerization appointed condition is pressed embodiment 1, adds 11.88 grams in the autoclave and removes pretreated waste and old polybutylene terephthalate particle and 47.52 gram methyl alcohol such as impurity through washing, drying.Heat up, stir, boost, undertaken by the step of embodiment 1, depolymerization reaction is after carrying out 60 minutes under 270 ℃, 10.0MPa, and cooling, crystallization, filtration, methanol wash are weighed as 11.36 grams after the gained solid product drying.The selectivity of monomers dimethyl terephthalate is 98.93% in the solid product, substantially do not contain terephthalic acid dibutylene glycol ester and methyl, hydroxyl-impurity such as butyl bis--terephthalate, contained insolubles is about 0.45%, and polybutylene terephthalate polyester degree of depolymerizaton can reach 99.03%.
Embodiment 4
The depolymerization appointed condition is pressed embodiment 1, adds 7.92 grams in the autoclave and removes pretreated waste and old polybutylene terephthalate particle and 47.52 gram methyl alcohol such as impurity through washing, drying.Heat up, stir, boost, undertaken by the step of embodiment 1, depolymerization reaction is after carrying out 60 minutes under 270 ℃, 11.0MPa, and cooling, crystallization, filtration, methanol wash are weighed as 7.63 grams after the gained solid product drying.The selectivity of monomers dimethyl terephthalate is 99.25% in the solid product, substantially do not contain terephthalic acid dibutylene glycol ester and methyl, hydroxyl-impurity such as butyl bis--terephthalate, contained insolubles is about 0.2%, and polybutylene terephthalate polyester degree of depolymerizaton can reach 99.37%.
Embodiment 5
The depolymerization appointed condition is pressed embodiment 1, adds 13.86 grams in the autoclave and removes pretreated waste and old polybutylene terephthalate particle and 55.44 gram methyl alcohol such as impurity through washing, drying.Heat up, stir, boost, undertaken by the step of embodiment 1, depolymerization reaction is after carrying out 60 minutes under 260 ℃, 9.0MPa, and cooling, crystallization, filtration, methanol wash are weighed as 13.21 grams after the gained solid product drying.The selectivity of monomers dimethyl terephthalate is 98.10% in the solid product, substantially do not contain terephthalic acid dibutylene glycol ester and methyl, hydroxyl-impurity such as butyl bis--terephthalate, contained insolubles is about 0.6%, and polybutylene terephthalate polyester degree of depolymerizaton can reach 98.51%.
Claims (6)
1. the method for a methyl alcohol depolymerization polybutylene terephthalate is characterized in that step is as follows:
(1) will be ground into the particle of 5.0-10 millimeter through the waste and old polybutylene terephthalate that washs, drying is removed impurity, stand-by;
(2) particle that step (1) is obtained and methyl alcohol are by 1: weight ratio (3-12) is added in the autoclave that has whipping appts;
(3) feed inert gas replacement and go out the interior oxygen of reaction system;
(4) then reaction system is warming up between 230-350 ℃, depolymerization pressure is 2.0-20.0MPa, and the depolymerization time is 0.5-10 hour;
(5) after depolymerization reaction is finished, reaction system is cooled to room temperature, an amount of methanol wash is used in crystallization, filter, be drying to obtain solid product, i.e. dimethyl terephthalate (DMT), filtrate through rectifying separation can get purity higher 1,4-butyleneglycol and methyl alcohol, methyl alcohol are also reusable.
2. the method for a kind of methyl alcohol depolymerization polybutylene terephthalate as claimed in claim 1 is characterized in that polybutylene terephthalate raw material and methyl alcohol weight ratio are 1: (3-10).
3. the method for a kind of methyl alcohol depolymerization polybutylene terephthalate as claimed in claim 1 is characterized in that described depolymerization temperature is 260-290 ℃.
4. the method for a kind of methyl alcohol depolymerization polybutylene terephthalate as claimed in claim 1 is characterized in that described depolymerization pressure is 8.0-12.0MPa.
5. the method for a kind of methyl alcohol depolymerization polybutylene terephthalate as claimed in claim 1 is characterized in that the described depolymerization time is 0.5-2.0 hour.
6. the method for a kind of methyl alcohol depolymerization polybutylene terephthalate as claimed in claim 1 is characterized in that described rare gas element is nitrogen or argon gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB001259148A CN1142132C (en) | 2000-08-18 | 2000-08-18 | Process for depolymerizing butanediol tere-phthalate with methanol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB001259148A CN1142132C (en) | 2000-08-18 | 2000-08-18 | Process for depolymerizing butanediol tere-phthalate with methanol |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1304925A true CN1304925A (en) | 2001-07-25 |
| CN1142132C CN1142132C (en) | 2004-03-17 |
Family
ID=4591690
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB001259148A Expired - Fee Related CN1142132C (en) | 2000-08-18 | 2000-08-18 | Process for depolymerizing butanediol tere-phthalate with methanol |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1142132C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101993164B (en) * | 2009-08-25 | 2011-12-28 | 慈溪市洁达纳米复合材料有限公司 | Method for treating and recovering wastewater generated during sharpening polybutylene terephthalate (PBT) brush threads |
| CN109134244A (en) * | 2018-09-26 | 2019-01-04 | 东华大学 | A kind of biodegrading process of waste and old polyester |
| CN110240426A (en) * | 2019-05-22 | 2019-09-17 | 湖南昌迪环境科技有限公司 | A kind of cement slurry additive and its application and cement production process |
| CN110255947A (en) * | 2019-05-22 | 2019-09-20 | 湖南昌迪环境科技有限公司 | A kind of grinding aid and its application |
-
2000
- 2000-08-18 CN CNB001259148A patent/CN1142132C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101993164B (en) * | 2009-08-25 | 2011-12-28 | 慈溪市洁达纳米复合材料有限公司 | Method for treating and recovering wastewater generated during sharpening polybutylene terephthalate (PBT) brush threads |
| CN109134244A (en) * | 2018-09-26 | 2019-01-04 | 东华大学 | A kind of biodegrading process of waste and old polyester |
| CN110240426A (en) * | 2019-05-22 | 2019-09-17 | 湖南昌迪环境科技有限公司 | A kind of cement slurry additive and its application and cement production process |
| CN110255947A (en) * | 2019-05-22 | 2019-09-20 | 湖南昌迪环境科技有限公司 | A kind of grinding aid and its application |
| CN110255947B (en) * | 2019-05-22 | 2022-03-04 | 湖南昌迪环境科技有限公司 | Grinding aid and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1142132C (en) | 2004-03-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2021004069A1 (en) | Method for recycling waste polyester material | |
| Han | Depolymerization of PET bottle via methanolysis and hydrolysis | |
| CN110527138B (en) | Continuous alcoholysis recovery method of waste polyester | |
| EP3783057B1 (en) | Recovery method for waste polyester material performed by means of continuous alcoholysis and continuous transesterification | |
| KR100746678B1 (en) | Dimethyl terephthalate composition and process for producing the same | |
| JPWO2003008479A1 (en) | Catalyst for producing polyester and method for producing polyester using the same | |
| CN101906218A (en) | Method for recycling polyester waste by normal-pressure alcoholysis | |
| CN112679464A (en) | Method for preparing lactide with high yield | |
| CN1142132C (en) | Process for depolymerizing butanediol tere-phthalate with methanol | |
| JP4262995B2 (en) | Method for producing terephthalic acid cake suitable for polyester raw material | |
| CN1190408C (en) | Process for producing ester | |
| JP4330918B2 (en) | How to recycle polyester waste | |
| EP0662466B1 (en) | Continuous process for the recovery of terephthalic acid from waste or used products of polyalkylene terephthalate polymers | |
| CN1304924A (en) | Process for depolymerizing waste glycol tere-phthalate | |
| EP2539332B1 (en) | Improved process for the preparation of l-lactide of high chemical yield and optical purity | |
| CN114890898B (en) | Method for recycling waste polyester based on alcoholysis of two-component catalyst | |
| CN1445207A (en) | Method for recycling monomer of polypropylene glycol terephthalate | |
| EP1069145B1 (en) | Process for producing polyester using a distannoxane catalyst | |
| CN1162392C (en) | High-pressure waste TA converting process of preparing DMT | |
| US6717009B2 (en) | Method for making high-purity naphthalenedicarboxylic acid | |
| CN117185920A (en) | Method for degrading polyester, degradation product obtained by same and application of degradation product | |
| CN1721418A (en) | Method for catalytic synthesis of lactide from lactic acid | |
| CN115536629B (en) | Preparation method of glycolide | |
| JP3303370B2 (en) | Depolymerization method of aromatic polyester | |
| KR20230143522A (en) | Preparation method of bis(glycol) terephthalate and polyester resin using same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20040317 Termination date: 20120818 |