Separation and removal of arsenic from metallurgical solutions using bis(2,4,4-trimethylpentyl)dithiophosphinic acid as extractant

摘要

The present study aims to decontaminate arsenic from metallurgical processing solutions The extraction profile of As(V)/(III) along with some associated metal ions like Se(IV), Ga(III), Sb(III), Bi(III) , Ni(II), Cu(II), Hg(II) and Pb(II) in bis(2,4,4-trimethylpentyl)dithiophsophinic acid (Cyanex 301) has been investigated. As(V) remains unextracted whereas As(III) is quantitatively extracted into 0.1 mol L~(-1) Cyanex 301 by a sol-vating mechanism. The influence of various parameters, such as equilibration time temperature nature of diluent and mineral acid, concentration of hydrogen ion, chloride ion, metal ion and extractant on the distribution of As(III), was examined. The extracted species has been identified and loading caoacitv deter mined. The extractant has good hydrolytic stability and regeneration power, confirming its commercial viability. Conditions for the binary separation of arsenic from metal ions like Se(IV), Ga(III), Sb(III), Bi(III), Ni(II), Cu(II), Hg(II) and Pb(II) have been optimized. The proposed separation conditions were successfullv applied to galena, copper pyrite and to a synthetic copper electrolyte bath solution This resulted in the quantitative recovery of impurity-free Pb and Cu solutions. The developed procedure can be emDloved for the removal of impurities from metallurgical effluents before discharge.