The kinetics of CH3NH2 decomposition on polycrystalline nickel foils a
re examined over a wide range of catalyst temperature, pressure, and g
as composition in a steady-state flow system with conversions sufficie
ntly low that differential rates are obtained. Rate data obtained in p
ure CH3NH2 can be fit accurately by a Langmuir-Hinshelwood (LH) unimol
ecular rate expression. Hydrogen alters the decomposition rate to a hi
gher value which is independent of P-H2 and can also be fit by a LH un
imolecular expression. Results are interpreted as that with the presen
ce of H-2 the methylamine decomposition on nickel proceeds through a p
recursor intermediate. No data points deviate from calculated LH curve
s by more than 15% over a range of 10(3) in reaction rates.