Highly Efficient Reduction of Vanadium (V) with Histidine

Abstract

In this paper, histidine was applied to treat vanadium-containing wastewater. Several independent experimental parameters, including H2SO4 concentration, dosage of histidine, reaction time and reaction temperature, were investigated and optimized through response surface methodology. The influence on the reduction process decreased in the following order: dosage of histidine > reaction temperature > reaction time. The reduction efficiency could be achieved at 95.77% under the following reaction conditions: H2SO4 concentration of 0.2 mol/L, reaction temperature of 90 °C, dosage of histidine at n(His)/n(V) = 3.6, reaction time of 60 min and stirring rate at 500 rpm. The reduction kinetics was followed successfully with the pseudo-first-order kinetics model and the Ea for reduction of vanadium was calculated to be 25.31 kJ/mol. The reduction kinetics was affected by these factors and the kinetics model could be described by an Equation. This paper provides a versatile strategy for treatment of wastewater containing V(V) and shows a bright tomorrow for wastewater treatment.