Physicochemical treatment of synthetic textile wastewater containing reactive black 5

Abstract

The colour removal ability of two physicochemical methods, adsorption and Fenton oxidation to decolourize synthetic textile wastewater containing reactive black 5 dye was investigated. Phosphoric acid activated saw dust and rice husk carbon were prepared by using simple methods. Both types of activated carbon showed more than 90% colour reduction at the dosage of 0.1 g of activated carbon per 100 cm3 of wastewater at a 2.5 hour stirring time. Percent colour reduction was increased with increasing the amount of both H3PO4 activated saw dust and rice husk carbon and the contact time. Percent colour reduction was increased from 30% to 90% when the adsorbent dosages were increased from 0.025 to 0.1 g. When the H2O2 dosage was changed from 0.25 to 2 mM, the percentage colour reduction was increased from 20% to 86% at pH 3 at a constant Fe2+ concentration of 0.5 mM. When the Fe2+ concentration was changed from 0.01 to 0.1 mM while keeping the H2O2 concentration at 2.0 mM, the percentage colour reduction was increased from 17% to 81%. According to the results of this study, both adsorption onto activated carbon and the Fenton oxidation may provide promising solution for the removal of Reactive Black 5 dye from textile effluents economically.