To facilitate design of an extraction process for removal of organic solutes from petroleum and petrochemical waste streams distribution-coefficient date were obtained for typical organic pollutants at high dilution. Volatile solvents were chosen because of their low solubility in water and because they are recovered easily. Samples form both the aqueous and the organic phase were analyzed chromatographically. To remove a sample from an equilibrium cell operating at ressures well above atmospheric, a special technique was developed using low-melting Indalloy for micro-encapsulation.
Distribution coefficients at ambient temperature are given for a variety of solutes, including esters, phenolics, ketones, and aldehydes. The results are correlated by a simple relation based on perturbed-hard-sphere theory for dilute solutions. Isobutane or isobutylene may be particularly useful in a dual-solvent extraction process wherein a polar organic solvent is used in a secondary extraction tod remove the polar solvent from water.