The kinetics of ethane hydrogenolysis over cobalt catalysts supported on silica has been investigated. The results compare well with previous data from Sinfelt et al., Haddad and Goodwin, and Babernics et al. The data were found to be characterized by an isokinetic temperature, T-iso = 490+/-40 K and it was therefore possible to apply the model of selective energy transfer (SET). This approach indicates that either there is an energy transfer from the catalyst by full resonance to a vibration mode of the reactant with v = 680 cm(-1) corresponding to a metal (M)=CH2 bond, or there is an energy transfer to an M-CH3 vibration mode in the region of 400 cm(-1), most likely at 355 cm(-1). In any case, these interpretations indicate that it is the breaking of one or two metal-carbon bonds that determine the reaction, not the cleavage of the carbon-carbon bond of ethane. This is in agreement with recent views of Sinfelt. (C) 2002 Elsevier Science B.V. All rights reserved.