화학공학소재연구정보센터
Journal of Membrane Science, Vol.95, No.1, 63-69, 1994
High Collection Rate of Pd in Hydrochloric-Acid Medium Using Chelating Microporous Membrane
An iminodiacetate (IDA) group was introduced onto a microporous hollow-fiber membrane while maintaining the permeation flux of the original membrane. A 20 g/m3 Pd/palladium chloride solution, with pH ranging from 0.5 to 4 with hydrochloric acid addition, was forced to permeate through the chelating microporous hollow-fiber membrane with a thickness of 0.9 mm. The higher permeation rate of the Pd solution led to a higher sorption rate because of negligible diffusional mass-transfer resistance. In the subsequent elution of Pd sorbed onto the membrane, the convective transport of Pd ions due to permeation of HCl as an eluent produced a lower degree of tailing in the elution curve, resulting in a higher enrichment of Pd. For comparison, a similar procedure was performed with a bed charged with the IDA-group-containing beads. Convection-aided separation using the chelating microporous membrane was superior to diffusion-limited separation using the chelating-bead-packed bed with respect to sorption and elution rates.