CN117624440A - Super-crosslinked porous polymer solid acid material and preparation method and application thereof - Google Patents

Super-crosslinked porous polymer solid acid material and preparation method and application thereof Download PDF

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CN117624440A
CN117624440A CN202311412848.0A CN202311412848A CN117624440A CN 117624440 A CN117624440 A CN 117624440A CN 202311412848 A CN202311412848 A CN 202311412848A CN 117624440 A CN117624440 A CN 117624440A
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pdvb
super
porous polymer
solid acid
acid
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郑依洋
沈永淼
陈柏江
张悦悦
雷子俊
金加辉
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Zhejiang University Of Technology Shengzhou Innovation Research Institute Co ltd
Zhejiang Sci Tech University ZSTU
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Zhejiang University Of Technology Shengzhou Innovation Research Institute Co ltd
Zhejiang Sci Tech University ZSTU
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Abstract

The invention discloses a super-crosslinked porous polymer solid acid material, a preparation method and application thereof, belonging to the technical field of solid acid synthesis, wherein divinylbenzene is used as a raw material, and sulfonic acid groups are introduced by copolymerization, post-sulfonation and the like to form the super-crosslinked porous polymer solid acid material PDVB-SO 3 H‑SO 3 H is used as an acid catalyst for catalyzing the synthesis of thioketal at normal temperature, and compared with the traditional homogeneous acid catalysts such as sulfuric acid, p-toluenesulfonic acid and the like, the porous organic solid acid polymer has good catalytic activity at normal temperature and under mild conditions,Wide substrate applicability, high specific surface area, super strong acid strength, adjustable hydrophobicity, good recycling property and the like, and has great application potential in industry.

Description

Super-crosslinked porous polymer solid acid material and preparation method and application thereof
Technical Field
The invention relates to a super-crosslinked porous polymer solid acid material, a preparation method and application thereof, in particular to a preparation method of a porous sulfonic acid group solid acid polymer, which can be used for synthesizing thioketal by normal-temperature catalysis and belongs to the technical field of solid acid catalyst synthesis.
Background
Acid catalysis has received considerable attention over the last two decades for its wide application in the fields of oil refining, biomass conversion, green chemical processes, fine chemical engineering, and the like.
The traditional industry uses a large amount of homogeneous acid, requires complicated post-treatment, is easy to generate a large amount of waste liquid and waste residues, is difficult to regenerate, has serious equipment corrosion and the like. The solid acid is a typical heterogeneous catalyst, has the advantages of adjustable acid center, simple post-treatment, repeated utilization, separation in a reaction medium, reduction corrosion, improvement of the reproducibility, improvement of the selectivity of products and the like, and can effectively overcome the problems. The production of fine chemicals using heterogeneous acids has received considerable attention. Various solid acids have therefore been developed to replace homogeneity. Typically, the solid acid is a zeolite, a heteropolyacid, a sulfated metal oxide, and an ion exchange resin. The traditional solid acid has the defects of small specific surface area, poor thermal stability, poor reusability and the like, can be used for acid catalytic reactions such as esterification reaction, hydrolysis reaction and the like, and water is usually used as a typical byproduct in a plurality of acid catalytic reactions, so that the opposite reactions and the leaching of active sites are further caused.
In addition, with the improvement of living standard, the requirements of people on the aspects of flavor, aroma, taste and the like of foods are increasingly improved, and the development of the edible spice and essence industry is greatly promoted. The synthesis of edible flavors with new flavors has also become a research hotspot in the flavor industry in recent years. As a new type of perfume, the mercaptal (ketone) class of compounds is gaining increasing attention in the perfume community. This is one of the most important uses of the mercaptal (ketone). The substances are increasingly valued by the perfume community because of their good stability, strong fragrance, low threshold and various styles after dilution. Some substances have been detected from natural fragrance components. Some substances have been synthesized abroad and applied to flavoring. Such fragrances have begun to be used in perfumery in China, and thus, development and research of the class of thioketals (ketones) has become more significant.
Therefore, a high-surface-area, high-catalytic-performance and good-recycling-performance hydrophobic high-efficiency mesoporous polymer solid strong acid is needed to be used as a catalyst for synthesizing and preparing the mercaptal (ketone).
Disclosure of Invention
In view of the problems in the prior art, a first aspect of the present invention aims to provide a super-crosslinked porous polymer solid acid material, which solves the problem of poor performance of the existing solid acid.
The technical scheme adopted by the invention is as follows:
a hypercrosslinked porous polymeric solid acid material characterized by: the solid acid material is PDVB-SO 3 H-SO 3 H solid strong acid, PDVB-SO 3 H-SO 3 BET surface area of H solid strong acid is 569m 2 /g。
The second aspect of the invention aims to provide a preparation method of a super-crosslinked porous polymer solid acid material, which is characterized by comprising the following steps:
(1)PDVB-SO 3 synthesis of H porous Polymer
In DVB/AIBN/THF/H 2 O is an initial system and is copolymerized with sodium ethylene sulfonate under solvothermal conditions to synthesize PDVB-SO 3 H porous polymer.
Further:
in the step (1), the content of the sulfo group is adjusted by changing the molar ratio of DVB to sodium ethylene sulfonate, preferably the molar ratio of DVB to sodium ethylene sulfonate is 5:1 to 20:1, and particularly preferably 10:1.
The solvent is selected from any one of tetrahydrofuran, ethyl acetate, acetone and the like.
The copolymerization temperature is 80 to 150℃and preferably 100 ℃.
The copolymerization time is 12 to 36 hours, preferably 24 hours.
In step (1): 2.0g DVB was added to a solution containing 0.05g AIBN and 20mL THF, then 1mL water was added, then 0.2g sodium ethylene sulfonate was introduced; stirring at room temperature to form a uniform solution, solvothermal treating the mixture at 100deg.C for 24 hr to obtain PDVB-SO 3 Na, PDVB-SO 3 N is further acidified to obtain PDVB-SO 3 H。
(2)PDVB-SO 3 H-SO 3 Synthesis of H solid strong acid
PDVB-SO using chlorosulfonic acid 3 H is subject to sulfonation reaction to synthesize PDVB-SO 3 H-SO 3 H solid strong acid.
In the step (2): the sulfonation reaction temperature is 60 to 120 ℃, preferably 80 ℃. The sulfonation reaction time is 12 to 36 hours, preferably 24 hours.
In the step (2): 1g PDVB-SO 3 H was added to a flask containing 100mL of methylene chloride, followed by 15mL of chlorosulfonic acid, stirred at 80℃for 24 hours, and filtered to obtain PDVB-SO 3 H-SO 3 H, washing with ethanol to neutrality, and vacuum drying at 80deg.C to obtain PDVB-SO 3 H-SO 3 H solid strong acid.
The third aspect of the invention aims to provide an application of a super-crosslinked porous polymer solid acid material in synthesizing thioketal, which is characterized in that: at room temperature, adding a catalyst PDVB-SO in the acetal ketone reaction of carbonyl and mercaptan 3 H-SO 3 And H, the conversion rate and the selectivity of the reaction can be effectively improved.
Taking ketal reaction of cyclohexanone and 1, 2-ethanedithiol as an example, the reaction equation involved in the present invention is as follows:
as shown in the formula, the super-crosslinked porous polymer solid acid material PDVB-SO prepared by the invention 3 H-SO 3 H provides a new method for synthesizing thioketal at room temperature, and uses PDVB-SO 3 H-SO 3 H is a catalyst, the yield and the selectivity of the product are obviously improved, and no refractory toxic and harmful substances are generated after the reaction is finished.
The beneficial effects of the invention are as follows:
1. the invention relates to a method for preparing porous sulfonic solid acid polymer and synthesizing thioketal by normal temperature catalysis. The divinylbenzene is used as raw material, sulfonic acid groups are introduced by means of sulfonation after copolymerization, etc., and the super cross-linked porous polymer (PDVB-SO) is formed 3 H-SO 3 H) And the catalyst is used as an acidic catalyst for catalyzing the synthesis of thioketal at normal temperature. Compared with the traditional homogeneous acid catalysts such as sulfuric acid, p-toluenesulfonic acid and the like, the porous organic solid acid polymer has the advantages of good catalytic activity, wide substrate applicability, high specific surface area, super-strong acid strength, adjustable hydrophobicity, good recycling property and the like under the condition of normal temperature and temperature, and has great application potential in industry.
2. The PDVB-SO synthesized by the invention 3 H-SO 3 The H solid acid catalyst has good catalytic performance and selectivity in the application of acetal ketone synthesis, and can accurately catalyze carbonyl and mercaptan to generate acetal ketone reaction. The catalyst has good catalytic effect on alkyl ketone and 1, 2-ethanedithiol, and under the same reaction condition, the conversion rate can reach more than 84% and the selectivity can reach more than 88%.
The invention is further illustrated by the following description of the drawings and specific embodiments.
Drawings
FIG. 1 shows the N2 adsorption isotherm and pore size distribution (a: PDVB-SO) of the catalyst prepared in example 1 3 H and b: PDVB-SO 3 H-SO 3 H)。
Fig. 2 is a transmission electron microscope image of the catalyst prepared in example 1 (a:PDVB-SO 3 h and b: PDVB-SO 3 H-SO 3 H)。
FIG. 3 is a FT-IR spectrum of a different catalyst (A: PDVB, B: PDVB-SO) 3 H and C: PDVB-SO 3 H-SO 3 H)。
FIG. 4 shows TG of the catalyst prepared in example 1 and Nafion NR50 (a: nafion NR50 and b: PDVB-SO) 3 H-SO 3 H)。
Fig. 5 is a chromatogram, mass spectrum of the thioketal product prepared in example 2.
Detailed Description
The present invention is described below with reference to specific examples, which are only for illustrating the technical scheme of the present invention and do not limit the protection scope of the present invention.
The materials and reagents used in the invention are as follows:
5977B GC/MSD chromatograph-mass spectrometer (agilent technologies limited); WNR-I400M Nuclear magnetic resonance spectrometer (oxford Spectroscopy Co., ltd.); DF-101S constant temperature magnetic stirrer (Huizhou Hui instruments devices Co., ltd.); 2000A rotary evaporator (ohus instruments limited); PX174ZHE electronic balance (Shanghai-constant scientific instruments limited). Cyclohexanone (AR), 1, 2-ethanedithiol (AR), anhydrous magnesium sulfate were purchased from aladine chemical company limited (Shanghai, china); other reagents were either commercially available analytically pure or chemically pure.
Example 1: synthesis catalyst PDVB-SO 3 H-SO 3 H
(1)PDVB-SO 3 Synthesis of H porous Polymer
2.0g of DVB was added to a solution containing 0.05g of AIBN and 20mL of THF, then 1mL of water was added, then 0.2g of sodium vinylsulfonate was introduced. After stirring at room temperature to form a homogeneous solution, the mixture was subjected to solvothermal treatment at 100 ℃ for 24 hours. Evaporating at room temperature to obtain PDVB-SO with integral morphology 3 Na sample, PDVB-SO 3 Further acidifying Na sample with 1M sulfuric acid to obtain PDVB-SO 3 H。
(2) Catalyst PDVB-SO 3 H-SO 3 Synthesis of H
Will be 1g PDVB-SO 3 H was added to a flask containing 100mL of methylene chloride, followed by 15mL of chlorosulfonic acid, stirred at 80℃for 24 hours, and filtered to obtain PDVB-SO 3 H-SO 3 H, washing with a large amount of ethanol to neutrality, and vacuum drying at 80deg.C to obtain PDVB-SO 3 H-SO 3 H solid strong acid, yield 86%.
Product confirmation:
fig. 1 is an N2 adsorption isotherm and pore size distribution of the catalyst prepared in example 1, fig. 2 is a transmission electron microscopy image of the catalyst prepared in example 1, fig. 3 is an FT-IR spectrum of the catalyst prepared in example 1, and fig. 4 is a TG curve of the catalyst prepared in example 1 and Nafion NR 50.
As shown in fig. 1-4:
PDVB-SO prepared in example 1 3 H-SO 3 The H solid strong acid has larger BET surface area and PDVB-SO 3 H-SO 3 H BET surface area of 569m 2 Per g, far higher than NafionNR50/0 (0.02 m 2 Per g), lower than SBA-15-SO 3 H and H-type zeolite (820-550 m) 2 /g)。
PDVB-SO prepared in example 1 3 H-SO 3 H solid strong acid loads more sulfonic groups and has stronger acid capacity, and the PDVB-SO synthesized by the invention 3 H and PDVB-SO 3 H-SO 3 H samples were clearly found to be 1190cm in FIG. 3, compared to PDVB -1 The presence of characteristic peaks of nearby sulfonic groups, which indicate the presence of sulfonic groups in these samples, is notable for the presence of sulfonic groups in PDVB-SO 3 After H is further introduced into aryl sulfonic acid groups, the C-S bond peak intensity is obviously enhanced, so that more sulfonic acid groups are supported, and the acid capacity is enhanced.
PDVB-SO prepared in example 1 3 H-SO 3 The H solid strong acid has good stability, and the PDVB-SO synthesized by the invention 3 H-SO 3 The decomposition temperatures of the acid groups (373 ℃) and the polymer network (500 ℃) in H are far higher than Nafion NR50 (335 ℃ and 460 ℃) which is one of the most stable acid resins, which shows that the acid groups have excellent heat stability and PDVB-SO 3 HSO 2 CF 3 The superior stability of (a) results from the presence of electron withdrawing groups in the sample and the highly crosslinked polymer network。
Alternative examples 1-1 to 1-6
The preparation methods of the alternative examples 1-1 to 1-6 are the same as in example 1, except that: the amounts of sodium vinylsulfonate, chlorosulfonic acid, and solvent selections were varied as shown in table 1.
TABLE 1,
As can be seen from table 1: the combination of cost and yield found that when tetrahydrofuran was used as the solvent, sodium vinylsulfonate was used in an amount of 0.2g, and chlorosulfonic acid was used in an amount of 10ml, the catalyst yield was preferably 81%.
Example 2: catalytic synthesis of thioketals
0.05g of the catalyst prepared in example 1 was added and mixed with a solution containing 10mmol of cyclohexanone and 15mmol of 1, 2-ethanedithiol, and anhydrous magnesium sulfate as a water scavenger was added, and the reaction was stirred at room temperature for 24 hours, and samples were taken at regular time during the reaction, and GC-MS qualitative and GC quantitative analyses were performed, with a yield of 90%, a conversion of 99%, and conversion and selectivity calculations of the reaction were all based on cyclohexanone.
Alternative examples 2-1 to 2-5
The preparation method of the alternative examples 2-1 to 2-5 is the same as that of example 2, except that: different substrates were added and tested for reaction yield and conversion, respectively, as shown in table 2.
TABLE 2,
As can be seen from table 2:
comprehensive cost and yield findings, PDVB-SO 3 H-SO 3 H solid acid catalyst inIn the application of acetal ketone synthesis, good catalytic performance and selectivity are shown, and acetal ketone reaction between carbonyl and mercaptan can be accurately catalyzed. The catalyst has good catalytic effect on alkyl ketone and 1, 2-ethanedithiol, the conversion rate can reach more than 84%, the selectivity can reach more than 88%, but when the group exists at the position 4, the reaction is affected by steric effect to different degrees, so that the conversion rate and the selectivity are reduced. For cycloalkyl ketones, the conversion and selectivity are as reactive as alkyl ketones, but the partial reaction conversion is lower. The catalyst also has catalytic effect on the synthesis of benzene ring substituted derivatives, and the reaction data can obviously show that the reactivity is less influenced by different groups, the conversion rate and the selectivity are good, but the reaction data can be influenced by steric hindrance. The product was confirmed by GC and GC-MS.
Alternative examples 2-6 to 2-11: influence of different catalysts on the thioketal Synthesis reaction
The preparation method of the alternative examples 2-6 to 2-11 is the same as that of example 2, except that: different catalysts and amounts were selected and the effect of each catalyst on the thioketal synthesis reaction was tested and shown in table 3.
TABLE 3 Table 3
As can be seen from table 3:
(1) With increasing catalyst usage, the product yield increases gradually, when PDVB-SO is used 3 H-SO 3 When H is used as the catalyst and the dosage is 0.05g, the benefit is relatively best, the yield is 90%, the conversion rate is 99%, the dosage of the catalyst is further increased, and the effect is not obviously improved.
(2) It can be seen from the combination of example 2 and alternatives 2-9 to 2-12 that the novel catalyst PDVB-SO compared with other catalysts 3 H-SO 3 H in the catalytic synthesis of thioketal reaction, hasBetter effect.
Example 3: amplification reaction
To simulate the actual industrial production, the typical ketal reaction of cyclohexanone and 1, 2-ethanedithiol was scaled up. The substrate dosage in the original experiment is amplified twenty times.
Experimental route: 1g of catalyst is added into a solution containing 200mmol of cyclohexanone and 300mmol of 1, 2-ethanedithiol, anhydrous magnesium sulfate as a water removing agent is added, stirring reaction is carried out at normal temperature for 24 hours, sampling is carried out at regular time in the reaction process, GC-MS qualitative and GC quantitative analysis is carried out, the yield is 88%, the conversion rate is 99%, and the conversion rate and the selectivity of the reaction are calculated by taking cyclohexanone as a reference substance.
Summarizing:
the invention prepares a new PDVB-SO 3 H-SO 3 H solid acid catalyst, PDVB-SO 3 H-SO 3 H exhibits unique characteristics including large surface area, hydrophobic and oleophilic networks, enhanced acid strength and uniform acid distribution. The catalyst can be used for preparing the sulfur ketal with high efficiency at room temperature, which has potential significance in biomass conversion in green chemical process.
It is to be understood that the foregoing detailed description of the invention is merely illustrative of the invention and is not limited to the embodiments of the invention. It will be understood by those of ordinary skill in the art that the present invention may be modified or substituted for elements thereof to achieve the same technical effects; as long as the use requirement is met, the invention is within the protection scope of the invention.

Claims (10)

1. The preparation method of the super-crosslinked porous polymer solid acid material is characterized by comprising the following steps of:
(1)PDVB-SO 3 synthesis of H porous Polymer
DVB, AIBN, THF, H by 2 O is an initial system and is copolymerized with sodium ethylene sulfonate under solvothermal conditions to synthesize PDVB-SO 3 H a porous polymer;
(2)PDVB-SO 3 H-SO 3 synthesis of H solid strong acid
PDVB-SO using chlorosulfonic acid 3 H is subject to sulfonation reaction to synthesize PDVB-SO 3 H-SO 3 H solid strong acid.
2. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 1, wherein the method comprises the following steps: in the step (1), the molar ratio of DVB to sodium ethylene sulfonate is 5:1-20:1.
3. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 2, wherein the method comprises the following steps: in the step (1), the molar ratio of DVB to sodium ethylene sulfonate is 10:1.
4. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 1, wherein the method comprises the following steps: in the step (1), the solvent is selected from any one of tetrahydrofuran, ethyl acetate, acetone and the like.
5. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 1, wherein the method comprises the following steps: in the step (1), the copolymerization reaction temperature is 80-150 ℃ and the copolymerization reaction time is 12-36 hours.
6. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 1, wherein the method comprises the following steps: in the step (1), the copolymerization reaction temperature is 100 ℃, and the copolymerization reaction time is 24 hours.
7. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 1, wherein the method comprises the following steps: in the step (2): the sulfonation reaction temperature is 60-120 ℃, and the sulfonation reaction time is 12-36 hours.
8. The method for preparing the super-crosslinked porous polymer solid acid material according to claim 1, wherein the method comprises the following steps: in the step (2): the sulfonation reaction temperature was 80℃and the sulfonation reaction time was 24 hours.
9. A hypercrosslinked porous polymer solid acid material synthesized by the method of any one of claims 1 to 8, characterized in that: PDVB-SO 3 H-SO 3 BET surface area of H solid strong acid is 569m 2 /g。
10. Use of a supercrosslinked porous polymeric solid acid material synthesized by the method of any one of claims 1-8 in the synthesis of a thioketal.
CN202311412848.0A 2023-10-30 2023-10-30 Super-crosslinked porous polymer solid acid material and preparation method and application thereof Pending CN117624440A (en)

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