CN116854589A - Dimethyl succinate preparation method based on azeotropic circulation - Google Patents
Dimethyl succinate preparation method based on azeotropic circulation Download PDFInfo
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- CN116854589A CN116854589A CN202310835711.XA CN202310835711A CN116854589A CN 116854589 A CN116854589 A CN 116854589A CN 202310835711 A CN202310835711 A CN 202310835711A CN 116854589 A CN116854589 A CN 116854589A
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- dimethyl succinate
- reaction
- methanol
- azeotropic
- water
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- MUXOBHXGJLMRAB-UHFFFAOYSA-N Dimethyl succinate Chemical compound COC(=O)CCC(=O)OC MUXOBHXGJLMRAB-UHFFFAOYSA-N 0.000 title claims abstract description 28
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 99
- 238000006243 chemical reaction Methods 0.000 claims abstract description 54
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 41
- 238000000034 method Methods 0.000 claims abstract description 38
- 239000002904 solvent Substances 0.000 claims abstract description 30
- 238000010992 reflux Methods 0.000 claims abstract description 16
- 238000004519 manufacturing process Methods 0.000 claims abstract description 15
- FALRKNHUBBKYCC-UHFFFAOYSA-N 2-(chloromethyl)pyridine-3-carbonitrile Chemical compound ClCC1=NC=CC=C1C#N FALRKNHUBBKYCC-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229940014800 succinic anhydride Drugs 0.000 claims abstract description 14
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Natural products C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000002253 acid Substances 0.000 claims abstract description 4
- 238000011084 recovery Methods 0.000 claims abstract description 4
- 239000011347 resin Substances 0.000 claims abstract description 4
- 229920005989 resin Polymers 0.000 claims abstract description 4
- 238000005886 esterification reaction Methods 0.000 claims description 21
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 14
- 239000003208 petroleum Substances 0.000 claims description 7
- 239000012808 vapor phase Substances 0.000 claims description 7
- 239000012043 crude product Substances 0.000 claims description 6
- 239000003054 catalyst Substances 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 claims description 4
- 239000007864 aqueous solution Substances 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 239000000243 solution Substances 0.000 claims description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 3
- 239000007791 liquid phase Substances 0.000 claims description 3
- 239000011259 mixed solution Substances 0.000 claims description 3
- 125000002091 cationic group Chemical group 0.000 claims description 2
- 239000011148 porous material Substances 0.000 claims description 2
- 239000002994 raw material Substances 0.000 abstract description 11
- 238000000926 separation method Methods 0.000 abstract description 6
- 238000009776 industrial production Methods 0.000 abstract description 4
- 230000035484 reaction time Effects 0.000 abstract description 4
- 238000005265 energy consumption Methods 0.000 abstract description 3
- 238000006555 catalytic reaction Methods 0.000 abstract description 2
- KDYFGRWQOYBRFD-UHFFFAOYSA-N succinic acid Chemical compound OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 16
- 239000001384 succinic acid Substances 0.000 description 8
- FPYJFEHAWHCUMM-UHFFFAOYSA-N maleic anhydride Chemical compound O=C1OC(=O)C=C1 FPYJFEHAWHCUMM-UHFFFAOYSA-N 0.000 description 7
- 230000032050 esterification Effects 0.000 description 6
- 238000005984 hydrogenation reaction Methods 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 230000007547 defect Effects 0.000 description 3
- LDCRTTXIJACKKU-ARJAWSKDSA-N dimethyl maleate Chemical compound COC(=O)\C=C/C(=O)OC LDCRTTXIJACKKU-ARJAWSKDSA-N 0.000 description 3
- 238000010924 continuous production Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 239000003377 acid catalyst Substances 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 239000003899 bactericide agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- VAYGXNSJCAHWJZ-UHFFFAOYSA-N dimethyl sulfate Chemical compound COS(=O)(=O)OC VAYGXNSJCAHWJZ-UHFFFAOYSA-N 0.000 description 1
- 239000002778 food additive Substances 0.000 description 1
- 235000013373 food additive Nutrition 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000011964 heteropoly acid Substances 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 239000004611 light stabiliser Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 235000013599 spices Nutrition 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000007039 two-step reaction Methods 0.000 description 1
- 238000011514 vinification Methods 0.000 description 1
- -1 wine making Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/56—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D307/60—Two oxygen atoms, e.g. succinic anhydride
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a preparation method of dimethyl succinate based on azeotropic circulation, which comprises the steps of carrying out initial reaction by taking succinic anhydride and methanol as raw materials under the catalysis of strong acid type large-aperture styrene cationic resin, then carrying out water and methanol recovery operation by a reflux to obtain crude dimethyl succinate, and finally purifying to obtain high-content dimethyl succinate. Compared with the traditional process, the method can reduce the generation of nearly half of reaction water, thereby reducing the separation energy consumption; by utilizing the azeotropic characteristic of water and heterogeneous solvent, the reaction water is continuously brought out from the reaction system, the forward progress of the reaction is promoted, the reaction efficiency is improved, the reaction time is greatly shortened, the complicated intermediate treatment process in the traditional process is reduced, the method is used for industrial production, and has strong operability, high operation elasticity and higher product yield. The raw materials and the solvent are recycled, so that near zero emission is realized to the greatest extent, and the aim of clean production is fulfilled.
Description
Technical Field
The invention relates to the technical field of chemical industry, in particular to a dimethyl succinate preparation method based on azeotropic circulation.
Background
Dimethyl succinate is a very important downstream maleic anhydride product, and is widely applied to aspects such as light stabilizer 622 and 783, high-grade paint, bactericide, medical intermediate, organic solvent, food additive, wine making, essence and spice processing, gas chromatography fixing liquid and the like, and along with continuous updating of technology, the application in the field of degradable new materials in the future is more and more extensive.
At present, the technology of dimethyl succinate mainly comprises two processes of a succinic acid esterification method and a maleic anhydride esterification hydrogenation method, and the succinic acid esterification method is mainly adopted in industrial production, succinic acid and methanol are used as raw materials, and the dimethyl succinate is obtained through esterification reaction under the catalysis of an acid catalyst. For example, the patent application number is 2021107621686, and the patent name is a preparation method and equipment of dimethyl succinate.
The succinic acid esterification method uses succinic acid and methanol as raw materials, and uses concentrated sulfuric acid or heteropolyacid as a catalyst to carry out esterification reaction, and the process has the advantages of more side reactions, low yield, complex post-treatment and serious equipment corrosion, and the byproduct of highly toxic dimethyl sulfate seriously pollutes the environment. In addition, the esterification reaction speed of the succinic acid esterification method is low, and the reaction is difficult to thoroughly process due to the large amount of generated reaction water, so that the purification difficulty of the product is high;
the maleic anhydride esterification hydrogenation method takes maleic anhydride and methanol as raw materials to carry out two-step reaction to obtain dimethyl maleate, and then the dimethyl maleate is subjected to electrochemical hydrogenation reduction reaction to obtain dimethyl succinate. The method uses maleic anhydride as the initial raw material, greatly reduces the production cost and has faster reaction rate. However, the reaction needs 16 steps of reaction and separation, the whole process is complicated, and the electrochemical hydrogenation reduction method of the dimethyl maleate has the defects of serious electrode corrosion, low current efficiency and raw material conversion rate, difficult maintenance of an electrolytic tank, large investment, large occupied area, unfavorable mass production and the like.
Disclosure of Invention
The invention aims to solve the problems and provide the dimethyl succinate preparation method based on azeotropic circulation, which can generate nearly half of reaction water, improve the reaction efficiency, greatly shorten the reaction time and reduce the complicated intermediate treatment process in the traditional process.
The invention realizes the above purpose through the following technical scheme:
the preparation method of dimethyl succinate based on azeotropic circulation comprises the following steps:
s1, initial reaction:
adding succinic anhydride, a catalyst, a heterogeneous solvent and dehydrated absolute methanol into an esterification reaction kettle with a condenser according to a set proportion, heating, and then heating to a set temperature, and starting total reflux until the moisture content in the esterification reaction kettle reaches a set threshold;
s2, refluxing with water:
stopping total reflux, switching the liquid phase of the condenser to a water separator, and quantitatively refluxing the heterogeneous solvent into the esterification reaction kettle by using the upper solution of the water separator as the heterogeneous solvent, so as to keep the water content of the water content tester of the vapor phase pipe at the top of the esterification reaction kettle between set thresholds;
s3, recovering methanol:
feeding the mixed solution of the lower layer of the water knockout drum and the aqueous solution containing methanol into a methanol recovery tower for rectification, allowing 99.8% methanol to flow out from the top of the tower, performing deep water removal through a 3A molecular sieve, and performing submerged continuous supplementary feeding to an esterification reaction kettle;
s4, terminating the reaction:
when the water content of the online moisture tester of the vapor phase pipe at the top of the reactor is lower than 1.5-5%, stopping the reflux of the heterogeneous solvent to the reaction kettle, stopping the supplementary feeding of the anhydrous methanol, distilling and extracting the solvent in the reaction kettle, obtaining a crude product of dimethyl succinate with the content of more than or equal to 93%, and purifying the crude product to obtain the dimethyl succinate with the content of more than or equal to 99.3%.
Preferably, the catalyst in the step S1 is a strong acid type large pore size styrene type cationic resin; the temperature is set to be 75-95 ℃ in the step S1; the moisture content in the step S1 is set to 7-10 percent.
Preferably, the heterogeneous solvent in the step S1 is a mixture of cyclohexane and petroleum ether in a proportion of 60-70%, and the petroleum ether is added in a proportion of 30-40%.
Preferably, the continuous supplementary feeding of methanol in the step S3 is a submerged feeding, and the feeding amount of methanol is 4-15KG/h.
Preferably, in the step S1, the mass ratio of succinic anhydride to anhydrous methanol is 1:1.2-1.4.
Preferably, the addition amount of the heterogeneous solvent is 1.5-2 times of the addition amount of the succinic anhydride.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention can reduce the generation of nearly half of reaction water, thereby reducing the separation energy consumption; by utilizing the azeotropic characteristic of water and heterogeneous solvent, the reaction water is continuously brought out of the reaction system, the forward progress of the reaction is promoted, the reaction efficiency is improved, the reaction time is greatly shortened, the complicated intermediate treatment process in the traditional process is reduced, the method is used for industrial production, the operability is strong, the operation elasticity is high, and the product yield is higher; the raw materials and the solvent are recycled, so that near zero emission is realized to the greatest extent, and the aim of clean production is fulfilled;
2. the invention has high overall process flexibility, can realize linkage co-production with a device for producing succinic anhydride by maleic anhydride hydrogenation, and has high operational flexibility;
3. the raw material of the invention is succinic anhydride, which avoids the defects of high equipment requirement, large environmental pollution, slow reaction and the like in the synthesis of succinic acid into dimethyl succinate;
4. the production process can realize continuous production, has strong operability and high stability, and the prepared product has high purity and good quality, and has rapid preparation reaction, thereby being convenient for realizing large-scale industrialization;
5. in the production process, the azeotropic characteristic of the heterogeneous solvent and water is fully utilized, the reaction water in the reaction system is effectively removed, the forward progress of the reaction is quickened, the separation process is simplified, the conversion rate of the reaction is improved, the production cost is reduced, and the reaction is more thoroughly carried out by adopting the azeotropic circulation process method.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions of the prior art, the drawings that are necessary for the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention and that other drawings can be obtained according to these drawings without inventive faculty for a person skilled in the art.
Fig. 1 is a process flow diagram of the present invention.
Detailed Description
The technical scheme of the invention is further explained with reference to the accompanying figure 1:
as shown in fig. 1, the invention discloses a dimethyl succinate preparation method based on azeotropic circulation, which comprises the following steps:
s1, initial reaction:
adding succinic anhydride, strong acid type large-aperture styrene cationic resin, heterogeneous solvent and dehydrated absolute methanol into an esterification reaction kettle with a condenser according to a proportion, heating to 75-95 ℃, and performing total reflux until a vapor phase pipe on the top of the kettle shows water content of 7-10% by an online moisture tester;
specifically, the heterogeneous solvent is a mixture of cyclohexane and petroleum ether in a proportion of 60-70%, and the petroleum ether is added in a proportion of 30-40%. It should be noted that the heterogeneous solvent in this example is a mixture of cyclohexane and petroleum ether in a mixing ratio of 65:35, wherein the mass ratio of the succinic anhydride to the anhydrous methanol is 1:1.2-1.4, and the addition amount of the heterogeneous solvent is 1.5-2 times of the addition amount of the succinic anhydride.
S2, refluxing with water:
stopping total reflux, switching the liquid phase of the kettle top condenser to a water separator, and quantitatively refluxing the heterogeneous solvent into the kettle by taking the upper solution of the water separator as the heterogeneous solvent, so as to keep the water content of the water content tester of the kettle top vapor phase pipe at 7-10%;
s3, recovering methanol:
the mixed solution at the lower layer of the water separator is an aqueous solution containing methanol, the aqueous solution is pumped into a methanol recovery tower for rectification, methanol with the component of 99.8 percent is slipped out from the top of the tower, and after deep water removal is carried out through a 3A molecular sieve, continuous supplementary feeding is carried out under liquid to an esterification reaction kettle;
specifically, the continuous supplementary feeding of methanol is submerged feeding, and the feeding amount of the methanol is 4-15KG/h. It should be noted that the continuous feeding amount of methanol in this example is preferably 6-13KG/h.
S4, terminating the reaction:
when the water content of the online moisture tester of the vapor phase pipe at the top of the reactor is lower than 1.5-5%, stopping the reflux of the heterogeneous solvent to the reaction kettle, stopping the supplementary feeding of the anhydrous methanol, distilling and extracting the solvent in the reaction kettle, obtaining a crude product of dimethyl succinate with the content of more than or equal to 93%, and sending the crude product to a refining process for purification to obtain the dimethyl succinate with the content of more than or equal to 99.3%.
Compared with the traditional process, the invention can reduce the generation of nearly half of reaction water, thereby reducing the separation energy consumption; by utilizing the azeotropic characteristic of water and heterogeneous solvent, the reaction water is continuously brought out from the reaction system, the forward progress of the reaction is promoted, the reaction efficiency is improved, the reaction time is greatly shortened, the complicated intermediate treatment process in the traditional process is reduced, the method is used for industrial production, and has strong operability, high operation elasticity and higher product yield. The raw materials and the solvent are recycled, so that near zero emission is realized to the greatest extent, and the aim of clean production is fulfilled. The invention has strong plasticity and can realize the joint production with the device for producing the succinic anhydride by the maleic anhydride hydrogenation.
Reaction principle and equation
The reaction equation is as follows:
1. the raw material of the invention is succinic anhydride, which avoids the defects of high equipment requirement, large environmental pollution, slow reaction and the like of synthesizing succinic acid into succinic acid dimethyl ester;
2. the production process can realize continuous production, and has strong operability and high stability;
3. in the production process, the azeotropic characteristic of the heterogeneous solvent and water is fully utilized, the reaction water in a reaction system is effectively removed, the forward progress of the reaction is quickened, the separation process is simplified, the conversion rate of the reaction is improved, the production cost is reduced, and the reaction is more thoroughly carried out by adopting an azeotropic circulation process method;
in conclusion, the method has the advantages of reasonable process, high operation elasticity, high purity and good quality of the prepared product, rapid preparation reaction and convenience for realizing large-scale industrialization.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims.
Claims (6)
1. The preparation method of dimethyl succinate based on azeotropic circulation is characterized by comprising the following steps:
s1, initial reaction:
adding succinic anhydride, a catalyst, a heterogeneous solvent and dehydrated absolute methanol into an esterification reaction kettle with a condenser according to a set proportion, heating, and then heating to a set temperature, and starting total reflux until the moisture content in the esterification reaction kettle reaches a set threshold;
s2, refluxing with water:
stopping total reflux, switching the liquid phase of the condenser to a water separator, and quantitatively refluxing the heterogeneous solvent into the esterification reaction kettle by using the upper solution of the water separator as the heterogeneous solvent, so as to keep the water content of the water content tester of the vapor phase pipe at the top of the esterification reaction kettle between set thresholds;
s3, recovering methanol:
feeding the mixed solution of the lower layer of the water knockout drum and the aqueous solution containing methanol into a methanol recovery tower for rectification, allowing 99.8% methanol to flow out from the top of the tower, performing deep water removal through a 3A molecular sieve, and performing submerged continuous supplementary feeding to an esterification reaction kettle;
s4, terminating the reaction:
when the water content of the online moisture tester of the vapor phase pipe at the top of the reactor is lower than 1.5-5%, stopping the reflux of the heterogeneous solvent to the reaction kettle, stopping the supplementary feeding of the anhydrous methanol, distilling and extracting the solvent in the reaction kettle, obtaining a crude product of dimethyl succinate with the content of more than or equal to 93%, and purifying the crude product to obtain the dimethyl succinate with the content of more than or equal to 99.3%.
2. The method for preparing dimethyl succinate based on azeotropic circulation according to claim 1, wherein the catalyst in the step S1 is a strong acid type large pore size styrene type cationic resin; the temperature is set to be 75-95 ℃ in the step S1; the moisture content in the step S1 is set to 7-10 percent.
3. The method for preparing dimethyl succinate based on azeotropic circulation according to claim 1, wherein the heterogeneous solvent in the step S1 is a mixture of cyclohexane and petroleum ether in a proportion of 60-70% and the petroleum ether in a proportion of 30-40%.
4. The process for preparing dimethyl succinate based on azeotropic circulation according to claim 1, wherein the continuous supplementary feeding of methanol in the step S3 is a submerged feeding and the feeding amount of methanol is 4-15KG/h.
5. The method for preparing dimethyl succinate based on azeotropic circulation according to claim 1, wherein the mass ratio of succinic anhydride to anhydrous methanol in the step S1 is 1:1.2-1.4.
6. The process for preparing dimethyl succinate based on azeotropic circulation according to claim 1 or 2, wherein the addition amount of the heterogeneous solvent is 1.5 to 2 times the addition amount of the succinic anhydride.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202310835711.XA CN116854589A (en) | 2023-07-10 | 2023-07-10 | Dimethyl succinate preparation method based on azeotropic circulation |
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| CN202310835711.XA CN116854589A (en) | 2023-07-10 | 2023-07-10 | Dimethyl succinate preparation method based on azeotropic circulation |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118638039A (en) * | 2024-08-12 | 2024-09-13 | 安徽新秀化学股份有限公司 | Preparation method and application of hindered amine light stabilizer 622 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118638039A (en) * | 2024-08-12 | 2024-09-13 | 安徽新秀化学股份有限公司 | Preparation method and application of hindered amine light stabilizer 622 |
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