Estimation of O-2 and CO2 solubility in microbial culture media

A simple model for predicting gas solubilities of O-2 and CO2 at low pressu re and near ambient temperature in solutions of salts, sugars, and organic solvents (alcohols, ketones, ethers, aldehydes, etc.) is proposed. It is de rived from the Van Laar assumptions and takes account of size differences b etween molecules in solution by their volumetric fraction. It is a group co ntribution model where anions and cations are considered as groups and othe r molecules are treated as in the UNIFAC (UNIQUAC Functional group Activity Coefficients) procedure. Pseudo-Henry's constants for groups were determin ed using solubility data in aqueous solutions containing only one salt, one sugar, or one organic compound at 25 degrees C. The predictive performance of the model was evaluated by comparison with experimental data using mult icomponent aqueous salt-sugar mixtures. The model was used to estimate solu bilities of oxygen and carbon dioxide in fermentation media.