OXYGENATION OF HYDROGEN SULFIDE IN SEAWATER AT CONSTANT SALINITY, TEMPERATURE, AND PH

The kinetics of the reaction between sulfides and oxygen in seawater (S = 30.27%) at 9.8° C. are described. The rate of change of concentrations of total sulfide, oxygen, thiosulfate, sulfite, and pH were determined. Total sulfide, thiosulfate, and sulfite were determined colorimetrically, oxygen chromatographically, and pH electrometrically. The reaction is complex, as indicated by the variety of products, but the temporal course of the reaction generally follows mixed second-order kinetics after the first few hours of the reaction. The apparent rate constants for oxygen and total sulfide were 1.5 × 10-3 and 0.5 × 10-3 (μg.-atoms per liter)-1 (hr.)-1 in the concentration ranges investigated. The major reaction products were thiosulfate and sulfate, with sulfite occurring as an unstable but fairly long-lived intermediate product. The reaction rate decreases as the solid surface area increases. © 1969, American Chemical Society. All rights reserved.