Study Of 12-Tungstophosphoric Acid Supported On Mesoporous Silica And Its Catalytic Performance

12-Tungstophosphoric acid was supported on SBA-15 and amine-modified SBA-15 by impregnation and direct synthesis . The structure and properties of the catalysts were characterized by FT-IR, XRD, N2 adsorption-desorption, TEM, and NH3–TPD. And the catalytic activity, selectivity and reusability was evaluated by catalytic synthesis of fructone.A series of different loading of catalysts expressed as HPW/SBA-15 were prepared by impregnating SBA-15 with HPW, and were characterized by FT-IR, XRD, N2 adsorption-desorption, TEM, and NH3–TPD. The result showed that the Keggin structure of the heteropolyanions was Maintained, but the Acid of the catalysts was reduced. And the BET surface area, pore volume and pore diameter decreased beacause the tungstophosphoric acid entered the pore, and in the high-loading amount aggregation occurred. The catalysts exhibited excellent catalytic activity and selectivity except for reusability, and the reaction conversion dropped to 30% after reused for six times.Templates were Removed by calcination and extraction, and the prepared SBA-15 was modified by APTES, and 12-tungstophosphoric acid was supported on amine-modified SBA-15 by impregnation. The structure and properties of the catalyst were characterized by FT-IR, XRD, N2 adsorption-desorption, TEM, and NH3–TPD. The result showed that the Keggin structure of the heteropolyanions was maintained and the tungstophosphoric acid dispersed highly. The surface of SBA-15 prepared by extracting template contains more silanol groups and can combine more amino and phosphotungstic acids. The catalysts exhibited excellent reusability but low activity beacause the acidity of the catalysts were reduced.SBA-15 ordered mesoporous silica materials containing of HPW heteropoly acid were synthesized via involving HPW in the SBA -15 synthesis process. The results of FT-IR, XRD, N2 adsorption-desorption, TEM, and NH3–TPD showed that the Keggin structure of the heteropolyanions was maintained and the tungstophosphoric acid dispersed highly. The catalysts maintained the ordered mesoporous structure in the low-loading amount, but the ordered structure damaged in the loading amount of 33.3%. The catalysts exhibited excellent catalytic activity, selectivity and reusability, and the reaction conversion reached up to 80.3% after reused for six times.