氯离子作用下N235对铋的萃取性能

采用溶剂萃取法脱除铜电解液中的杂质，在水相料液中添加助萃剂Cl-，研究Cl-作用下萃取剂N235对铋的萃取性能.考察有机相N235体积分数、水相助萃剂Cl-浓度、有机相与水相的体积比 (相比)、萃取时间、萃取温度等因素对铋萃取率的影响.研究结果表明:有机相N235体积分数、水相助萃剂Cl-浓度和相比是影响铋萃取率的主要因素；较为适宜萃取铋的条件为:水相硫酸浓度为3.0 mol/L，氯离子浓度为0.1 mol/L，萃取剂N235体积分数为20 %，相比为1:1，萃取时间为5 min.在此实验条件下，铋的一级萃取率达到97.3 %(质量分数). 

Extraction performance of bismuth with N235 under Cl-assisted extraction

Bismuth impurity in copper electrolyte could be efficiently removed by solvent extraction. The performance of extracting bismuth with N235 was investigated by adding assisting extraction agent into aqueous phase. The effects of various factors such as volume fraction of N235, concentration of assisting reagent, volume ratio of organic to aqueous phase (V(O)/V(A)), reaction time and temperature on bismuth extraction ratio were investigated. The results show that volume fraction of N235, concentration of assisting extraction agents and phase ratio are the main factors influencing the bismuth extraction ratio. The optimal extraction condition is as follows: the sulfuric acid concentration is 3.0 mol/L; assisting extraction agent concentration is 0.1 mol/L; volume fraction of extraction N235 in the organic phase is 20 %; the phase ratio is 1:1; and extraction time is 5 min. Under the optimized condition, the one-stage extraction efficiency of bismuth is 97.3 %.