Optimization of gallium and germanium extraction from hydrometallurgical zinc residues.
Harbuck-DD; Morrison-JW; Davidson-CF
Paper in Light Metals 1988 Oct; :1-7
The U.S. Bureau of Mines studied the extraction of gallium and germanium from hydrometallurgical zinc processing residues. Statistically designed experiments showed that the most significant variables were h2so4 concentration for gallium extraction and pulp- solids density for germanium extraction. Leaching the residue with 2,000 lb h2so4/st residue for 4.5 H at 80 deg. C using 20 pct pulp solids extracted 95 pct of the gallium. Optimum germanium extraction of 73 pct was obtained using the same conditions but decreasing pulp solids to 5 pct. X-ray diffraction analysis and sem techniques showed that the insoluble germanium was present in the residue as a sio2-geo2 solid solution. Additional leaching of the residue with 500 lb hf/st residue for 2 h at 80 deg. C using 10 pct pulp solids extracted 93 pct of the remaining germanium. Combined germanium extraction from sulfuric and hydrofluoric acid leaching was 98 pct.
OP; Conference/Symposia Proceedings
Paper in Light Metals 1989, Ed. by Paul G Campbell. Miner. Met., & Mater. Soc., 1988, Pp 983-989