Kinetic study of Reactive Black 5 degradation by Fe2+/S2O82− process via interactive model-based response surface methodology

This study aimed to kinetically discover optimal conditions on characteristics of Reactive Black 5 decolorization/degradation via ferrous (Fe 2+ )-activated potassium persulfate (PS). Monod - like kinetics and interactive model-based response surface methodology (RSM) were applied to fitting and predict optimize treatment. Biodegradability of the intermediates was also tested by shaking culture with two species ( Proteus hauseri ZMd44 and Shewanella sp. WLP72). Results showed that the optimal degradation efficiency was predicted (through RSM) as pH 3.72, (PS) = 0.39 mM, and (Fe 2+ ) = 0.29 mM. The transformation products (dl-4-hydroxymandelic acid, benzoic acid, benzene, formic acid, oxalic acid and acetic acid) were less toxic than the original dye solution. According to those results, clean-up of dye pollutants by the Fe 2+ /S 2 O 8 2− process is feasible as a pre-processing for the biodegradation, and the predicted optimal conditions are meaningful for further industry utilization.