Dibutyl Sulfide: Synthesis, Pd, Pt Extraction and Separation Studies

Dibutyl sulfide (abbreviated as M) was synthesized with Na2S·9H2O and n-butyl bromide. The performance for extraction and separation of palladium and platinum was studied and the optimum conditions for separation of Pd and Pt were 0.344 mol·L-1 for dibutyl sulfide, 1∶1 for Organic/Aqueous phase ratio(O/A), 6 min extraction and 2 mol·L-1 H+ in aqueous phase as obtained by rhombic experiments. The capacity of palladium extraction was determined with dibutyl sulfide to be exceeded 17 g·L-1. The possible mechanism of palladium extraction with dibutyl sulfide was also studied. The extraction equation was ascertained and signified as PdCl42- + 2M → PdCl2·2M + 2Cl-. Palladium could be stripped effectively by ammonia of 9 mol·L-1, and the palladium stripped was 96.3%. Platinum could be stripped by sodium chloride, the percentage stripping of platinum was 88.9% when concentration of sodium chloride was 12 g·L-1. The optimum conditions of separating palladium and platinum were verified with mixed solution containing [PdCl4]2-, [PtCl6]2-, Cu2+, Fe2+ and Ni2+.