Pervaporation

Typical hydrophilic pervaporation membrane materials fall into two categories: the polymer material and inorganic material. The former material is easier to prepare various module membranes and the strength of produced membranes is higher. The latter one is also able to be designed in various shapes, with a range of average pore sizes and permeability, and excellent for high-temperature membrane operations. This chapter discusses the relationship between the structure characteristics of pervaporation membrane materials and their separation performance. It also discusses the permeability and permselectivity for aqueous volatile organic compounds (VOCs) solutions through their graft copolymer membranes in pervaporation, from the viewpoint of their membrane structure, and analyses permselectivity by the solution-diffusion theory. The chapter presents the structure characteristics, modification methods and pervaporation performance of ethanol permselective membrane materials with separation priorities. It further discusses the permeation and separation mechanism of benzene-cyclohexane mixtures through Butyrylcellulose (BuCell) membranes by pervaporation on the basis of the solution-diffusion model.