CN114890892B - Method for degrading polyester through film-falling flow alcoholysis - Google Patents
Method for degrading polyester through film-falling flow alcoholysis Download PDFInfo
- Publication number
- CN114890892B CN114890892B CN202210626557.0A CN202210626557A CN114890892B CN 114890892 B CN114890892 B CN 114890892B CN 202210626557 A CN202210626557 A CN 202210626557A CN 114890892 B CN114890892 B CN 114890892B
- Authority
- CN
- China
- Prior art keywords
- falling film
- alcoholysis
- polyester
- kettle
- 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.)
- Active
Links
- 238000006136 alcoholysis reaction Methods 0.000 title claims abstract description 73
- 229920000728 polyester Polymers 0.000 title claims abstract description 52
- 238000000034 method Methods 0.000 title claims abstract description 37
- 230000000593 degrading effect Effects 0.000 title abstract description 6
- 239000011552 falling film Substances 0.000 claims abstract description 90
- 238000006243 chemical reaction Methods 0.000 claims abstract description 29
- 239000007788 liquid Substances 0.000 claims abstract description 6
- 239000000463 material Substances 0.000 claims description 46
- 238000003756 stirring Methods 0.000 claims description 33
- 229910052751 metal Inorganic materials 0.000 claims description 24
- 239000002184 metal Substances 0.000 claims description 24
- 238000009826 distribution Methods 0.000 claims description 21
- 239000003054 catalyst Substances 0.000 claims description 20
- 150000003839 salts Chemical class 0.000 claims description 17
- 239000012295 chemical reaction liquid Substances 0.000 claims description 16
- 238000004140 cleaning Methods 0.000 claims description 15
- 238000001035 drying Methods 0.000 claims description 13
- LYCAIKOWRPUZTN-UHFFFAOYSA-N ethylene glycol Natural products OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 12
- -1 bottle flakes Substances 0.000 claims description 11
- 229910052799 carbon Inorganic materials 0.000 claims description 9
- 238000007599 discharging Methods 0.000 claims description 9
- 238000001914 filtration Methods 0.000 claims description 9
- 230000005540 biological transmission Effects 0.000 claims description 8
- 239000005416 organic matter Substances 0.000 claims description 8
- 238000004321 preservation Methods 0.000 claims description 8
- 239000002904 solvent Substances 0.000 claims description 8
- 239000002699 waste material Substances 0.000 claims description 8
- 239000010408 film Substances 0.000 claims description 7
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 7
- ZRALSGWEFCBTJO-UHFFFAOYSA-N Guanidine Chemical compound NC(N)=N ZRALSGWEFCBTJO-UHFFFAOYSA-N 0.000 claims description 6
- 239000004744 fabric Substances 0.000 claims description 6
- 239000002994 raw material Substances 0.000 claims description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 4
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 4
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 4
- 150000007942 carboxylates Chemical class 0.000 claims description 4
- 125000004185 ester group Chemical group 0.000 claims description 4
- 229910052700 potassium Inorganic materials 0.000 claims description 4
- 239000011591 potassium Substances 0.000 claims description 4
- 229910052725 zinc Inorganic materials 0.000 claims description 4
- 239000011701 zinc Substances 0.000 claims description 4
- CHJJGSNFBQVOTG-UHFFFAOYSA-N N-methyl-guanidine Natural products CNC(N)=N CHJJGSNFBQVOTG-UHFFFAOYSA-N 0.000 claims description 3
- 125000002619 bicyclic group Chemical group 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 3
- SWSQBOPZIKWTGO-UHFFFAOYSA-N dimethylaminoamidine Natural products CN(C)C(N)=N SWSQBOPZIKWTGO-UHFFFAOYSA-N 0.000 claims description 3
- 239000000835 fiber Substances 0.000 claims description 3
- 229920003023 plastic Polymers 0.000 claims description 3
- 239000004033 plastic Substances 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 2
- 150000004703 alkoxides Chemical class 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 238000002425 crystallisation Methods 0.000 claims description 2
- 230000008025 crystallization Effects 0.000 claims description 2
- 150000001924 cycloalkanes Chemical class 0.000 claims description 2
- 150000001925 cycloalkenes Chemical class 0.000 claims description 2
- 230000014759 maintenance of location Effects 0.000 claims description 2
- 229910001463 metal phosphate Inorganic materials 0.000 claims description 2
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- 239000010936 titanium Substances 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- 238000011084 recovery Methods 0.000 abstract description 3
- 238000000746 purification Methods 0.000 abstract description 2
- 230000035484 reaction time Effects 0.000 abstract description 2
- 238000007670 refining Methods 0.000 abstract description 2
- 239000000047 product Substances 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 9
- 239000012535 impurity Substances 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 7
- 238000011068 loading method Methods 0.000 description 7
- QPKOBORKPHRBPS-UHFFFAOYSA-N bis(2-hydroxyethyl) terephthalate Chemical compound OCCOC(=O)C1=CC=C(C(=O)OCCO)C=C1 QPKOBORKPHRBPS-UHFFFAOYSA-N 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- XRBXGZZMKCBTFP-UHFFFAOYSA-N 4-(2,2-dihydroxyethoxycarbonyl)benzoic acid Chemical compound OC(O)COC(=O)C1=CC=C(C(O)=O)C=C1 XRBXGZZMKCBTFP-UHFFFAOYSA-N 0.000 description 5
- ZOIORXHNWRGPMV-UHFFFAOYSA-N acetic acid;zinc Chemical compound [Zn].CC(O)=O.CC(O)=O ZOIORXHNWRGPMV-UHFFFAOYSA-N 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 239000004246 zinc acetate Substances 0.000 description 5
- 238000004064 recycling Methods 0.000 description 4
- JABYJIQOLGWMQW-UHFFFAOYSA-N undec-4-ene Chemical compound CCCCCCC=CCCC JABYJIQOLGWMQW-UHFFFAOYSA-N 0.000 description 4
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000007062 hydrolysis Effects 0.000 description 3
- 238000006460 hydrolysis reaction Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- LWIHDJKSTIGBAC-UHFFFAOYSA-K tripotassium phosphate Chemical compound [K+].[K+].[K+].[O-]P([O-])([O-])=O LWIHDJKSTIGBAC-UHFFFAOYSA-K 0.000 description 2
- FTTATHOUSOIFOQ-UHFFFAOYSA-N 1,2,3,4,6,7,8,8a-octahydropyrrolo[1,2-a]pyrazine Chemical compound C1NCCN2CCCC21 FTTATHOUSOIFOQ-UHFFFAOYSA-N 0.000 description 1
- PMJNSBRTFWZKGI-UHFFFAOYSA-N 4-(3,3-dihydroxypropoxycarbonyl)benzoic acid Chemical compound OC(O)CCOC(=O)C1=CC=C(C(O)=O)C=C1 PMJNSBRTFWZKGI-UHFFFAOYSA-N 0.000 description 1
- CBLGXJKSPMNSRJ-UHFFFAOYSA-N 4-(4,4-dihydroxybutoxycarbonyl)benzoic acid Chemical compound OC(O)CCCOC(=O)C1=CC=C(C(O)=O)C=C1 CBLGXJKSPMNSRJ-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000005915 ammonolysis reaction Methods 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- CDQSJQSWAWPGKG-UHFFFAOYSA-N butane-1,1-diol Chemical compound CCCC(O)O CDQSJQSWAWPGKG-UHFFFAOYSA-N 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000007857 degradation product Substances 0.000 description 1
- 150000002009 diols Chemical class 0.000 description 1
- 230000035622 drinking Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000010297 mechanical methods and process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000007344 nucleophilic reaction Methods 0.000 description 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 229910000160 potassium phosphate Inorganic materials 0.000 description 1
- 235000011009 potassium phosphates Nutrition 0.000 description 1
- 125000002924 primary amino group Chemical class [H]N([H])* 0.000 description 1
- 230000005588 protonation Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007142 ring opening reaction Methods 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- IMNIMPAHZVJRPE-UHFFFAOYSA-N triethylenediamine Chemical compound C1CN2CCN1CC2 IMNIMPAHZVJRPE-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/03—Preparation of carboxylic acid esters by reacting an ester group with a hydroxy group
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/14—Phosphorus; Compounds thereof
- B01J27/16—Phosphorus; Compounds thereof containing oxygen, i.e. acids, anhydrides and their derivates with N, S, B or halogens without carriers or on carriers based on C, Si, Al or Zr; also salts of Si, Al and Zr
- B01J27/18—Phosphorus; Compounds thereof containing oxygen, i.e. acids, anhydrides and their derivates with N, S, B or halogens without carriers or on carriers based on C, Si, Al or Zr; also salts of Si, Al and Zr with metals other than Al or Zr
- B01J27/1802—Salts or mixtures of anhydrides with compounds of other metals than V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, e.g. phosphates, thiophosphates
- B01J27/1806—Salts or mixtures of anhydrides with compounds of other metals than V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, e.g. phosphates, thiophosphates with alkaline or alkaline earth metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0201—Oxygen-containing compounds
- B01J31/0211—Oxygen-containing compounds with a metal-oxygen link
- B01J31/0212—Alkoxylates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0234—Nitrogen-, phosphorus-, arsenic- or antimony-containing compounds
- B01J31/0235—Nitrogen containing compounds
- B01J31/0244—Nitrogen containing compounds with nitrogen contained as ring member in aromatic compounds or moieties, e.g. pyridine
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0234—Nitrogen-, phosphorus-, arsenic- or antimony-containing compounds
- B01J31/0235—Nitrogen containing compounds
- B01J31/0245—Nitrogen containing compounds being derivatives of carboxylic or carbonic acids
- B01J31/0251—Guanidides (R2N-C(=NR)-NR2)
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/04—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing carboxylic acids or their salts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/19—Catalysts containing parts with different compositions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
- B01J2231/40—Substitution reactions at carbon centres, e.g. C-C or C-X, i.e. carbon-hetero atom, cross-coupling, C-H activation or ring-opening reactions
- B01J2231/49—Esterification or transesterification
-
- 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
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
The invention relates to the technical field of polyester recovery, and discloses a method for degrading polyester by falling film flow. According to the method disclosed by the invention, the polyester is subjected to alcoholysis, the alcoholysis reaction efficiency is high, the reaction temperature is low, the reaction time is short, the product purity is high, the refining and purification are easy, and the alcoholysis liquid can be recycled after being treated.
Description
Technical Field
The invention relates to the technical field of polyester recovery, in particular to a method for degrading polyester by falling film flow alcoholysis.
Background
The polyester prepared by the gradual polymerization principle of acid and alcohol is widely applied to various fields such as plastics, packaging containers, films, fibers, fabrics, pipes, sheets and the like due to the fact that the raw materials for production are easy to obtain, the large-scale production technology is mature, the cost is low, and the comprehensive performance of the product is outstanding. New production is increasing since the 21 st century. It is counted that only the world in 2020 has consumed polyester up to about 8000 ten thousand tons in the field of textile clothing and drinking bottle flakes. The polyester material provides convenience for life of people, but solid waste pollution caused by use is more and more serious, and the degradation resistance of the polyester material causes the serious damage to the ecological environment of the earth. The recycling of polyester materials has become an important topic in the global sustainable development.
At present, most of the recycling of polyester materials is carried out by degrading after being treated by a simple physical method or a mechanical method, and the recycling is mainly used as low-end products such as filling and cladding materials and the like to enter the market for circulation. The chemical method can thoroughly degrade the low molecular compound by the polyester material, and the degradation products can be reused as raw materials for synthesizing the polyester after being treated, so that the material can be recycled in the true sense.
The existing polyester chemical recovery method is mainly divided into hydrolysis, alcoholysis, ammonolysis and other methods according to the types of decomposers. The hydrolysis method has the advantages that the consumption of acid and alkali is large, a large amount of waste liquid exists, the depolymerization product of the hydrolysis method cannot be directly used as the raw material for regenerating the polyester, and the alcoholysis method has natural advantages due to the fact that the same or similar raw material is used in the polyester synthesis process, and particularly the alcoholysis method based on the monomer diol in the polyester synthesis is widely paid attention to in industry. However, the existing alcoholysis method has low reaction efficiency and low purity of target products, and development of an efficient alcoholysis method with few impurities of polyester material products is necessary.
Disclosure of Invention
The invention aims to overcome the defects of low reaction efficiency and high product purity in the existing polyester material alcoholysis method, and provides a method for degrading the polyester through falling film flow alcoholysis.
The specific technical scheme of the invention is as follows: a method for alcoholysis of polyester by falling film flow includes such steps as adding the pretreated polyester waste and solvent to stirring unit, adding part of catalyst, delivering the resultant reaction liquid to falling film reactor, and alcoholysis of polyester while flowing down film.
Compared with the traditional method for conducting alcoholysis reaction when the stirring blade in the reaction kettle is completely used for pushing the material to flow, the reaction liquid is used for conducting alcoholysis reaction by means of film forming flow on the liquid film support piece in the falling film kettle by means of gravity, so that the energy consumption of pushing force is greatly reduced, meanwhile, the film forming efficiency and surface updating of the material flowing are improved, the material does not generate backmixing due to the motion of the material in a plug flow, the solution residence time can be effectively regulated and controlled by changing the process, the alcoholysis time is greatly reduced, and the uniformity of alcoholysis reaction is improved. The stirring device designed at the bottom can further promote the further reaction of a small amount of materials which are not thoroughly subjected to alcoholysis while providing discharging power, so that the alcoholysis effect is improved.
Preferably, the polyester waste is any one or more of waste polyester plastics, bottle flakes, films, fibers, fabrics, melt discharge materials, pipes and sheets with the molecular weight exceeding 10000 and the ester group structure on the molecular main chain.
Preferably, the solvent is a glycol compound.
Preferably, the catalyst is a two-component catalyst comprising a metal salt and a nitrogen-containing polycyclic organic compound; wherein: the nitrogen-containing polycyclic organic matter is selected from one or more of cycloalkanes and cycloalkenes with two nitrogen elements and a ring number of 2 or 3; the metal salt is selected from one or more of metal alkoxides, metal carboxylates and metal phosphates of potassium, zinc, aluminum and titanium.
Compared with other types, the nitrogen-containing polycyclic organic compound under the limiting conditions can play a role in stabilizing the protonation site, enhance the attack on ester bonds on the polyester structure, and has better boiling point and less loss in the reaction compared with single-ring hydrocarbons. Furthermore, the team of the invention discovers in the research process that the combination of the several types of nitrogen-containing polycyclic organic matters and the specific several types of metal salts is used as a bi-component catalyst to catalyze alcoholysis of polyester, so that a synergistic effect can be generated, and the catalysis effect after compounding is far due to a single component. To further analyze this synergy mechanism, we conducted intensive studies, with the conclusion that: the nitrogen-containing polycyclic organic matter and hydroxyl in the solvent can form a hydrogen bond donor, and then are combined with functional groups in metal salts (such as carbonyl in zinc acetate) to form a complex, and the complex attacks ester bonds on polyester, so that the carbon matrix on the polyester molecular chain can be effectively improved, and the ester bonds are promoted to be broken. Therefore, the process of ester bond breakage can be greatly accelerated by the coordination of metal and nitrogen-containing polycyclic organic matters, and the polyester alcoholysis efficiency is remarkably improved.
Still further, the nitrogen-containing polycyclic organic matter is one or more selected from six-membered bicyclic guanidine, diazabicycloalkane compound; the metal salt is selected from one or more of metal carboxylates of potassium and zinc.
Preferably, the metal salt is added in a stirring device; the nitrogen-containing polycyclic organic matters are added into the stirring device and the falling film kettle respectively in two batches or added into the falling film kettle at one time.
The addition of a part of catalyst in the stirring device can lead the polyester waste to obtain primary alcoholysis, and the addition of the stirring device can improve the alcoholysis efficiency of the first stage, reduce the viscosity of the solution entering the falling film reaction kettle and improve the solution conveying and falling film flow rate.
On the other hand, in the process of deeper research, the team of the invention discovers that the adding time of the nitrogen-containing polycyclic organic matters has a remarkable influence on the catalytic effect. For example, in the test of adding a nitrogen-containing polycyclic organic compound together with a metal salt to a reaction system, it was found that the nitrogen-containing polycyclic organic compound is extremely susceptible to hydrolytic ring opening, and nucleophilic reaction is performed after formation of primary amine, resulting in a significant reduction in polyester degradation rate and monomer/prepolymer yield. Therefore, the nitrogen-containing polycyclic organic matters are added into the stirring device or the falling film kettle in batches or are added into the falling film kettle at one time, so that the technical problems can be effectively avoided.
Preferably, the top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a cloth template, the bottom of the cloth template is provided with a falling film supporting structure, and the cloth template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device, so that the alcoholysis liquid can be further reacted and homogenized.
Preferably, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
The arrangement can further improve the production efficiency, so that the method is suitable for large-scale industrialized application.
Preferably, the pretreatment step includes, but is not limited to, one or more of crushing, washing, removing mass, drying, and compressing; the post-treatment step includes, but is not limited to, one or more of filtration, washing, crystallization, and drying.
Preferably, the molar ratio of the ester group, the solvent, the metal salt and the nitrogen-containing polycyclic organic matter of the polyester is 1: 2-30: 0.0001 to 0.1:0.0001 to 0.05.
Preferably, the temperature of the stirring device is 150-220 DEG C o C, stirring for 10-120 min; the temperature of the falling film kettle is 150-190 DEG C o And C, the material retention time is 2-60 min.
Compared with the prior art, the invention has the following technical effects:
(1) The invention adopts a falling film kettle flow mode to carry out alcoholysis on polyester, has less power consumption, no dead zone in material flow, easy regulation and control of reaction process and effect, more efficient alcoholysis reaction and more contribution to obtaining high-purity products.
(2) Compared with the existing method for recycling polyester through alcoholysis, the method is simple, uses the dihydric alcohol of one of polyester polymerization monomers as a solvent, adopts the nitrogen-containing polycyclic organic matters and metal salts prepared without the reaction step as a bi-component catalyst, has low catalyst cost, low alcoholysis reaction temperature, short reaction time, high alcoholysis rate, wide raw material applicability, high product purity and easy refining and purification.
Detailed Description
The invention is further described below with reference to examples.
Example 1
Crushing, cleaning, removing impurities, baking, loading in a stirring tank, adding 10 mol of glycol, and heating to 190 deg.f o After C, 0.001 mol of zinc acetate and 0.000 5mol of 1, 8-diazabicyclo [5.4.0 are added]Undec-7-ene, after reacting for 30 min, the reaction solution is pumped into a material chamber of a falling film kettle, and 0.0015 mol of 1, 8-diazabicyclo [5.4.0 ] is injected into the material chamber]Undec-7-ene, and the alcoholysis of polyester molecular chain is completed while the solution falling film flows, and the reaction temperature in the falling film kettle is 175 o And C, discharging the alcoholysis solution after 20min of reaction from the bottom of the falling film kettle, wherein the alcoholysis rate reaches 100%, and filtering, cleaning, crystallizing and drying the alcoholysis solution to obtain an alcoholysis product of the dihydroxyethyl terephthalate BHET with the purity reaching 81%.
The top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device. In addition, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
Example 2
Crushing, cleaning, removing impurities, drying, loading into a stirring tank, adding 8 mol of propylene glycol, and heating to 180 deg.f o After C, adding 0.001 mol of ethylene glycol aluminum, after reacting for 30 min, conveying the reaction liquid into a material chamber of a falling film kettle through a pump, simultaneously injecting 0.003 mol of six-membered bicyclic guanidine into the material chamber, and finishing alcoholysis of polyester molecular chains while carrying out solution falling film flow, wherein the reaction temperature in the falling film kettle is 170 o And C, discharging the alcoholysis solution after 17 min of reaction from the bottom of the falling film kettle, wherein the alcoholysis rate reaches 96%, and filtering, cleaning, crystallizing and drying the alcoholysis solution to obtain an alcoholysis product of the dihydroxypropyl terephthalate BHTT with the purity of 76%.
The top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device. In addition, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
Example 3
Crushing, cleaning, removing impurities, drying, loading into a stirring tank, adding 15 mol of butanediol, and heating to 170 o After C, 0.003 mol of potassium phosphate and 0.001 mol of 1, 4-diazabicyclo [2.2.2]Octane, the reaction is carried out for 30 min, the reaction liquid is conveyed into a falling film reactor material chamber of a falling film reactor by a pump, and 0.005mol of 1, 4-diazabicyclo [2.2.2 ] is injected into the material chamber at the same time]Octane, finishing alcoholysis of polyester molecular chain material while carrying out solution falling film flow, and the reaction temperature in a falling film reactor falling film kettle is 160 o And C, discharging the alcoholysis solution after 16 min of reaction from the bottom of a falling film reactor, wherein the alcoholysis rate reaches 98%, and filtering, cleaning, crystallizing and drying the alcoholysis solution to obtain the alcoholysis product of the dihydroxybutyl terephthalate BHBT with the purity of 80%.
The top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device. In addition, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
Comparative example 1 (with conventional stirred tank reactor)
Crushing, cleaning, removing impurities, baking, loading in a stirring tank, adding 10 mol of glycol, and heating to 190 deg.f o After C, 0.001 mol of zinc acetate and 0.002 mol of 1, 8-diazabicyclo [5.4.0 are added]And (3) after reacting for 50 min, discharging the reaction liquid, wherein the alcoholysis rate is 85%, and filtering, cleaning, crystallizing and drying the alcoholysis liquid to obtain an alcoholysis product of the dihydroxyethyl terephthalate BHET with the purity of 48%.
Comparative example 2 (simultaneous addition of all catalysts in stirred tank at once)
Crushing, cleaning, removing impurities, baking, loading in a stirring tank, adding 10 mol of glycol, and heating to 190 deg.f o After C, 0.001 mol of zinc acetate and 0.002 mol of 1, 8-diazabicyclo [5.4.0 are added]Undec-7-ene, after 30 min of reaction, the reaction solution is pumped into a material chamber of a falling film kettle, and the alcoholysis of polyester molecular chains is completed while the solution flows in a falling film way, and the reaction temperature in the falling film kettle is 175 o And C, discharging the alcoholysis solution after 20min of reaction from the bottom of the falling film kettle, wherein the alcoholysis rate is 90%, and filtering, cleaning, crystallizing and drying the alcoholysis solution to obtain an alcoholysis product of the dihydroxyethyl terephthalate BHET with the purity of 58%.
The top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device. In addition, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
Comparative example 3 (Single use of Metal salt catalyst)
Crushing, cleaning, removing impurities, baking, loading in a stirring tank, adding 10 mol of glycol, and heating to 190 deg.f o C, adding 0.003 mol of zinc acetate, reacting for 30 min, conveying the reaction liquid into a material chamber of a falling film kettle through a pump, and finishing alcoholysis of polyester molecular chains while carrying out falling film flow of the solution, wherein the reaction temperature in the falling film kettle is 175 o And C, discharging the alcoholysis solution after 20min of reaction from the bottom of the falling film kettle, wherein the alcoholysis rate is 68%, and filtering, cleaning, crystallizing and drying the alcoholysis solution to obtain an alcoholysis product of the dihydroxyethyl terephthalate BHET with the purity of 24%.
The top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device. In addition, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
Comparative example 4 (Single use of Nitrogen-containing polycyclic organic catalyst)
Crushing, cleaning, removing impurities, baking, loading in a stirring tank, adding 10 mol of glycol, and heating to 190 deg.f o C, stirring for 30 min, conveying the solution into a falling film kettle material chamber by a pump, and simultaneously injecting 0.002 mol of 1, 8-diazabicyclo [5.4.0 ] into the material chamber]Undec-7-ene, and the alcoholysis of polyester molecular chain is completed while the solution falling film flows, and the reaction temperature in the falling film kettle is 175 o And C, discharging the alcoholysis solution after 20min of reaction from the bottom of the falling film kettle, wherein the alcoholysis rate is 88%, and filtering, cleaning, crystallizing and drying the alcoholysis solution to obtain an alcoholysis product of the dihydroxyethyl terephthalate BHET with the purity of 59%.
The top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes for allowing reaction liquid to flow downwards into the falling film supporting structure; the bottom of the falling film kettle is provided with a stirring transmission device. In addition, the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
As can be seen from the comparison of the data of the examples and the comparative examples, the high-efficiency and rapid alcoholysis of polyester can be realized by adopting a falling film flow mode by using the bi-component catalyst containing the nitrogen-containing polycyclic organic matters and the metal salts, and the purity of the recyclable product can reach a higher level. The traditional method of stirring kettle alcoholysis (comparative example 1) has low alcoholysis rate and low product purity; the mode of simultaneously adding two catalysts into the stirring kettle and then carrying out falling film flow-out alcoholysis (comparative example 2) is adopted, and the alcoholysis effect is also obviously lower than that of adding the catalysts into the falling film kettle. Further, the metal salt single component catalyst (comparative example 3) and the nitrogen-containing heterocyclic compound single component catalyst (comparative example 4) were low in alcoholysis rate and low in BHET yield. The results show that the implementation effect obtained by the invention cannot be achieved by adopting a single-component catalyst, a double-component catalyst which is not specially processed and a traditional flow mode.
The foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and any simple modification, variation and equivalent transformation of the above embodiment according to the technical substance of the present invention still fall within the scope of the technical solution of the present invention.
Claims (10)
1. A method of falling film flow alcoholysis of a polyester, characterized by: adding pretreated polyester waste and solvent into a stirring device, adding a part of catalyst after reaching a set temperature, conveying the obtained reaction liquid into a falling film kettle for reaction, carrying out falling film flow on the reaction liquid, and further alcoholysis of polyester, discharging the alcoholysis liquid obtained after the reaction from a discharge port at the bottom of the falling film kettle, and carrying out post-treatment to obtain a high-purity recyclable polyester reaction raw material;
the catalyst is a bi-component catalyst and comprises metal salt and nitrogen-containing polycyclic organic matter; wherein: the nitrogen-containing polycyclic organic matter is selected from one or more of cycloalkanes and cycloalkenes with two nitrogen elements and a ring number of 2 or 3; the metal salt is selected from one or more of metal alkoxides, metal carboxylates and metal phosphates of potassium, zinc, aluminum and titanium;
the top of the falling film kettle is provided with a material chamber, a bottom plate of the material chamber is a distribution template, the bottom of the distribution template is provided with a falling film supporting structure, and the distribution template is provided with holes which can enable reaction liquid to flow into the falling film supporting structure downwards.
2. The method of claim 1, wherein: the polyester waste is any one or more of waste polyester plastics, bottle flakes, films, fibers, fabrics, melt discharge materials, pipes and sheets with the molecular weight exceeding 10000 and an ester group structure on a molecular main chain.
3. The method of claim 1, wherein: the solvent is a glycol compound.
4. The method of claim 1, wherein: the metal salt is added in a stirring device; the nitrogen-containing polycyclic organic matters are added into the stirring device and the falling film kettle respectively in two batches or added into the falling film kettle at one time.
5. The method of claim 1, wherein: the nitrogen-containing polycyclic organic matter is one or more selected from six-membered bicyclic guanidine, diazabicycloalkane and diazabicycloalkane compounds;
the metal salt is selected from one of metal carboxylates of potassium and zinc.
6. The method of claim 1, wherein: and a stirring transmission device is arranged at the bottom of the falling film kettle.
7. The method of claim 1, wherein: the falling film kettle is provided with a jacket structure, and the jacket structure is provided with a heat preservation system, a heat medium inflow port and a heat medium outflow port.
8. The method of claim 1, wherein: the pretreatment step comprises one or more of crushing, cleaning, quality-removing, drying and compressing; the post-treatment step includes one or more of filtration, washing, crystallization, and drying.
9. The method of claim 1, wherein: the molar ratio of the ester group, the solvent, the metal salt and the nitrogen-containing polycyclic organic matter of the polyester is 1: 2-30: 0.0001 to 0.1:0.0001 to 0.05.
10. The method of claim 1, wherein: the temperature of the stirring device is 150-220 DEG C o C, stirring for 10-120 min; the temperature of the falling film kettle is 150-190 DEG C o And C, the material retention time is 2-60 min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210626557.0A CN114890892B (en) | 2022-06-04 | 2022-06-04 | Method for degrading polyester through film-falling flow alcoholysis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210626557.0A CN114890892B (en) | 2022-06-04 | 2022-06-04 | Method for degrading polyester through film-falling flow alcoholysis |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114890892A CN114890892A (en) | 2022-08-12 |
| CN114890892B true CN114890892B (en) | 2023-09-15 |
Family
ID=82725477
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210626557.0A Active CN114890892B (en) | 2022-06-04 | 2022-06-04 | Method for degrading polyester through film-falling flow alcoholysis |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114890892B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1780898A (en) * | 2003-04-30 | 2006-05-31 | 昭和电工株式会社 | Organic polymer light-emitting element material having gold complex structure and organic polymer light-emitting element |
| CN103435728A (en) * | 2013-09-10 | 2013-12-11 | 浙江大学 | Preparation method of porous polyquaternary phosphorus ionic liquid |
| CN103930395A (en) * | 2011-03-04 | 2014-07-16 | 国际商业机器公司 | Methods of depolymerizing terephthalate polyesters |
| CN107442059A (en) * | 2017-08-08 | 2017-12-08 | 浙江理工大学 | A kind of falling liquid film melt polycondensation reaction device |
| CN108003380A (en) * | 2017-12-21 | 2018-05-08 | 福建荔枝新材料有限公司 | A kind of polyester material recycles and utilizes ultrasound to carry out surface treatment method |
| CN113117748A (en) * | 2021-04-25 | 2021-07-16 | 南京大学 | Bicyclic guanidine salt eutectic solvent catalyst and preparation method and application thereof |
| WO2022112715A1 (en) * | 2020-11-24 | 2022-06-02 | Recyc'elit | Improved method for recycling pet by alcoholysis |
-
2022
- 2022-06-04 CN CN202210626557.0A patent/CN114890892B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1780898A (en) * | 2003-04-30 | 2006-05-31 | 昭和电工株式会社 | Organic polymer light-emitting element material having gold complex structure and organic polymer light-emitting element |
| CN103930395A (en) * | 2011-03-04 | 2014-07-16 | 国际商业机器公司 | Methods of depolymerizing terephthalate polyesters |
| CN103435728A (en) * | 2013-09-10 | 2013-12-11 | 浙江大学 | Preparation method of porous polyquaternary phosphorus ionic liquid |
| CN107442059A (en) * | 2017-08-08 | 2017-12-08 | 浙江理工大学 | A kind of falling liquid film melt polycondensation reaction device |
| CN108003380A (en) * | 2017-12-21 | 2018-05-08 | 福建荔枝新材料有限公司 | A kind of polyester material recycles and utilizes ultrasound to carry out surface treatment method |
| WO2022112715A1 (en) * | 2020-11-24 | 2022-06-02 | Recyc'elit | Improved method for recycling pet by alcoholysis |
| CN113117748A (en) * | 2021-04-25 | 2021-07-16 | 南京大学 | Bicyclic guanidine salt eutectic solvent catalyst and preparation method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114890892A (en) | 2022-08-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7071528B2 (en) | How to collect waste polyester material | |
| US11572452B2 (en) | Method for recycling continuous alcoholysis of waste polyester material | |
| US11655351B2 (en) | Method for recycling waste polyester with continuous alcoholysis and transesterification | |
| CN106832397B (en) | The method of online reuse PET Polymerization Waste | |
| CN112679464A (en) | Method for preparing lactide with high yield | |
| CN102701985A (en) | Method for preparing epoxy resin curing agent by performing alcoholysis on PET (Polyethylene Terephthalate) polyester | |
| CN114656684A (en) | Method for preparing high-purity recycled PET (polyethylene terephthalate) polyester by using waste PET polyester | |
| CN112851502A (en) | Method for catalyzing waste PET polyester to carry out methanol alcoholysis by using choline and terephthalic acid non-metallic ionic liquid | |
| CN114437328A (en) | Method for preparing PET slices from waste PET materials and product | |
| CN114890892B (en) | Method for degrading polyester through film-falling flow alcoholysis | |
| CN104603177A (en) | Gas scrubber and related processes | |
| CN113387920A (en) | Continuous production method and device from lactic acid oligomer to high optical purity polymer grade lactide | |
| JP4330918B2 (en) | How to recycle polyester waste | |
| CN114890898B (en) | Method for recycling waste polyester based on alcoholysis of two-component catalyst | |
| CN113087885B (en) | Production method of recycled polyester chips | |
| CN101434539B (en) | Preparation of benzyl acetate | |
| CN115141363A (en) | Method for preparing regenerated cationic polyester by using waste polyester | |
| CN1304359C (en) | Process for synthesizing propylene glycol monomethyl ether acetate (PMA) | |
| CN111138697A (en) | Method for preparing PET (polyethylene terephthalate) film by using waste PET material | |
| JP2004231855A (en) | Method for producing polyethylene terephthalate | |
| CN115558090B (en) | Preparation method of polybutylene succinate with low tetrahydrofuran content | |
| CN116283566A (en) | Method for recycling waste PET polyester by alcoholysis with ionic liquid as catalyst | |
| CN111574558B (en) | Preparation method for producing tributyl phosphate by using microchannel technology | |
| CN110964190B (en) | Raw material conveying and blending device used in polycarbonate synthesis process | |
| CN110951063B (en) | Catalyst composition for preparing polyester and preparation method of polyester |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20230317 Address after: 310018 Zhejiang University of technology, No. 928, No. 2 street, Qiantang District, Hangzhou, Zhejiang Province Applicant after: ZHEJIANG SCI-TECH University Applicant after: Jiangsu solide New Material Group Co.,Ltd. Address before: 310018 Zhejiang University of technology, No. 928, No. 2 street, Qiantang District, Hangzhou, Zhejiang Province Applicant before: ZHEJIANG SCI-TECH University |
|
| TA01 | Transfer of patent application right | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |