Decolourization of Reactive Dye by Catalytic Ozonation based Advanced Oxidation Process in the Presence of Nano Gypsum

Abstract

Synthetic dye wastewater released into water bodies from industrial units such as textile manufacturing, dyeing and printing etc causes a negative environmental impact. Dye pollution poses significant environmental and health concerns. There are many methods available to treat dye wastewater such as adsorption, ion exchange, membrane process, coagulation and flocculation etc., still Advanced Oxidation Process is considered to be the best vowing to its broad applicability, complete mineralization, low sludge generation, decomposition of intermediates, non-selective reactivity etc,. In present study Catalytic Ozonation, an Advanced Oxidation Process was used to decolourise C. I. Reactive Blue - 5, a persistence dye using a nanocatalyst named nano gypsum. Nano gypsum was prepared and characterized using TEM and XRD studies. The average particle size of nano gypsum was found to be 25nm. The effect of various parameters such as catalytic dosage, contact time, ozone flow rate, solution pH and initial concentration on the removal of dye were studied. The maxiumum dye colour removal of 96.7% was achieved in presence of ozone and nano gypsum catalyst at dosage of 1.5 g/L, pH of 8, contact time of 30 min and flow rate of 3 L/min.