THEORIES OF INHIBITION BY NITRIC OXIDE

Abstract

Theories of the inhibition by nitric oxide of pyrolysis and other reactions, proposed by Voevodsky, by Wojciechowski and Laidler, and by Norrish and Pratt, are critically discussed in this paper with reference to the experimental results. The Voevodsky scheme, involving the suppression by nitric oxide of a heteorgeneous initiation process, is shown to be inconsistent with the observed results for ethane pyrolysis. The Norrish–Pratt scheme, involving oxime formation and NO-induced oxime decomposition, is shown to be unsatisfactory in failing to predict nonintegral orders and in leading to activation energies that are much too high. It is concluded that it is necessary to postulate H abstraction by NO, as in the Wojciechowski–Laidler mechanisms.