Study on ultrasonic depolymerization of Si-Ge precipitation in zinc oxide dust leaching process

Abstract

Under the background of the increasing demand for germanium in high-tech, this paper finds out the mechanism of silicon germanium polymerization precipitation by simulating the leaching process of zinc oxide dust containing germanium. By comparing and analyzing the simulation experiments under ultrasonic and conventional conditions, the mechanism of efficient dispersion and depolymerization of germanium silicon precipitation induced by ultrasonic was found out. The results show that in the leaching process of germanium-containing zinc oxide dust, due to the increase of local pH, some silicon ions in the solution will hydrolyze and polymerize to form silicic acid colloid to adsorb germanium in the solution, causing the loss of germanium 14.81%, resulting in low recovery rate of germanium industry. Ultrasonic wave was introduced in the leaching process, and the shock wave and micro-jet released by ultrasonic cavitation continuously impacted the surface of polysilicate colloid. The germanium adsorbed on the surface of the silicic acid colloid is desorbed, and the large particles of silica gel are depolymerized into small particles of silicic acid, which reduces the adsorption of silica gel on germanium. The loss of germanium under ultrasonic conditions can be reduced by 59.35%. This study can effectively realize the efficient recovery of germanium in zinc oxide dust, and provide process and theoretical basis for the sustainable development of germanium industry.