Formation of glyoxyloxyl chloride, HC(O)C(O)Cl, in the gas-phase oxidation of trichloroethene by NO2

Abstract

Within the temperature range 303–416 K, the main products of the gas-phase oxidation of trichloroethene by NO₂ are nitrosyl chloride, ClNO, and glyoxyloxyl chloride, HC(O)C(O)Cl. Glyoxyloxyl chloride has been isolated by fractional condensation and identified by its infrared spectrum and molecular weight determination. It decomposed above 416 K into CO and HCl and was hydrolysed in the presence of water vapour to give glyoxylic acid, HC(O)C(O)OH. The values of the reaction rate constants for the consumption of NO₂ were 9.9 ± 3 × 10^–4 and 2 ± 1 × 10^–3 dm³ mol^–1 s^–1 at 343.1 and 362.2 K, respectively. A reaction sequence is proposed to explain the formation of HC(O)C(O)Cl.