Supercritical <Emphasis Type="Italic">n</Emphasis>-butane isomerization

Supercritical n-butane isomerization over the solid acid catalysts sulfated zirconia, TiO₂-supported H₄Si(W₃O₁₀)₄] · xH₂O (Keggin-type heteropoly acid), and H-mordenite is studied in a flow reactor. The critical parameters of n-butane are calculated for a wide range of reaction conditions. Changing from gaseous n-butane to supercritical n-butane markedly extends the lifetime of the catalysts. Under supercritical conditions, the activity and selectivity of the catalysts are invariable, provided that the density of the reaction mixture is in the vicinity of the critical density of n-butane. After the catalysts are deactivated in the gas medium, they can be partially or completely reactivated in the supercritical fluid.Translated from Kinetika i Kataliz, Vol. 45, No. 6, 2004, pp. 942–946.Original Russian Text Copyright © 2004 by Bogdan, Klimenko, Kustov, Kazanskii.