Oxygen solubility modeling in inorganic solutions: concentration, temperature and pressure effects

A model has been developed to predict and estimate the P-O2 and T-dependent molal solubility, (c(aq))(1), Of oxygen in aqueous solutions containing an inorganic solute, I. It is based on the concept that (c(aq))(1) may be obt ained by multiplying the thermodynamics-based P-O2 and T-dependent equation for the molal solubility of oxygen in pure water, c(aq), by a factor (phi- factor) that is < 1 and which is functionally dependent only upon the molal concentration, C-1, of I. The C-1-dependent phi-functions of 21 different I's have been determined from an analysis of published solubility data. Sub sequently, the (c(aq))(1)/P-O2 ratios for several solutions, containing sin gle and multiple I, were predicted for a wide range of T by combining the c orresponding phi-function with the thermodynamics-based equation for pure w ater. Tnt: predicted ratios were compared with available published data rel ating to effects of T. Satisfactory agreement was found between the predict ed and experimental behavior, thereby validating the general principles of the model. It is anticipated that the model will be provide a foundation fo r predicting and estimating oxygen solubility under widely different hydrom etallurgy leaching conditions, ranging from bio-leaching processes to oxyge n pressure leaching. (C) 1998 Published by Elsevier Science B.V. All rights reserved.