Polymer membranes for hydrocarbon separation and removal

The present review deals with the problem of hydrocarbon separation and removal using polymer membranes. It is demonstrated that the use of membranes based on stiff chain glassy polymers for separation of olefins and paraffins as well as aromatic, alicyclic, and aliphatic hydrocarbons is quite effective. Selective permeability in all applications based on glassy polymers is dominated by the diffusion component. Separation efficiency can be increased by modifying the structure of the polymer and introducing active groups or additives into the polymer that change sorption and diffusion properties of the system. Application of membranes based on rubbery polymers for selective removal of hydrocarbon vapors from their mixtures with air as well as for selective removal of hydrocarbons from their aqueous solutions, is considered. The effect of the chemical composition of rubbery polymers on their permeability to hydrocarbons is analyzed. (C) 2004 Elsevier B.V. All rights reserved.