CN110586184A - Solid acid and preparation method and application thereof - Google Patents
Solid acid and preparation method and application thereof Download PDFInfo
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- CN110586184A CN110586184A CN201910877903.0A CN201910877903A CN110586184A CN 110586184 A CN110586184 A CN 110586184A CN 201910877903 A CN201910877903 A CN 201910877903A CN 110586184 A CN110586184 A CN 110586184A
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- acid
- solid acid
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- concentrated sulfuric
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- 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
- B01J31/06—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
- B01J31/08—Ion-exchange resins
- B01J31/10—Ion-exchange resins sulfonated
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- 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
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- 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
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- 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
Abstract
The invention relates to the technical field of solid acid, and particularly discloses solid acid and a preparation method and application thereof. The preparation method of the solid acid comprises the following steps: reacting a phenolic compound with concentrated sulfuric acid to obtain aromatic phenolsulfonic acid; and carrying out condensation reaction on the aromatic phenolsulfonic acid and the aldehyde compound under the catalysis of an acid catalyst to obtain the solid acid. According to the invention, the phenolic compound and concentrated sulfuric acid are firstly reacted to generate aromatic phenolsulfonic acid, and the sulfonic group is firmly connected on the benzene ring, so that the acid is firmly loaded, the thermal stability is improved, the acid loss is avoided, a foundation is provided for the subsequent polymerization reaction with aldehydes, and the solid acid with long service life is prepared.
Description
Technical Field
The invention relates to the technical field of solid acid, in particular to solid acid and a preparation method and application thereof.
Background
As is well known, inorganic acids are widely used as catalysts for the synthesis of fine chemicals due to their high activity and low cost. However, inorganic acid also has inevitable disadvantages, such as a large amount of waste acid liquid which needs to be treated, corrodes equipment, is not easy to be separated from a product, is difficult to be recycled and only can be discarded, so that the production cost is increased, and the environment is seriously polluted. Therefore, the development of solid acid catalysts to replace inorganic acids is the focus and focus of current research. Solid acid catalysts using zeolite, metal oxide, ion exchange resin, or the like as a carrier have been studied extensively. However, most of these solid acid catalysts have the disadvantages of low porosity, undesirable morphology and structure, poor thermal stability, unstable acidity, etc., and are deactivated relatively quickly. The best solid acid catalyst at present is super-strong acid Nafion resin of perfluorinated sulfonic acid type ester developed by the Du's corporation in the last sixty years, and the super-strong acid Nafion resin is used in a plurality of synthetic reactions and shows super-good catalytic effect. However, the Nafion perfluorosulfonic acid resin has the defects of high preparation cost, difficult control of load preparation and the like, and limits the industrial popularization and application of the Nafion perfluorosulfonic acid resin.
Disclosure of Invention
Aiming at the problems of poor thermal stability, easy loss of acidity, short service life, high cost and the like of the existing solid acid catalyst, the invention provides a preparation method of solid acid.
And, a solid acid.
And, a use of the solid acid.
In order to achieve the purpose of the invention, the embodiment of the invention adopts the following technical scheme:
a method for preparing a solid acid, comprising at least the steps of:
step a, reacting a phenolic compound with concentrated sulfuric acid at 85-100 ℃ to obtain aromatic phenolsulfonic acid;
and b, carrying out condensation reaction on the aromatic phenolsulfonic acid and the aldehyde compound at the temperature of 60-130 ℃ under the catalysis of an acid catalyst to obtain the solid acid.
Compared with the prior art, the preparation method of the solid acid provided by the invention has the following advantages:
the preparation method provided by the invention is simple, the aromatic phenolsulfonic acid is generated by the reaction of the phenolic compound and concentrated sulfuric acid, the sulfonic group is firmly connected on the benzene ring, so that the acid is firmly loaded, the phenolic hydroxyl group and the aldehyde group are subjected to condensation reaction, the sulfonic group is fixed on the resin, and the prepared solid acid has long service life and high thermal stability.
Preferably, the phenolic compound and H in the concentrated sulfuric acid2SO4The molar ratio of the concentrated sulfuric acid is 1:1-2, and the mass concentration of the concentrated sulfuric acid is 80-90%.
The mol ratio of the phenolic compound to the concentrated sulfuric acid is preferably controlled, so that the sulfonic group is connected to the benzene ring, and the subsequent condensation reaction with the aldehyde can be smoothly carried out. If the number of the sulfonic acid groups is too large, the aromatic phenol sulfonic acid has large steric hindrance, so that the subsequent condensation reaction with aldehydes is difficult to carry out.
Preferably, the phenolic compound is a monophenolic compound.
The o-, m-and p-positions of the phenolic hydroxyl groups can be reacted, and if the content of the phenolic hydroxyl groups is too high, the subsequent condensation reaction with aldehydes is difficult to perform due to the large steric hindrance of the aromatic phenolsulfonic acid.
Further preferably, the phenolic compound is phenol, cresol, aminophenol or guaiacol.
Preferably, the molar ratio of the aromatic phenolsulfonic acid to the aldehyde is 1: 0.1-10.
The proportion of aromatic phenolsulfonic acid to aldehyde is preferably controlled, so that phenolic hydroxyl and aldehyde group are fully condensed, sulfonic acid group is fixed on resin through phenolic aldehyde condensation, and the stability of solid acid is ensured.
Preferably, the aldehyde is at least one of formaldehyde, benzaldehyde, acetaldehyde or glyoxal.
Preferably, the acidic catalyst is hydrochloric acid, sulfuric acid, nitric acid or oxalic acid.
Preferably, in step a, the temperature of the reaction is 85-100 ℃.
Preferably, in step a, the reaction time is 6-10 h.
Preferably, in step b, the time of the condensation reaction is 8-24 h.
Preferably, in step b, the condensation reaction has a pH of 4 to 6.
Preferably, in step b, the temperature of the condensation reaction is 60-130 ℃.
Further preferably, in step b, the temperature of the condensation reaction is 80-120 ℃.
Furthermore, the solid acid is prepared by the preparation method of the solid acid.
According to the invention, the aromatic phenolsulfonic acid is generated by reacting the phenolic compound with concentrated sulfuric acid, and the sulfonic group is firmly connected on the benzene ring, so that the acid is firmly loaded, the thermal stability is improved, the acid loss is avoided, a foundation is provided for the subsequent polymerization reaction with aldehydes, the service life of the prepared solid acid is longer, and the acid is more stable.
The acid value of the solid acid prepared by the method can reach 4mmol/g, the thermal decomposition temperature can reach 280 ℃, the acidity is strong, and the thermal stability is high.
Further, the invention also provides the application of the solid acid as a catalyst for esterification reaction or ester exchange reaction.
The solid acid prepared by the invention is used as a catalyst for catalyzing esterification reaction, the esterification reaction yield is high, after 5 times of recovery, the esterification reaction yield is not obviously reduced under the same condition, and the yield is still over 99 percent.
The solid acid prepared by the invention is used as a catalyst for catalyzing transesterification, the transesterification conversion rate reaches 100%, and after 5 times of recovery, the conversion rate of the transesterification under the same condition is still 100%, which shows that the solid acid prepared by the invention has long service life, high thermal stability and stable acidity.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
The embodiment of the invention provides a preparation method of solid acid, which comprises the following steps:
step a, weighing phenol and concentrated sulfuric acid according to the molar ratio of 1:1.3, firstly dispersing the phenol in 70 wt% of the concentrated sulfuric acid, then adding the rest concentrated sulfuric acid, fully stirring, and reacting for 6 hours at 90 ℃ to obtain aromatic phenolsulfonic acid;
and b, mixing the aromatic phenolsulfonic acid and formaldehyde according to a molar ratio of 1:0.1, adding hydrochloric acid to adjust the pH value to 4, carrying out condensation reaction at 80 ℃ for 16h, carrying out rotary evaporation dehydration, washing with deionized water until no sulfate radical chloride ion is detected, and carrying out vacuum drying at 80 ℃ for 6h to obtain the solid acid.
The mass concentration of the concentrated sulfuric acid is 80%.
Example 2
The embodiment of the invention provides a preparation method of solid acid, which comprises the following steps:
step a, weighing aminophenol and concentrated sulfuric acid according to a molar ratio of 1:2, slowly dispersing the aminophenol in the concentrated sulfuric acid, fully stirring, and reacting for 8 hours at 85 ℃ to obtain aromatic phenolsulfonic acid;
and b, mixing the aromatic phenolsulfonic acid and acetaldehyde according to a molar ratio of 1:1, adding sulfuric acid to adjust the pH value to 5, carrying out condensation reaction at 90 ℃ for 14h, carrying out rotary evaporation dehydration, washing with deionized water until no sulfate radical chloride ion is detected, and carrying out vacuum drying at 80 ℃ for 6h to obtain the solid acid.
The mass concentration of the concentrated sulfuric acid is 85%.
Example 3
The embodiment of the invention provides a preparation method of solid acid, which comprises the following steps:
step a, weighing guaiacol and concentrated sulfuric acid according to the molar ratio of 1:1.5, firstly dispersing the guaiacol in 70 wt% of concentrated sulfuric acid, then adding the rest concentrated sulfuric acid, fully stirring, and reacting for 10 hours at 100 ℃ to obtain aromatic phenolsulfonic acid;
and b, mixing the aromatic phenolsulfonic acid and benzaldehyde according to a molar ratio of 1:0.8, adding oxalic acid to adjust the pH value to 6, performing condensation reaction at 130 ℃ for 8 hours, performing rotary evaporation dehydration, washing with deionized water until no sulfate radical chloride ion is detected, and performing vacuum drying at 80 ℃ for 6 hours to obtain the solid acid.
The mass concentration of the concentrated sulfuric acid is 90%.
Example 4
The embodiment of the invention provides a preparation method of solid acid, which comprises the following steps:
step a, weighing p-methylphenol and concentrated sulfuric acid according to the molar ratio of 1:1, firstly dispersing the p-methylphenol in 70 wt% of concentrated sulfuric acid, then adding the rest concentrated sulfuric acid, fully stirring, and reacting for 7 hours at the temperature of 95 ℃ to obtain aromatic phenol sulfonic acid;
and b, mixing the aromatic phenolsulfonic acid and glyoxal according to a molar ratio of 1:10, adding nitric acid to adjust the pH value to 5.5, carrying out condensation reaction at 60 ℃ for 24 hours, carrying out rotary evaporation dehydration, washing with deionized water until no sulfate radical chloride ion is detected, and carrying out vacuum drying at 80 ℃ for 6 hours to obtain the solid acid.
The mass concentration of the concentrated sulfuric acid is 80%.
Comparative example 1
The present comparative example provides a method of preparing a solid acid comprising the steps of:
step a, mixing phenol and formaldehyde according to a molar ratio of 1:0.1, adding hydrochloric acid to adjust the pH value to be 4, and carrying out condensation reaction for 16h at 80 ℃ to obtain phenolic resin;
and b, mixing the phenolic resin with concentrated sulfuric acid according to a molar ratio of 1:1.3, reacting for 6 hours at 90 ℃, then carrying out rotary evaporation dehydration, washing with deionized water until no sulfate radical chloride ion is detected, and carrying out vacuum drying for 6 hours at 80 ℃ to obtain the solid acid.
The mass concentration of the concentrated sulfuric acid is 80%.
In order to better illustrate the characteristics of the solid acid provided by the embodiment of the present invention, the solid acids prepared in the following examples 1 to 4 and comparative example 1 were subjected to performance tests, and the test results are shown in the following table 1.
TABLE 1 test results
As can be seen from Table 1, the acid value and thermal stability of the solid acid prepared in the example of the present invention are significantly better than those of comparative example 1, and the solid acid obtained in the example of the present invention has the advantages of strong load on concentrated sulfuric acid, high acid value, strong acidity and excellent thermal stability.
Test example 1
Catalytic esterification reaction
The solid acids prepared in example 1 and comparative example 1 were used as acid catalysts in the esterification reaction, respectively.
The specific reaction process of the esterification reaction is as follows: adding 0.2mol of acetic acid and 0.6mol of isoamyl alcohol into a 250mL three-necked bottle with an electromagnetic stirring device, a thermometer, a reflux condenser pipe and a water separator for heating and stirring, then adding 1g of the solid acid prepared in the example 1 or the comparative example 1 as a catalyst, heating and refluxing for stirring, separating water generated by reaction from the water separator, and reacting for 3 hours to obtain the isoamyl acetate.
Yield-actual yield-100%/theoretical yield
Recovery of solid acid catalyst: after the reaction is finished, the catalyst is filtered and recovered without being washed, and directly enters a circulation test.
The test was repeated: adding the recovered catalyst according to the esterification reaction conditions for reaction. The catalyst was recovered 5 times, the esterification reaction was repeated 5 times, and the yield of isoamyl acetate was as shown in Table 2 below.
TABLE 2 yield
| Number of times of catalyst recovery | Example 1 | Comparative example 1 |
| 0 | 99.20％ | 85％ |
| 1 | 99.10％ | 83％ |
| 2 | 99.10％ | 80％ |
| 3 | 99.20％ | 75％ |
| 4 | 99.10％ | 69％ |
| 5 | 99.0％ | 65％ |
As can be seen from Table 2, the yield of esterification reaction under the same conditions was not significantly decreased after 5 times of recovery of the catalyst of example 1, and was still above 99%, and the yield of the product of examples 2-4 was above 99.0% without changing the esterification reaction conditions after 5 times of recovery of the solid as the acid catalyst in the esterification reaction. The solid acid prepared by the invention has long service life, high thermal stability and stable acidity.
As can be seen from Table 2, the solid acid prepared in comparative example 1, which is used in catalyzing the esterification reaction, is unstable in acidity, short in life, and significantly lower in catalytic efficiency than those of examples 1 to 4.
Test example 2
Catalytic transesterification
The solid acids prepared in example 1 and comparative example 1 were used as acid catalysts in the transesterification reaction, respectively.
The specific reaction process of the ester exchange reaction is as follows: 10g of edible oil, 5g of methanol and 2g of catalyst are added into a 250mL three-necked bottle provided with an electromagnetic stirring device, a thermometer, a reflux condenser tube and a water separator for reaction at the reaction temperature of 90 ℃ for 10-12 hours, and the conversion rate of the ester exchange reaction is 100%.
Recovery of solid acid catalyst: after the reaction is finished, the catalyst is filtered and recovered without being washed, and directly enters a circulation test.
The test was repeated: the recovered catalyst was added to the reaction mixture under the above transesterification conditions to carry out the reaction. The catalyst was recovered 5 times and the transesterification reaction was repeated 5 times, and the conversion of the transesterification reaction was as shown in Table 3 below.
TABLE 3 conversion
| Number of times of catalyst recovery | Example 1 | Comparative example 1 |
| 0 | 100％ | 93％ |
| 1 | 100％ | 90％ |
| 2 | 100％ | 85％ |
| 3 | 100％ | 79％ |
| 4 | 100％ | 75％ |
| 5 | 100％ | 68％ |
As can be seen from Table 3, the conversion rate of transesterification under the same conditions was still 100% after 5 times of recovery of the catalyst, and the conversion rates of the products reached 100% without changing the transesterification conditions after 5 times of recovery of the solid acid prepared in examples 2 to 4 as an acid catalyst in the transesterification. The solid acid prepared by the invention has long service life, high thermal stability and stable acidity.
As can be seen from Table 3, the solid acid prepared in comparative example 1, which is used to catalyze the transesterification reaction, is unstable in acidity, short in life, and significantly less efficient than those of examples 1 to 4.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. A method for preparing solid acid is characterized in that: at least comprises the following steps:
step a, reacting a phenolic compound with concentrated sulfuric acid to obtain aromatic phenolsulfonic acid;
and b, carrying out condensation reaction on the aromatic phenolsulfonic acid and the aldehyde compound under the catalysis of an acid catalyst to obtain the solid acid.
2. The method for producing a solid acid according to claim 1, wherein: the phenolic compound and H in the concentrated sulfuric acid2SO4The molar ratio of the concentrated sulfuric acid is 1:1-2, and the mass concentration of the concentrated sulfuric acid is 80-90%.
3. The method for producing a solid acid according to claim 1, wherein: the phenolic compound is a monophenolic compound.
4. The method for producing a solid acid according to claim 3, wherein: the phenolic compound is phenol, cresol, aminophenol or guaiacol.
5. The method for producing a solid acid according to claim 1, wherein: the molar ratio of the aromatic phenolsulfonic acid to the aldehyde compound is 1: 0.1-10.
6. The method for producing a solid acid according to claim 1, wherein: the aldehyde compound is at least one of formaldehyde, benzaldehyde, acetaldehyde or glyoxal; and/or
The acidic catalyst is hydrochloric acid, sulfuric acid, nitric acid or oxalic acid.
7. The method for producing a solid acid according to claim 1, wherein: in the step a, the reaction temperature is 85-100 ℃; and/or
In the step a, the reaction time is 6-10 h; and/or
In the step b, the temperature of the condensation reaction is 60-130 ℃; and/or
In the step b, the condensation reaction time is 8-24 h; and/or
In the step b, the pH value of the condensation reaction is 4-6.
8. The method for producing a solid acid according to claim 7, wherein: in the step b, the temperature of the condensation reaction is 80-120 ℃.
9. A solid acid characterized by: the solid acid according to any one of claims 1 to 8.
10. Use of the solid acid of claim 9 as a catalyst for esterification or transesterification.
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| CN201910877903.0A CN110586184A (en) | 2019-09-17 | 2019-09-17 | Solid acid and preparation method and application thereof |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101157052A (en) * | 2007-08-07 | 2008-04-09 | 华东师范大学 | A preparation method of carbon base solid acid catalyst |
| CN102125873A (en) * | 2010-12-10 | 2011-07-20 | 绍兴文理学院 | Phenolic resin based solid acid, preparation method and application thereof |
| CN102659592A (en) * | 2012-05-11 | 2012-09-12 | 绍兴文理学院 | Method for synthesizing tributyl citrate by using resorcinol formaldehyde resin based solid acid as catalyst |
-
2019
- 2019-09-17 CN CN201910877903.0A patent/CN110586184A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101157052A (en) * | 2007-08-07 | 2008-04-09 | 华东师范大学 | A preparation method of carbon base solid acid catalyst |
| CN102125873A (en) * | 2010-12-10 | 2011-07-20 | 绍兴文理学院 | Phenolic resin based solid acid, preparation method and application thereof |
| CN102659592A (en) * | 2012-05-11 | 2012-09-12 | 绍兴文理学院 | Method for synthesizing tributyl citrate by using resorcinol formaldehyde resin based solid acid as catalyst |
Non-Patent Citations (3)
| Title |
|---|
| BAOHUA ZHANG ET AL.: "Novel sulfonated carbonaceous materials from p-toluenesulfonic acid/glucose as a high-performance solid-acid catalyst", 《CATALYSIS COMMUNICATIONS》 * |
| 詹盈盈等: "碳基固体酸的制备与应用研究进展", 《浙江化工》 * |
| 赵洋等编著: "《生物柴油发动机燃烧与排放基础》", 30 November 2018, 江苏大学出版社 * |
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Application publication date: 20191220 |