Kinetic Study of Nitric Oxide Decomposition over Particles under Pressure

The reaction rate constants of nitric oxide decomposition over calcium oxide, calcium sulphate, silica sand and char were measured using a fixed-bed reactor at a pressure of 788kPa and temperatures from 500 to 875°C. Calcium oxide, which was produced by calcining limestone, promoted the decomposition of nitric oxide. Calcium sulphate and silica sand were almost inert. The catalytic activity of the decomposition of nitric oxide over calcium oxide became greater as total pressure became higher. The decomposition of nitric oxide over char and calcium oxide was firstorder with respect to nitric oxide concentration. At 860°C and 788kPa, the reaction rate constants of nitric oxide decomposition over char and over calcium oxide were 18.9 (s-1) and 1.3 (s-1) respectively.