Dehydrogenation of isobutane in the presence of a Zr 2Fe hydrogen acceptor

Abstract

Earlier it was shown that the isobutene yield during dehydrogenation of isobutane on Pt/AI203 at temperatures ranging from 300 to 400C can be increased by shifting the thermodynamic equilibrium of the reaction through the removal of the hydrogen formed by hydride-forming metals Ti and Zr [1] and intermetallic compounds ZrNi and ZrCo [2]. However, the isobutene yields obtained in these conditions did not exceed 10-11 mol.% and were dictated by the kinetic and thermodynamic limitations of the adsorption capacity of the metals and intermetallic compounds tested, and also by the reduction in the stability of the aluminaplatinum catalyst when hydrogen is removed from the reaction flow. In the present study, an oxide chromium catalyst was used as the isobutane dehydrogenation catalyst. This is less sensitive to the presence of hydrogen in the reaction mixture than platinum catalytic systems. IntermetaUic compound Zr2Fe, which is capable of absorbing hydrogen at temperatures above 400C [3], was tested as the hydrogen acceptor.