Structural and Catalytic Activity of V 2 O 5 -Supported on AlPO 4 Catalysts (original) (raw)

A series of AlPO 4-V 2 O 5 (APV) systems with various vanadia amounts 1-30 mol% were prepared by the impregnation method and calcinated at 400 and 600 C for 4 h. The catalysts were characterized by TG=DTG, DSC, IR spectroscopy, XRD, N 2 adsorption, and electrical conductivity measurements. The surface acidity and basicity of the catalysts were studied by the dehydrationdehydrogenation of isopropyl alcohol and the adsorption of pyridine. The catalytic gas phase esterification of acetic acid with ethyl alcohol was carried out at 210 C in a flow system at 1 atm using air as a carrier gas. The results showed that the catalysts calcinated at 400 C were active and selective towards the formation of ethyl acetate whereas the calcination of samples at 600 C led to a drastic reduction in both activity and selectivity. Good correlations were obtained between catalytic activities towards ester formation and acidity of the prepared catalysts.