<p>Numerous commercial industries utilize the solvent extraction production line to manufacture battery-grade nickel and cobalt from mixed hydroxide precipitate (MHP) sources. The identification of an appropriate and efficient extractant is essential for the production of pure nickel and cobalt as primary products. The present research utilized extractant P204 to extract MHP leaching solution, effectively removing contaminants including Cu, Ca, Mn, and Zn from Ni, Co, and Mg. Extractant P507 was employed for the co-extraction of cobalt, while extractant Cyanex 272 was utilized for the co-extraction of magnesium to get the pure nickel sulfate solution. Nevertheless, the comprehensive production line revealed a residual of MgSO₄ scrubbing solution that contained nickel and cobalt metals. The MgSO₄ solution was subjected to extraction with HBL116 and magnesium oxide saponification to recover the significant nickel and cobalt metals. The solvent extraction study was conducted to evaluate the impact of time, temperature, initial pH of the feed solution, concentration of HBL116, saponification rate, and <i>O</i>/<i>A</i> ratio. The results indicated that a 4-stage extraction procedure utilizing 35% HBL116, with an organic-to-aqueous ratio of 2:1, and a saponification ratio of 90%, could recover nickel and cobalt metals with efficiencies of 99.00% and 99.90%, respectively. The pilot test stages modified the solvent extraction procedure for a small-scale application and the suggested procedure is sustainable, comprehensive, and substantial. This research is expected to advance understanding in material science and metallurgy, particularly in metal separation by solvent extraction.</p> Graphical Abstract <p></p>