Theoretical and experimental study of palladium(II) extraction from hydrochloric acid solutions into Aliquat 336/PVC membranes

The extraction of palladium(II) from its hydrochloric acid solutions into p oly(vinyl chloride) (PVC)-based membranes containing Aliquat 336 chloride a s both the extractant and the plasticizer was experimentally studied. The r esults showed that these membranes extracted palladium(II) rapidly and to a very high degree. This property can be used either for the analytical dete rmination of trace levels of palladium(II) or for the recovery of this prec ious metal from industrial wastewaters and hydrometallurgical solutions, A mathematical model for the palladium(II) extraction into an Aliquat 336/PVC membrane which takes into account the interfacial palladium(II)-Aliquat 33 6 chloride reaction and the diffusion mass transport through the membrane w as developed, The model was fitted to the experimental extraction data to d etermine the values of the relevant physicochemical constants (i.e. diffusi on coefficients and kinetic rate constants). (C) 2000 Elsevier Science B.V. All rights reserved.