Abstract:Under the background of the increasing demand for germanium in high and new technology, the mechanism of silicon-germanium polymerization and precipitation, and the mechanism of ultrasound-induced dispersion and depolymerization of Si and Ge were identified based on the investigation of occurrence of germanium in dust leaching residue. For the first time, the correlation analysis provided substantial evidence for Ge and Si polymerization precipitation conjecture. The Ge-Si correlation coefficient k is 66.57, and the correlation fitting degree R2 is as high as 97.99%. In the leaching process of zinc oxide dust containing germanium, silicon ions in the solution will polymerize to form silicic acid colloids to adsorb germanium in the solution, causing germanium loss of 14.81%, resulting in low industrial recovery rate of germanium. After ultrasound is introduced into the leaching process, cavitation bubbles will be generated in the solution, resulting in cavitation. The energy released when the cavitation bubbles break will form local high temperature and high pressure, and generate shock waves and microjets, which will continuously impact the surface of polysilicon colloid, resulting in the increase of specific surface area of polysilicon colloid by 58.19%, pore size by 666.32%, and pore volume by 165.79%. The large particles of silica gel were depolymerized into small oligosilicic acid, and the adsorption of germanium by silica gel was reduced by 59.35% under ultrasonic condition. The high efficiency dispersion and depolymerization of silicon-germanium precipitation in zinc oxide dust leaching process established in this work can effectively recover germanium from zinc oxide dust.