Membrane processes and postcombustion carbon dioxide capture: Challenges and prospects

The possible place and role of different membrane processes for post combustion carbon dioxide capture are reviewed and discussed. In a first step, the interest and limitations of membrane contactors in order to achieve intensified CO2 absorption in a chemical solvent are briefly exposed. Membrane based separation processes are presented and discussed in a second step, with two major strategies: low selectivity, high permeability materials which require multistage processes, and chemically reactive, high selectivity membrane materials which could possibly achieve the target CO2 capture process in a single stage. A special emphasis is put on materials and design challenges. Unexplored issues (target CO2 purity, cost curves, hybrid processes, role of water, minor components) are finally exposed as major research targets.