Investigate the permeability properties of polyether urethane and polyester urethane membranes in gas separation process of carbon dioxide/nitrogen

The increasing concentration of the carbon dioxide greenhouse gas in the atmosphere has caused the concern and pressure of the international community to reduce and control for emissions of the gas. The separation of carbon dioxide attracted considerable attention in recent years in order to control its dissemination in the waste gases and exhaust gases of chimneys. In this regard due to the advantages of membrane technology in gas separation, the permeability properties of a new type of polyurethane membrane have been evaluated and compared on two basis of polyether poly tetra methylene glycol polyester poly caprolactone. Membranes were made by using the method of casting solution and the differential scanning calorimetry technique has been used to determine the thermal properties and glass transition temperature of membranes. As well as, permeability and selectivity properties of membranes were examined by helping the throughput test of pure gases. Experiments were carried out at different pressures in temperatures of 25 ° C. Based on the test results, the permeability of carbon dioxide gas and nitrogen gas decreased with increasing the pressure on both types of membrane, and selectivity of the carbon dioxide to the nitrogen increased. Also the polyether-based membrane was introduced as superior membrane for gas separation of carbon dioxide/nitrogen in the comparison between two types of membrane according to the Robson curve.