Physical effect of ultrasonic on leaching system of zinc oxide dust containing germanium

Abstract

Abstract Insufficient reaction between dust and sulfuric acid during leaching of zinc oxide dust containing germanium is a major reason for the low leaching efficiency of germanium. This paper makes use of the unique physical effect of ultrasonic wave to play an important role in strengthening the leaching process. Research found that with ultrasonic enhanced leaching, on the one hand, the surface tension and viscosity of the leaching solution decreased by 5.94 and 32.73 %, respectively; on the other hand, for the leached mineral, the contact angle decreases, the surface free energy increases by 9.43 %, the particle size decreases 40.92 %, and the specific surface area and pore volume respectively increase 94.10 and 54.05 %, which reduces the contact resistance between sulfuric acid and dust, making the reaction between them more completely and in-depth. Therefore, the leaching rate is accelerated and the germanium leaching efficiency is increased. Under ultrasonic condition, the leaching efficiency of germanium is enhanced by 3.94 % and the time to reach equilibrium is shortened by about 40.00 %. The above findings can provide theoretical guidance for the extended application of ultrasound in hydrometallurgy and the efficient leaching of germanium-containing zinc oxide dust.