12-Phosphotungstic acid and its Cs salt supported on various porous carriers as catalysts for the synthesis of fructone

A series of 12-Phosphotungstic (PW) acid and its cesium salt catalysts supported on various porous carriers, such as silica gel, mesoporous silica SBA-15, ultra-stable Y (USY) and dealuminated USY were prepared, and their catalytic performances were evaluated in the liquid-phase acetalization of ethyl acetoacetate and ethylene glycol into fructone. It was found that the supported PW catalysts exhibited high activity, but their reusability was very poor due to the severe leaching of heteropoly anions into water. On the contrary, supported Cs salt of PW catalysts showed high conversion and selectivity with high water-tolerance. The dealuminated USY was revealed to be the suitable support for cesium salt of PW. Catalytic activity was discussed in relation with the surface area and acid strength of catalysts.