کاربردهای شیمی تجزیه
Mohammad Bagi; Masoumeh Tabatabaee; Ali Sheibani
Abstract
Fluoride impurities in industrial zinc sulfate electrolytes adversely affect the zinc electrowinning process by promoting zinc deposition on the aluminum cathode, thereby reducing process efficiency and product quality. In the present study, zirconium oxide (ZrO2) has been used as an adsorbent to remove ...
Read More
Fluoride impurities in industrial zinc sulfate electrolytes adversely affect the zinc electrowinning process by promoting zinc deposition on the aluminum cathode, thereby reducing process efficiency and product quality. In the present study, zirconium oxide (ZrO2) has been used as an adsorbent to remove fluoride of zinc sulfate solution during the industrial electrolysis process of zinc production. The effects of five operational parameters, including ZrO2 dosage, temperature, contact time, stirring speed and pH were systematically evaluated to optimize the fluoride removal process. The initial concentrations of zinc sulfate and fluoride in the electrolyte were 210 g/L and 453 mg/L (ppm), respectively. Under the optimum operating conditions (ZrO2 dosage of 2.0 g/L, temperature of 90 °C, contact time of 20 min, stirring speed of 200 rpm, and also pH 7), more than 90% of the fluoride was removed from the zinc sulfate electrolyte. Moreover, under industrial operating conditions demonstrated that the fluoride concentration could be reduced to below 55 mg/L (adsorption capacity=200 mg/g), significantly alleviating operational problems associated with zinc electrowinning. These findings demonstrate that ZrO2 nanopowder is an efficient and practical adsorbent for fluoride removal from industrial zinc sulfate electrolytes and has considerable potential for industrial application.
