Tributyl phosphate（TBP） was employed for the Bi（Ⅲ） extraction from hydrochloric acid medium.The effects of extraction time and material concentration were examined.The replacement mechanism between the anion（Cl-） and TBP was proposed for extraction.The results show the species extracted into the organic phase were found to be mainly BiCl3·x TBP（x=2 or 3）.Thermodynamic parameters of the extraction reaction were obtained from the thermodynamics analysis,which illustrates that higher temperatures show a negative effect on the extraction.Extraction isotherm was obtained with 2.16 mol/L TBP for a typical solution containing 0.1 mol/L of bismuth and 1.0 mol/L of hydrochloric acid.About 98.5 % of bismuth has been extracted from the leaching solution under the optimum condition.Moreover,oxalate was explored as a precipitation stripping agent for BiCl3·x TBP（x=2 or 3） complexes,by which Bi（Ⅲ） was stripped in the form of Bi2（C2O4）3·7H2O.A stripping efficiency of 99.3% was obtained in only one stage at the phase ratio of 1 and TBP also could be recycled.Therefore,the method is an efficient,effective and highly selective approach to extract Bi（Ⅲ） and to recover metal bismuth.
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