Intrinsic kinetics of the methanol dehydration to dimethyl ether over laboratory and commercial γ‐alumina: a comparative study

Abstract

The intrinsic kinetics of the methanol dehydration to dimethyl ether over the laboratory-synthesized and commercial γ-alumina is studied. A set of kinetic models admitting different mechanisms of the reaction is developed. The developed kinetic models, as well as the kinetic models of the methanol dehydration presented in the literature, are experimentally verified. It is shown that the kinetic model admitting Langmuir-Hinshelwood mechanism with associative methanol adsorption is the only model which describes intrinsic methanol dehydration rate over either laboratory or commercial γ-alumina catalyst. The estimated activation energies are 121 and 128 kJ/mol, methanol adsorption heats are 45 and 70 kJ/mol, and methanol adsorption entropies are 72 and 131 J/(mol  K) for the laboratory and commercial samples, respectively. The laboratory-synthesized γ-alumina may be successfully used for modeling and scaling the process that utilizes the commercial γ-alumina catalysts.