Separation of Gallium and Arsenic from the Wafer Grinding Extraction Solution

摘要

This work investigates the separation of gallium and arsenic from the wafer grinding extraction solution. The wafer grinding extraction solution was generated using hot and concentrated nitric acid. In this study, adsorption technology was employed to remove the toxic arsenic from the extraction solution. Ferric hydroxide was the adsorbent employed to adsorb arsenic. The effects of pH value, contact time, absorbent dosage, and chloride ion concentration on the efficiency of adsorption of gallium and arsenic were investigated. The optimal conditions for recovering gallium and removing arsenic were a raw pH of 0.2, a contact time of 6 min and a ferric hydroxide concentration of 30.4 g/L. Additionally, adding chloric ions reduces the residual percentage of gallium (Re_(Ga)) and the percentage of arsenic removed (R_(As)). Under these optimal conditions, Re_(Ga) and R_(As) are 100 and 80%, respectively.