Pervaporation is a membrane separation process that is based on an energy-efficient combination of permeation and evaporation. It is applied to the removal of volatixle compounds out of solutions through a selective membrane. By creating a vacuum or introducing a flow of purge gas on one side of a dense membrane, volatile compounds in a liquid flow diffuse through the membrane. By using selective membranes, pervaporation can be applied to the dehydration of organic solutions as well as to the removal of organic contaminants in an aqueous solution. In addition to its high energetic efficiency, due to the use of a dense membrane pervaporation is not subjected to azeotropic limitations.