Removal Behavior of Benzohydroxamic Acid from Beneficiation Wastewater via Fe(III) Chelation and Precipitation Flotation Process

Benzoximic acid (BHA) is a commonly used collector in mineral processing industry. The accumulation of BHA in water will cause serious damage to environment. Therefore, how to efficiently treat the residual BHA in mineral processing wastewater is an important issue in the mineral processing industry. In this study, Fe(III) was used as chelating agent to separate BHA from wastewater by precipitation flotation. The optimum flotation conditions of BHA and Fe(III) were obtained by optimizing the chelation and flotation processes. The results showed that the chelating efficiency was the highest when the chelating pH was 7 and Fe(III) was 40 mg/L. When the addition amount of surfactant CTAB is 4 mg/L and the gas flow rate is 40 mL/min, the flotation removal rate of BHA reaches 90%, and the COD removal rate of the solution is 73%. The treated solution meets the first-class standard of industrial waste water discharge.