Membrane technologies for the storage as methane of energy generated by wind power and other renewable sources

In the last years, membrane systems have found application at industrial level in a large variety of advanced separation and purification processes, including biofuels' production and purification. The numerous advantages over conventional techniques can be summarized as: minimization of the capital cost, flexibility, the compactness of the plants, and optimal ratio between productivity and efficiency along with energy-saving. In this chapter a general overview of the concept of membranes and membrane technology is given, which is followed by information on membrane classification and techniques of fabrication. The remaining sections then discuss gas separation, pervaporation and inorganic membrane reactor-based transport mechanisms and the use of these membrane processes for biofuel production and purification (including hydrogen production).