Development of CO2 separation membranes (1) -: Polymer membrane

With the aim of developing technologies for separating and recovering CO2 from exhaust gases of stationary CO2 emission sources amid the ongoing problem of global warming, we developed a new cardo type polymer membrane. The cardo type polymer has a molecular structure with a bulky loop form. The polymer shows the important characteristics of a high gas permeability and high solubility in organic solvents that provide hollow fiber membrane processability and heat stability derived from an aromatic structure. Since a cardo type polyimide showed the highest CO2/N-2 selectivity and CO2 permeability during the screening of many newly synthesized cardo type polymers, we selected it and conducted a structure function relationship analysis looking at CO2/N-2 selectivity and CO2 permeability. We identified new cardo type polyimide structures for CO2 separation. Then, we developed the wet spinning technology to produce an asymmetric hollow fiber membrane, and incorporated the membrane in module. In addition to using bench-scale testing to obtain basic data for implementing the module, we considered a 1,000MW coal combustion power plant. The information obtained confirmed that in energy terms, the developed membrane separation method is superior to current methods.