Decomposition of NO on Pd and Ir. Comparison with Pt and Rh

Abstract

The unimolecular decomposition of NO has been examined on Pd and Ir and they are compared with the corresponding reactions on Pt and Rh. The runs were carried out in a differential now reactor, at pressures from 0.01 to 5 Torr and temperatures from 500 to 1800 K. It was found that all rates of product formation could be described by Langmuir-Hinshelwood unimolecular rate expressions, with an accuracy of +/- 20% under all conditions. The decomposition of NO was virtually identical on Pt and Pd, and on Rh and Ir, but varied widely with temperature between these two groups of metals.