Perturbation of steady-state catalytic dehydration of alcohols by pulses of water and other substances

Abstract

The dynamic behaviour of systems consisting of 2-propanol or tert-butanol and of a solid dehydration catalyst has been studied by means of pulses of the alcohols, water, nitrogen or carbon dioxide, respectively, introduced onto fresh catalyst surface in a stream of nitrogen, or onto the working surface. The catalysts employed were alumina, alumina modified by fluoride, sulphate or sodium ions, respectively, thoria, silica-alumina, phosphotungstic acid and a sulphonated styrene-divinylbenzene copolymer. The positions and shapes of the response curves allowed to distinguish between catalysts operating by formation of surface alkoxides or of protonated alcohols as surface intermediates in the transformation of the alcohols into alkenes.