Recent Development of Enhanced Polymeric Blend Membranes in Gas Separation: A Review

Natural gas is the most rapid growing energy sources around the world. The presence of CO2 in natural gas lowers its calorific value and purification of a natural gas by removing CO2 is an essential process to increase its value. Several separation technologies are used to remove acidic gases like H2S and CO2 from natural gas. Among these technologies, membrane process is a feasible energy saving alternate to CO2 capture. The three types of membrane include polymeric, inorganic and mixed matrix membranes. Currently, polymer membranes and inorganic membranes were considered for gas separation, but inorganic membranes are too costly. Even mixed matrix membrane performance suffered defects caused by poor glassy polymer and particle interactions. Pure glassy and pure rubbery are problematic due to their instructive properties. The blending of glassy with rubbery polymers improve membrane properties for gas separation. To enhance the compatibility of the polymer blend, a third component is added such as alkanol amines. Although, the enhanced polymeric blend membranes have many advantages in terms of permeance, selectivity, thermal and chemical stability. Polymer blending also offers an effective technique to synthesize membranes with desirable properties.