High-performance Cr/H-ZSM-5 catalysts for oxidative dehydrogenation of ethane to ethylene with CO2 as an oxidant

Cr/H-ZSM-5 (SiO2/Al(2)O(3)greater than or equal to190) catalyst effectively dehydrogenated ethane to ethylene in the presence of CO2 oxidant. The maximum rate of formation of ethylene at 923 K was 0.516 mmol g-catalyst(-1) min(-1) and selectivity was over 90%. Carbon dioxide maintained the activity of the catalyst by removing coke from the surface of the catalyst. TPR profiles of the Cr/H-ZSM-5 catalysts suggest that there are high oxidation states Cr species such as Cr(VI) on the catalyst, which is considered key of higher activity. (C) 2002 Elsevier Science B.V. All rights reserved.