EXTRACTION OF Zn AND Cd FROM CHLORIDE LIQUORS BY TRI-n-BUTYL PHOSPHATE

摘要

Studies have been made on the extraction of Zn and Cd by TBP（tri-n-butyl phosphate）from diluent hydrochloric acid solutions of soldium chloride.The experiments show that thespecies extracted from diluent HCI solutions of NaCl appear to be predominantly ZnCl₂·2TBP and CdCl₂·2TBP.For Cd,at lower acidities,anionic complexes of the typeH₂CdCl₃ are also extracted.As the acidity is increased,H₂CdCl₄ appear to be predominantcomplexes in organic phase.For Zn,the acidocomplexes of the type HZnCl₃ appear in organ-ic phase after the acidity of solutions reaching a certain value（[HCl]0.1 mol/L）.Furthermore,the ultraviolet absorption spectra of both aqueous and organic phases have beenstudied,and the infrared spectra of the organic phases have been exomined.The extractionmechanism and temperature effect are also discussed.