Reduced the toxicity of acid black (nigrosine) dye by removal and photocatalytic activity of Tio2and studying the effect of pH, temperatue, and the oxidant agents

Abstract

This research estimated the impact of photocatalytic decolorization on 5 ppm from Acid Black 2 (nigrosine) dye by employing bulk TiO2/artificial UV-A-light system. The dye was best decolorized at pH equal to 7.4 in Edecolor. % 98.573% at 60 min and 40 °C. The effect of temperature on this photo reaction of acid black 2 dye with TiO2 indicated to the reaction is endothermic, non-spontaneous, less random and quick response. The activation energy was found to be 24.433 kJ mol-1. This photoreaction is obeyed to pseudo first order kinetic. But in the dark reaction, the adsorption reaction is exothermic and physical adsorption type. The oxidation agent such as H2O2, Fe (III) and K2S2O8 was implemented in certain quantities and produced the raised in the resistance of the adsorption process of this dye by reducing the Eremoval % from 96.666 % to 50 % at 30 min. While the addition of K2S2O8 in photoreaction is enhanced the decolorization process of this dye and increased from 68.965 % to 95.714% at 60 min.