Method for preparing resin assembled heteropoly acid salt catalyst

Abstract

The preparation process of resin assembled heteropoly acid salt catalyst includes the following steps: 1. soaking cationic exchange resin in exchange solution for the hydrogen ion on the resin and the cation capable of forming insoluble salt with heteropoly acid to exchange in exchange degree controlled in 0.5-95 %; 2. soaking the obtained cation exchange resin in heteropoly acid solution for the hydrogen ion in heteropoly acid solution and cation on the resin to exchange, with the exchanged cation and the heteropoly anion producing insoluble heteropoly acid salt depositing onto the surface of the resin in the supported amount of 1-60 wt%; and 3. washing and drying the obtained resin. The resin assembled heteropoly acid salt catalyst has the features of high acid strength, high acid amount, great specific surface area, water insolubility, etc. and is one kind of high performance compound organic-inorganic catalyst capable of being used in various acid catalyzed reactions.

Description

technical field [0001] The invention relates to a method for preparing a resin-assembled heteropolyacid salt catalyst. Background technique [0002] As we all know, more than 85% of the organic reactions need to be carried out under the action of catalysts, or can only be economically valuable under the action of catalysts, and acid-catalyzed reactions occupy the largest proportion among various catalytic reactions. The traditional acid catalyst is H 2 SO 4 , HF, AlCl 3 , BF 3 These catalysts have good low-temperature catalytic activity, but are highly toxic and corrosive, corrode equipment, pollute the environment, and especially pose potential hazards to the health of operators. Therefore, domestic and foreign researches have been conducted in recent decades. Researchers have been working hard to develop environmentally friendly solid acid catalysts to replace liquid acid catalysts. [0003] Heteropolyacids and their salts are a new class of solid acid catalytic mater...

AI Technical Summary

Problems solved by technology

However, heteropolyacids also have the following disadvantages as solid acid catalysts: (1) The specific surface area is small, generally less than 10m 2 / g; (2) Afraid of water, the acid strength of heteropolyacid is related to crystal water, the presence of water affects the acid strength of catalyst, and heteropolyacid is easy to dissolve in water, so if the reaction system contains water, it may cause active group (3) Anhydrous heteropolyacid is in powder state, difficult to form

[0005] As can be seen from the above-mentioned documents, there are the following major problems in the supported heteropolyacid (salt) catalysts prepared by the common loading method at present: (one) when preparing the loaded insoluble heteropolyacid salt catalyst, it is difficult to ensure that the active components are evenly distributed; (two) Using SiO 2 、TiO 2 , SiO 2 , ZrO 2 When the oxide is used as the support, there are also shortcomings such as the interaction between the heteropolyacid and the support to reduce the acidity of the catalyst.