CN118080004A - Efficient catalyst for preparing polylactic acid - Google Patents
Efficient catalyst for preparing polylactic acid Download PDFInfo
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- CN118080004A CN118080004A CN202211500789.8A CN202211500789A CN118080004A CN 118080004 A CN118080004 A CN 118080004A CN 202211500789 A CN202211500789 A CN 202211500789A CN 118080004 A CN118080004 A CN 118080004A
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- molecular sieve
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- 239000003054 catalyst Substances 0.000 title claims abstract description 41
- 229920000747 poly(lactic acid) Polymers 0.000 title claims abstract description 22
- 239000004626 polylactic acid Substances 0.000 title claims abstract description 22
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 claims abstract description 38
- 239000002808 molecular sieve Substances 0.000 claims abstract description 26
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000000034 method Methods 0.000 claims abstract description 21
- 238000006243 chemical reaction Methods 0.000 claims abstract description 19
- 239000004310 lactic acid Substances 0.000 claims abstract description 19
- 235000014655 lactic acid Nutrition 0.000 claims abstract description 19
- 229910021645 metal ion Inorganic materials 0.000 claims abstract description 15
- KWIUHFFTVRNATP-UHFFFAOYSA-N Betaine Natural products C[N+](C)(C)CC([O-])=O KWIUHFFTVRNATP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000002253 acid Substances 0.000 claims abstract description 10
- 229960003237 betaine Drugs 0.000 claims abstract description 6
- 238000006317 isomerization reaction Methods 0.000 claims abstract description 6
- 239000011159 matrix material Substances 0.000 claims abstract description 6
- 238000007385 chemical modification Methods 0.000 claims abstract description 5
- HDGGAKOVUDZYES-UHFFFAOYSA-K erbium(iii) chloride Chemical compound Cl[Er](Cl)Cl HDGGAKOVUDZYES-UHFFFAOYSA-K 0.000 claims abstract description 5
- KWIUHFFTVRNATP-UHFFFAOYSA-O N,N,N-trimethylglycinium Chemical compound C[N+](C)(C)CC(O)=O KWIUHFFTVRNATP-UHFFFAOYSA-O 0.000 claims abstract 3
- 238000007151 ring opening polymerisation reaction Methods 0.000 claims description 13
- 239000002994 raw material Substances 0.000 claims description 10
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims description 6
- ROSDSFDQCJNGOL-UHFFFAOYSA-N Dimethylamine Chemical compound CNC ROSDSFDQCJNGOL-UHFFFAOYSA-N 0.000 claims description 6
- 239000003607 modifier Substances 0.000 claims description 5
- 229910052691 Erbium Inorganic materials 0.000 claims description 4
- UYAHIZSMUZPPFV-UHFFFAOYSA-N erbium Chemical compound [Er] UYAHIZSMUZPPFV-UHFFFAOYSA-N 0.000 claims description 4
- FSSPGSAQUIYDCN-UHFFFAOYSA-N 1,3-Propane sultone Chemical compound O=S1(=O)CCCO1 FSSPGSAQUIYDCN-UHFFFAOYSA-N 0.000 claims description 3
- QEJPOEGPNIVDMK-UHFFFAOYSA-N 3-bromo-2,2-bis(bromomethyl)propan-1-ol Chemical compound OCC(CBr)(CBr)CBr QEJPOEGPNIVDMK-UHFFFAOYSA-N 0.000 claims description 3
- 229910021536 Zeolite Inorganic materials 0.000 claims description 3
- 238000005882 aldol condensation reaction Methods 0.000 claims description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims description 3
- 239000010457 zeolite Substances 0.000 claims description 3
- 230000018044 dehydration Effects 0.000 claims description 2
- 238000006297 dehydration reaction Methods 0.000 claims description 2
- 230000036571 hydration Effects 0.000 claims description 2
- 238000006703 hydration reaction Methods 0.000 claims description 2
- 230000007062 hydrolysis Effects 0.000 claims description 2
- 238000006460 hydrolysis reaction Methods 0.000 claims description 2
- 238000006462 rearrangement reaction Methods 0.000 claims description 2
- 238000007792 addition Methods 0.000 claims 1
- 239000001913 cellulose Substances 0.000 abstract description 8
- 229920002678 cellulose Polymers 0.000 abstract description 8
- 239000002028 Biomass Substances 0.000 abstract description 6
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 abstract description 4
- 239000008103 glucose Substances 0.000 abstract description 4
- 230000008569 process Effects 0.000 abstract description 4
- RFSUNEUAIZKAJO-ARQDHWQXSA-N Fructose Chemical compound OC[C@H]1O[C@](O)(CO)[C@@H](O)[C@@H]1O RFSUNEUAIZKAJO-ARQDHWQXSA-N 0.000 abstract description 3
- 229930091371 Fructose Natural products 0.000 abstract description 3
- 239000005715 Fructose Substances 0.000 abstract description 3
- 238000005575 aldol reaction Methods 0.000 abstract description 3
- JVTAAEKCZFNVCJ-REOHCLBHSA-N L-lactic acid Chemical compound C[C@H](O)C(O)=O JVTAAEKCZFNVCJ-REOHCLBHSA-N 0.000 description 8
- 230000003197 catalytic effect Effects 0.000 description 7
- 238000002360 preparation method Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- 229920001432 poly(L-lactide) Polymers 0.000 description 5
- KSBAEPSJVUENNK-UHFFFAOYSA-L tin(ii) 2-ethylhexanoate Chemical compound [Sn+2].CCCCC(CC)C([O-])=O.CCCCC(CC)C([O-])=O KSBAEPSJVUENNK-UHFFFAOYSA-L 0.000 description 5
- JJTUDXZGHPGLLC-UHFFFAOYSA-N lactide Chemical group CC1OC(=O)C(C)OC1=O JJTUDXZGHPGLLC-UHFFFAOYSA-N 0.000 description 4
- 238000006068 polycondensation reaction Methods 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- JJTUDXZGHPGLLC-IMJSIDKUSA-N 4511-42-6 Chemical compound C[C@@H]1OC(=O)[C@H](C)OC1=O JJTUDXZGHPGLLC-IMJSIDKUSA-N 0.000 description 3
- 239000002841 Lewis acid Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 150000007517 lewis acids Chemical class 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 238000012662 bulk polymerization Methods 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 150000001720 carbohydrates Chemical class 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011968 lewis acid catalyst Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 230000002194 synthesizing effect Effects 0.000 description 2
- WYTZZXDRDKSJID-UHFFFAOYSA-N (3-aminopropyl)triethoxysilane Chemical compound CCO[Si](OCC)(OCC)CCCN WYTZZXDRDKSJID-UHFFFAOYSA-N 0.000 description 1
- FALRKNHUBBKYCC-UHFFFAOYSA-N 2-(chloromethyl)pyridine-3-carbonitrile Chemical compound ClCC1=NC=CC=C1C#N FALRKNHUBBKYCC-UHFFFAOYSA-N 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- -1 alkali metal alkoxide Chemical class 0.000 description 1
- 230000002152 alkylating effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 239000002638 heterogeneous catalyst Substances 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229940014800 succinic anhydride Drugs 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Catalysts (AREA)
Abstract
The invention discloses a high-efficiency catalyst for preparing polylactic acid, which is prepared by grafting claw-shaped betaine head trisulfonic acid onto the surface of a metal ion doped nano Sn-beta molecular sieve serving as a matrix through a chemical modification reaction and treating the surface of the catalyst by erbium trichloride. The catalyst has the functions of efficiently catalyzing glucose isomerization reaction and fructose retro-aldol reaction, greatly improves the yield of the process of converting cellulose into lactic acid, and provides a new way for efficiently catalyzing and converting biomass resources into lactic acid.
Description
Technical Field
The invention belongs to the technical field of new materials, and relates to a high-efficiency catalyst for preparing polylactic acid.
Background
The method for chemically synthesizing the polylactic acid by taking the lactic acid as the raw material comprises a direct polycondensation method and a lactide ring-opening polymerization method, and compared with the direct polycondensation method, the ring-opening polymerization method has the advantages of less reaction byproducts, simple polymerization equipment and high molecular weight of the polylactic acid, and is a main method for large-scale industrialized production of the polylactic acid.
However, the method still has the defects of long synthetic route, complex process, high cost and the like, and influences the popularization and application of polylactic acid products. Wherein, the catalyst of ring-opening polymerization plays a key role in preparing polylactic acid with high relative molecular mass and reducing production cost. At present, the catalyst for ring-opening polymerization comprises protonic acid, lewis acid, alkylating reagent, alkali metal alkoxide, organic compound of transition metal, oxide and the like, wherein stannous octoate is a catalyst with better effect which is recognized at present, and the catalyst has the characteristics of high activity, small catalyst consumption, high relative molecular mass of the prepared polymer and the like, and becomes one of hot spots for researching a lactide ring-opening polymerization catalytic system. For example, the ring-opening polymerization of L-lactide was successfully carried out at the university of Donghua with stannous octoate as a catalyst and supercritical carbon dioxide as a solvent. The L-lactic acid is subjected to high-temperature catalytic reaction to obtain oligomeric (L-lactic acid) by the national academy of sciences of China's application chemistry institute, then is subjected to high-temperature pyrolysis and reduced pressure distillation to obtain monomer L-lactide (LLA), and is subjected to ring-opening polymerization by taking stannous octoate as a catalyst to obtain poly (L-lactic acid) PLLA, wherein the relative molecular mass of the PLLA can reach 40 ten thousand. The PLLA is prepared by lactide bulk polymerization by taking stannous octoate as a catalyst at the university of Zhongshan, when the molar ratio of the monomer to the catalyst is 8000:1, the reaction temperature is 130 ℃ and the reaction time is 48 hours, and the weight average molecular weight of the PLLA is up to 198 ten thousand.
Although stannous octoate coordination insertion ring-opening polymerization is utilized to prepare polylactic acid with high relative molecular mass, the reaction is only suitable for a high-temperature bulk polymerization system, the conversion rate is low, and the industrial production and popularization of high-performance polylactic acid are severely restricted.
Disclosure of Invention
The invention aims to overcome the defects and provide the efficient catalyst for preparing the polylactic acid, which is a novel heterogeneous catalyst capable of simultaneously and efficiently catalyzing glucose isomerization and fructose retro-aldol reaction, namely the organic sulfonic acid erbium-modified nano Sn-beta molecular sieve catalyst, by loading Lewis acid with a similar structure of Er (OTf) 3 onto the Sn-beta molecular sieve by a chemical modification method, so that a novel path is provided for efficiently catalyzing and converting biomass resources into lactic acid. The homogeneous Lewis acid catalyst has a special catalytic effect on the conversion of saccharides into lactic acid.
The object of the invention is achieved by:
The catalyst is prepared by taking a metal ion doped nano Sn-beta molecular sieve as a matrix, grafting claw-shaped betaine head trisulfonic acid onto the surface of the catalyst through a chemical modification reaction, and treating the catalyst by erbium trichloride.
Further, the claw-shaped betaine head group trisulfonic acid modifier is prepared from tribromoneopentyl alcohol, dimethylamine and 1, 3-propane sultone serving as raw materials.
Further, the metal ion doped nano Sn-beta molecular sieve is prepared by taking nano beta molecular sieve as raw material, dealuminating, doping Sn 4+ to prepare Sn-beta zeolite molecular sieve, and then carrying out exchange reaction with metal ion to prepare the metal ion doped nano Sn-beta molecular sieve.
The method for preparing the polylactic acid by using the high-efficiency catalyst comprises the steps of taking lignocellulose as a raw material, adding the catalyst after pretreatment, preparing lactic acid by hydrolysis, isomerization, reverse aldol condensation, dehydration and hydration rearrangement reaction, and preparing the polylactic acid by ring-opening polymerization of the lactic acid. The method for chemically synthesizing the polylactic acid by taking the lactic acid as the raw material comprises a direct polycondensation method and a lactide ring-opening polymerization method, and compared with the direct polycondensation method, the ring-opening polymerization method has the advantages of less reaction byproducts, simple polymerization equipment and high molecular weight of the polylactic acid, and is a main method for large-scale industrialized production of the polylactic acid.
According to the invention, a metal ion doped nano Sn-beta molecular sieve is used as a matrix, claw-shaped betaine head trisulfonic acid is grafted onto the surface of the matrix through a chemical modification reaction, and the organic sulfonic acid erbium modified nano Sn-beta molecular sieve catalyst is prepared through erbium trichloride treatment. The catalyst is applied to catalytic conversion of cellulose into lactic acid, can effectively catalyze the catalytic process of converting cellulose into lactic acid with high selectivity, and is applied to catalytic conversion of cellulose to prepare polylactic acid for production. The catalyst plays a key role in efficiently converting cellulose into lactic acid.
The matrix of the catalyst is a metal ion doped nano Sn-beta molecular sieve, and has excellent catalytic effect on glucose isomerization reaction; the modified part is Lewis acid with a structure similar to Er (OTf) 3, and can catalyze the aldol condensation reaction with high selectivity. Therefore, the catalyst has the functions of efficiently catalyzing glucose isomerization reaction and fructose retro-aldol reaction, greatly improves the yield of the process of converting cellulose into lactic acid, and provides a new way for efficiently catalyzing and converting biomass resources into lactic acid.
Compared with the prior art, the invention has the beneficial effects that:
The development of the catalyst breaks monopoly of foreign enterprises on biomass-based resource catalytic conversion technology, realizes autonomous development of biomass resource renewable utilization technology, improves the production level of biodegradable material enterprises in China, improves the performance and quality of products, and solves the problem of large-scale production of converting biomass carbohydrate into lactic acid.
Drawings
FIG. 1 is a flow chart of a preparation process of the erbium-modified nano Sn-beta molecular sieve catalyst.
Detailed Description
The invention is further illustrated by the following examples:
example 1 preparation of catalyst
(1) Synthesis of claw-shaped betaine head trisulfonic acid modifier
The preparation method comprises the steps of taking tribromoneopentyl alcohol and dimethylamine as raw materials, reacting a synthesis intermediate 1,1 with a sulfonating agent 1, 3-propane sultone to generate a synthesis intermediate 2, and carrying out esterification reaction on succinic anhydride to obtain the target compound claw-shaped betaine head trisulfonic acid modifier.
(2) Preparation of metal ion doped nano Sn-beta molecular sieve
The nano-beta molecular sieve is used as a raw material, is subjected to dealumination treatment and Sn 4+ doping to prepare the Sn-beta zeolite molecular sieve, and then is subjected to exchange reaction with metal ions to prepare the metal ion doped nano-Sn-beta molecular sieve.
(3) Preparation of organic sulfonic acid erbium modified nano Sn-beta molecular sieve catalyst
And (3) carrying out solid-phase grafting reaction on the prepared claw-shaped betaine head group trisulfonic acid modifier, the metal ion doped nano Sn-beta molecular sieve and gamma-aminopropyl triethoxysilane by using a high-energy ball mill, and treating the obtained product by erbium trichloride to prepare the organic sulfonic acid erbium modified nano Sn-beta molecular sieve catalyst.
Example 2 preparation of polylactic acid
The lactic acid is prepared by taking cellulose as a raw material, using the organic sulfonic acid erbium-modified nano Sn-beta molecular sieve prepared in the embodiment 1 as a heterogeneous Lewis acid catalyst, and hydrolyzing lignocellulose. The weight ratio of lignocellulose to the catalyst is 2:1, the reaction temperature is 240 ℃, the pressure of N 2 is 2.0MPa, and the reaction time is 30min. And preparing polylactic acid by ring-opening polymerization of the lactic acid intermediate.
The performance test data of the polylactic acid product prepared according to the method of example 2 are shown in Table 1:
TABLE 1 comparison of key technical indicators for conversion of cellulose to lactic acid
Claims (4)
1. The catalyst is characterized in that a metal ion doped nano Sn-beta molecular sieve is used as a matrix, claw-shaped betaine head trisulfonic acid is grafted onto the surface of the catalyst through a chemical modification reaction, and the catalyst is subjected to erbium trichloride treatment to prepare the organic sulfonic acid erbium modified nano Sn-beta molecular sieve catalyst.
2. The catalyst according to claim 1, wherein the claw-shaped betaine head group trisulfonic acid modifier is prepared from tribromoneopentyl alcohol, dimethylamine and 1, 3-propane sultone.
3. The catalyst of claim 1, wherein the metal ion doped nano Sn-beta molecular sieve is prepared by dealuminating nano beta molecular sieve as raw material, doping Sn 4+ to prepare Sn-beta zeolite molecular sieve, and then carrying out exchange reaction with metal ion to prepare metal ion doped nano Sn-beta molecular sieve.
4. A method for preparing polylactic acid by using the high-efficiency catalyst as claimed in claim 1, which is characterized in that lignocellulose is used as a raw material, and lactic acid is prepared by pretreatment, catalyst addition, hydrolysis, isomerization, reverse aldol condensation, dehydration and hydration rearrangement reaction, and then ring-opening polymerization of lactic acid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211500789.8A CN118080004A (en) | 2022-11-28 | 2022-11-28 | Efficient catalyst for preparing polylactic acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211500789.8A CN118080004A (en) | 2022-11-28 | 2022-11-28 | Efficient catalyst for preparing polylactic acid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118080004A true CN118080004A (en) | 2024-05-28 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211500789.8A Pending CN118080004A (en) | 2022-11-28 | 2022-11-28 | Efficient catalyst for preparing polylactic acid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118080004A (en) |
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2022
- 2022-11-28 CN CN202211500789.8A patent/CN118080004A/en active Pending
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