부산대학교 도서관

The applicability of utilizing solvent extraction processes of manganese (Mn) and zinc (Zn) from chloride leachate of spent zinc–carbon (Zn–C) batteries has been studied by using di-2-ethylhexyl phosphoric acid (DEHPA) as an extractant agent. The effect of five factors (equilibrium pH, O/A ratio, temperature, extractant concentration, and diluent type) were investigated. According to the results gained, the appropriate solution pH level for DEHPA was found to be 6.5. With DEHPA (20%, v/v), 77.50% Mn and 100% Zn were extracted, within 15 min contact time at a 1:1 aqueous/organic ratio and 50 °C temperature. Also, a McCabe–Thiele diagram was drawn and one single-step extraction for Zn and a two-stage process for Mn were needed to achieve the highest extraction efficiency. ΔH as a thermodynamic parameter was calculated and found to be 18.39 kJ/mol for Mn and − 245.50 kJ/mol for Zn, respectively, indicating that the extraction process was endothermic for Mn and exothermic for Zn. A desirable stripping of Mn and Zn from the loaded organic phase could be obtained using a stripping solution of 6 M HCl.Graphical Abstract: