On-line Spectrophotometric Method for Decolourizing Reaction Kinetics of Reactive Black 5 by Fenton Oxidation

Abstract

Fenton oxidation was employed to treat and decolourize the modeling wastewater of reactive black 5 by online spectrophotometry. The effects of initial FeSO₄ dosage, initial H₂O₂ dosage, pH value, initial reactive black 5 and temperature on the colour removal and decolourizing reaction rate constant were investigated. The results show that Fenton oxidation follows pseudo first order kinetics in the first stage and reaction activation energy is 3.451 kJ mol^-1. The optimum initial H₂O₂ and pH was 2.118 mM and 3, respectively. Initial FeSO₄ dosage against k_ap presents a linear correlation: k_ap = 0.1354 [Fe²⁺]_o. Intrinsic reaction rate constant of reactive black 5 and ˇOH is 7.528 × 10¹¹ M^-1 s^-1.