Supported solid acid catalyst and preparation method thereof

Abstract

The invention relates to a supported solid acid catalyst and a preparation method thereof. According to the supported solid acid catalyst, dodecaphosphotungstic heteropoly acid istaken as a matrix, Zn < 2 + > modification is carried out by a sol-gel method, so that the supported Zn3 (PW12O40) 2 / SiO2 solid acid catalyst is synthesized. The catalyst has the advantages of low toxicity, no corrosion, easiness in removal from products, high reaction activity and selectivity and narrow distribution coefficient, is easy to produce and process, mild in reaction condition and low in requirement on processing equipment; solvents arenot needed to be addedin the preparation process, so that reaction steps can be greatly reduced, and the production cost can be effectively reduced.

Description

technical field [0001] The invention belongs to the technical field of fine chemical synthesis, and in particular relates to a supported solid acid catalyst and a preparation method. Background technique [0002] Solid acid catalysts are an important class of acid-base catalysts and are widely used in catalytic reactions of ionic mechanisms. [0003] However, the applicant found that the existing solid acid catalysts on the market are highly toxic and highly corrosive, and are difficult to remove from processed products, and also have the disadvantages of poor reactivity and selectivity. Moreover, the production and processing of these solid acid catalysts are relatively complicated, and the requirements for production and processing equipment are high, resulting in high production costs, which are difficult to reduce. For example: phosphotungstic acid (H 3 PW 12 o 40 ·nH 2 O, HPW) is a solid oxygen-containing heteropolyacid with Keggin structure, which has strong acidi...

AI Technical Summary

Problems solved by technology

[0003] However, the applicant found that: the existing solid acid catalysts on the market all have high toxicity and strong corrosiveness, and it is difficult to remove them from the processed products Clean up, there are also the defects of poor reactivity and selectivity, and the production and processing of these solid acid catalysts are relatively complicated, and the requirements for production and processing equipment are high, resulting in high production costs and difficult to reduce

For example: phosphotungstic acid (H 3 PW 12 o 40 ·nH 2 O, HPW) is a solid oxygen-containing heteropolyacid with Keggin structure, which has strong acidity, high catalytic activity and stability, and is widely used in olefin hydration, dehydration, esterification, alkylation and epoxidation, etc. During the reaction; however, the phosphotungstic acid catalyst has a small specific surface area and is easily soluble in polar solvents such as water and alcohol, making it difficult to separate from the reaction system

Images