Supported Keggin type heteropolycompounds for ecofriendly reactions

LUIS RENE PIZZIO; G VAZQUEZ, PATRICIA; V CACERES, CARMEN; N BLANCO, MIRTA

APPLIED CATALYSIS A-GENERAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2003 vol. 256 p. 125 - 125

0926-860X

New supported Keggin heteropolyacid (HPA) catalysts were prepared in order to make a contribution to the field of catalyzed acid reactions by means of ecofriendly technologies. The esterification of isoamyl alcohol and acetic acid in gaseous phase was studied using tungstophosphoric acid (TPA) supported on different carriers, silica materials, carbon and alumina. These catalysts were characterized by FT-IR, DRS, TPR and their acidity was evaluated through the isopropanol dehydration test reaction. The higher acidic catalysts prepared with silica materials led to the greatest activities due to the higher proton availability which, in turn, was related to the lower interaction and dispersion of the active species. In order to perform this acid reaction in heterogeneous liquid phase and to avoid the tungstophosphoric or molybdophosphoric acid (MPA) solubilization during reaction, functionalized silica and SiMCM-41, and polyvinyl alcohol hydrogel?polyethylenglycol (PVA-PVG) beads were used as new supports. The physical?chemical characterization of the supported catalysts by FT-IR, XRD, Full-size image (