Cardo polyimide membranes for CO2 capture from flue gases

Publisher Summary This chapter discusses that cardo polyimide hollow fiber membranes were developed as an alternative to existing commercial amine absorption for CO 2 capture from flue gases. To investigate the relationship between chemical structures and CO 2 separation properties, various cardo polyimides were synthesized to measure CO 2 separation properties and some chemical structure was found to give remarkable properties both in CO 2 permeation and selectivity. An economic analysis was carried out for CO 2 separation using the hollow fiber membrane followed by a liquefaction process. In the cost breakdown of CO 2 separation with membrane, the electricity consumption of the vacuum pump, which induce a pressure difference between a feed side and a permeate side of a membrane, contributed 50% or more of the total cost. For further cost reduction, an application of membrane system to pressurized gas streams similar to CO 2 removal from natural gas might be a promising way of reducing the cost of CO 2 separation.