ALUMINOTHERMIC PROCESS FOR GERMANIUM RECOVERY USING FAYALITE COPPER SLAG

Because of a limited source of germanium and its high demand caused by growing technology industry, secondary sources become attractive and suited alternatives. In the present paper copper slag containing germanium was used as source and aluminothermic reduction was adopted as mode of reduction. To achieve the recovery of germanium from fayalitic slag, characterization of the as received copper slag, effect of varying basicity on Ge recovery and feasibility of Ge recovery through off-gas, effect of varying aluminium amount on Ge recovery at 1350 °C for a two and half hour's residence time were investigated. A bench scale furnace was used for smelting. The characterization techniques of the raw slag included XRF, XRD, SEM-EDX, and AAS. Products were characterized using same techniques except XRF. The obtained results were analysed using statistical tools. Results showed that the slag was amorphous, predominantly fayalitic with the presence of low amount of magnetite. The highest recoveries of germanium in the metal increased significantly with slight increase of both the basicity and aluminium. The same behaviour was observed when the aluminium amounts increased, the recoveries increased significantly.