Extraction and separation of gallium by solvent extraction with 5-nonyl-2-hydroxyacetophenone oxime: Fundamentals and a case study

The rapid growth of the electronics and energy industries has necessitated an increased focus on strategic elements in recent years. Gallium is one of the most sought-after elements due to its widespread use in electronic components as well as nuclear and other energy-related applications. Gallium was extracted and separated using 5-nonyl-2-hydroxyacetophenone oxime (NHAO), which was employed for the first time in this study. Traditional log DM-log [Extractant] analysis shows that the extractant has separated Ga as a complex of 2:1 (extractant: metal) ratio. Using 0.5 M NHAO in benzene with aqueous / organic ratio of 1/1, extraction of Ga (99.2%) was completed in about 7 min at room temperature. Based on the McCabe–Thiele diagrams constructed, 2 stages are sufficient for the extraction and stripping of Ga. The selectivity or separation factor (Ga /M) > 63 was obtained for all interfering metal ions examined. Additionally, 0.5 M H2SO4 selectively stripped almost 98.8% of the Ga from the loaded NHAO. The thermodynamic analysis demonstrated that Ga extraction by NHAO is an exothermic process. Finally, the best extraction parameters for separating gallium from reference (NIM-L) and black mica (BM) source materials bearing gallium were applied with good accuracy.