Conversion of Alcohols (α-Methylated Series) on AlPO4 Catalysts

Article abstract of DOI:10.1006/jcat.1995.1032

The conversion (dehydration/dehydrogenation) of alcohols in α-methylated series (methanol, ethanol, 2-propanol, and tert-butanol) on AlPO4 catalysts differently prepared has been studied by microcatalytic pulse reactor technique at different temperatures and flow rates.The kinetic parameters have been obtained by analysis of the data through the Basset-Habgood equation.Dehydration to ether and/or olefin is the major reaction process.Dehydrogenation product was only scarcely found in 2-propanol conversion.The influence of the reaction temperature upon the conversion of alcohols and the selectivities of the products was investigated.Activities increases as a function of surface acidity of the AlPO4 catalyst as well as with the α-substitution in the alcohol.Moreover, selectivity studies indicated that ethanol and 2-propanol dehydration follows a combination pathway of parallel and consecutive reactions.A good correlation between the results of dehydration conversion and acid properties, gas-chromatographically measured through the irreversible adsorption of pyridine (473 and 573 K) and 2,6-dimethylpyridine (573 K), is observed.Also, activity poisoning results indicated that Broensted acid sites of AlPO4 catalyst participated in dehydration processes, thus strengthening the carbenium ion reaction pathway in AlPO4 catalysts.