抄録
Copper was extracted by LIX84I-Shellsol 71 solution from a dilute aqueous solution with a five-stage mixer-settler extraction column. The effective removal of copper could be achieved by extraction with the multi-stage extraction column. The reaction rate of copper extraction by LIX84I was measured with a flat interface stirred vessel, and the rate is found to increase significantly by purification of the extractant. Simulation of the multi-stage counter-current extraction was carried out using the specific interfacial area determined from the dispersed phase holdup and the dispersed drop size. The mass transfer coefficients in the continuous and dispersed phases are estimated on the basis of the mass transfer around and within the rigid sphere. The simulated results agree with the observed ones when the reaction rate with the purified extractant is used. This indicates that the effect of surface active impurities on the extraction reaction rate might be reduced with an increase in the specific interfacial area. The simulation suggests that extraction with a high concentration of the extractant is effective for copper removal, but the effect of mass transfer resistance within the aqueous phase cannot be neglected with the increase in extractant concentration.
