Organic Phase Modification of YW100 Extraction System: Extraction of Germanium Using YW100 + D2EHPA + N235

In this study, germanium was selectively extracted using an organic phase containing 3% C7-9 hydroxamic acid (YW100), 15% Di(2-ethylhexyl)phosphoric acid (D2EHPA), 35% Tri(octyl-decyl) amine (N235), and 47% kerosene from the Ge-slag sulfuric acid leaching solution. Then, the solution was stripped by the 1 mol/L NH4F solution to obtain a germanium extraction ratio of 99.4% and a stripping ratio of 96.2% after three extraction and stripping stages. The total organic carbon (TOC) was used to characterize the total organic matter amount in the raffinate. Compared to the "YW100 + D2EHPA" extraction system, the "YW100 + D2EHPA + N235" extraction system reduced 80% of the water solubility loss of YW100 and improved the phase separation per-formance. In addition, the mechanisms of germanium extraction and phase separation improvement were studied. The coordination number of YW100 and germanium is 3, while the coordination number of D2EHPA is 1.