Ethane hydrogenolysis catalyzed by W(100)

Abstract

The ability of the (100) face of tungsten to catalyze ethane hydrogenolysis has been investigated. At 573 K, methane is formed with a specific activity of 0.01 molecules per surface tungsten atom per second (100 Torr H 2, 1 Torr C 2H 6), with no evidence of catalyst deactivation even after several hundred turnovers. Hydrogenolysis is approximately first-order in ethane and half-order in dihydrogen, and displays an apparent activation energy of 27 kcal/mol. Negligible activity is displayed by clean tungsten; the true catalyst appears to be a monolayer of carbide which is formed on the surface of the tungsten on exposure to the reactants.