THE PHOTOLYSIS OF ISOCYANIC ACID VAPOR

Abstract

The photolysis of isocyanic acid vapor has been studied at temperatures ranging from −31 to 200 °C, and pressures from about 2 to 200 mm. Products identified were CO and N2 in a ratio which varied from 2.5 to 5, together with much smaller amounts of hydrogen. The mechanism[Formula: see text]accounts approximately for the products of the photolysis at low HNCO pressures and low temperatures. Additional reactions of NCO radicals with HNCO are postulated to account for increased production of CO and N2 as the temperature and HNCO pressures were increased.The effects of adding ethylene and hydrogen to the system were briefly investigated. The results are explained in terms of reactions of NH and NCO radicals with hydrogen and ethylene.