Abstract: Insoluble gases, liquid and solid materials present as the disperse phase in a heterogeneous dispersion are removed by contacting such dispersion with one side of a membrane in which the disperse phase is soluble and on which the disperse phase coalesces and contacting the other side of the membrane with a material which does not permeate or react with the membrane but which reacts with the disperse phase passing through the membrane. The reaction product is such that it does not permeate the membrane. In this manner the driving force for passage through the membrane by the disperse phase is maximized.