REMOVAL OF CO2 BY GAS-ABSORPTION ACROSS A POLYMERIC MEMBRANE

For the purpose of removing carbon dioxide from flue gases a novel operation, "permabsorption", a hybrid operation of membrane permeation and gas absorption was proposed. Permeability of a non-porous hollow-fiber (HF) membrane made of polydimethylsiloxane for pure CO2 and O2 was obtained in this simple-operation mode, the observed values being in reasonable agreement with literature values. High permselectivity can be attained by using an appropriate absorbent liquid. In the permabsorption of CO2 using alkaline solution, the permeation rate could be expressed by a model based on membrane permeation with gas absorption. The performance of a multiple-HFs module was comparable to that of a packed column. This result implies that the permabsorption method provides the possibility of operation at lower liquid flow rate than in packed columns and, therefore, of energy-saving CO2 removal from flue gases.