Oxidation of simple compounds and mixtures in supercritical water: carbon monoxide, ammonia and ethanol

The oxidative reaction kinetics of dilute carbon monoxide, ammonia and ethanol were determined both individually and in mixtures in supercritical water. Under supercritical conditions (temperatures above 374C and pressures above 22.1 MPa) water behaved as a dense gas with high solubility for organics and oxygen and was therefore an excellent environment in which to oxidize hazardous organic materials with no char formation. Empirical expressions for the oxidation of carbon monoxide and ethanol are presented, both being partially oxidized in the absence of molecular oxygen in supercritical water. Ammonia was difficult to oxidize between 400-540C, the operating temperature range of the isothermal plug-flow reactor used. Ethanol did not significantly alter the oxidation rates of ammonia or carbon monoxide under the experimental conditions.