Original Articles: 2014 Vol: 6 Issue: 6
Solvent extraction of palladium(II) with 2-hexyl-5-methyl benziminazole sulfide
Abstract
A new extractant of 2-hexyl-5-methyl benziminazole sulfide (HMBMS) was synthesized and used in the extraction of Pd(II) from hydrochloric acid solution. Pd(II) was extracted quantitatively with HMBMS in kerosene. Thiourea solution could be used as stripping agent. Extraction parameters of Pd(II), including 2-hexyl-5-methyl benziminazole sulfide (HMBMS) concentration, contact time of aqueous and organic phases, organic/aqueous (O/A) phase ratio and hydrochloric acid concentration of aqueous phase, were studied in detail. The extraction saturation capacity of Pd(II) was determined from 0.1mol L-1 HCl solution with 30% (v/v) HMBMS and its experimental value exceeded 10 g L-1 under the experimental conditions. Pd(II) and Pt(IV) could be separated effectively and the separation coefficient of Pd(II) and Pt(IV) (βPd/Pt) reached 1.5×104 when HMBMS and HC1 concentration were fixed at 20% (V/V) and 0.1 mol L-1, respectively. Stripping of Pd(II) from loaded organic phase was performed using thiourea solution