Degradation of Remazol Black B dye and its simulated dyebath wastewater byadvanced oxidation processes in heterogeneous and homogeneous media

This study focused on the degradation of hydrolysed Remazol Black B (Cl Rea ctive Black 5), a common diazo reactive dye. in aqueous solution. In the pr esence of various dye auxiliary chemicals a typical Remazol Black exhausted dyebath liquor was simulated, which was then treated with homogeneous [ozo nation with hydroxide ions, and Fe(II) or Fe(III) with hydrogen peroxide] a nd heterogeneous (titanium dioxide with UV-A irradiation) advanced oxidatio n processes. Treatment performance of the investigated advanced oxidation s ystems was comparatively assessed in terms of the environmental sum paramet ers total organic carbon, biochemical oxygen demand and spectrophotometric measurements. The results obtained clearly reveal that the investigated adv anced oxidation processes are capable of completely decolourising and parti ally mineralising the dye solution and its simulated dyebath effluent under predetermined reaction conditions. During the application of alkaline ozon ation at an ozone dose of 2340 mg/l, a three-fold biodegradability enhancem ent was observed.