Reaction and Deactivation Rates of Methane Catalytic Cracking over Nickel

The kinetics of methane catalytic cracking over nickel Supported on porous and nonporous aluminas Was modeled using, a separable kinetics approach in order to develop :initial rate and activity decay,equations. The model parameters were estimated using a set of experiments conducted in an electrobalance. The experimental Work covered the 500-650 degrees C temperature range, using pure methane, as well as different partial pressures of CH(4)/N(2) and CH(4)/H(2) mixtures at atmospheric: The model results showed a good match with the experimental data, and the estimated kinetic parameters agreed well with those :reported in the literature. The morphology of the support affected the initial reaction rate and catalyst deactivation. The methane cracking activation energy was estimated to be 88 and 75 kJ/mol for the porous and nonporous catalysts, respectively. The activation energy for the encapsulating carbon formation was estimated to be 147 and 149 kJ/mol for the porous and nonporous catalysts, respectively. The deactivation reaction was found to be half order in surface carbon. The model was expanded to include cracking/regeneration cycles; The model showed good agreement with the experimental data at different experimental conditions and up to 39 cycles. cracking/regeneration cycles suggest that the porous catalyst can be used for conducting continuous methane cracking.