Kinetics of Sulfide Oxidation by Dissolved Oxygen

The kinetics of sulfide oxidation by dissolved oxygen in three domestic wastewaters containing concentrations between 0.2 and 8 mg/L sulfide and 5 and 20 mg/L oxygen were studied. The reaction order with respect to sulfide varied with sulfide concentration but was approximately first order for two of the wastewaters and significantly less for the third. The reaction order with respect to oxygen could be described by Michaelis-Menton kinetics, with K = 3 mg/L. Chemical and biological components of the oxidation process were significant over the concentration range studied. The effect of temperature on the rate constant was well described by the Arrhenius equation. Rate constant data for 14 wastewater samples are presented and the implications of variability in this data are discussed.