CONVERSION OF 2-PROPANOL OVER CHROMIUM ALUMINUM ORTHOPHOSPHATES

The catalytic conversion (dehydration/dehydrogenation) of 2-propanol o n a series of CrPO4-AlPO4 (CrAlP) catalysts, which were differently pr epared and thermally treated at 773-1073 K, has been studied by microc atalytic pulse reactor technique at different temperatures (473-573 K) . Kinetic parameters for conversion of 2-propanol to propene have been obtained by analysis of the data through the Bassett-Habgood equation for first-order reaction processes. The influence of the reaction tem perature upon alcohol conversion and product selectivities was also in vestigated. Catalytic performance was affected by the precipitation ag ent. Catalysts obtained in propylene oxide-aqueous ammonia showed the highest activity towards propene compared to other catalysts. Calcinat ion at increasing temperatures caused a decrease in the activity due t o the decrease in surface acid character. The results of dehydration t o propene can be well interpreted through the differences in the numbe r and strength of acid sites, which were gas-chromatographically measu red using pyridine and 2,6-dimethylpyridine chemisorbed at different t emperatures (573 and 673 K). Dehydrogenation to 2-propanone occurred t o a small extent at all reaction temperatures and, besides, its conver sion changed slightly with reaction temperature. Propene selectivity s trongly increased with increasing reaction temperature.