Decolorization of Remazol Brilliant Blue Dye Effluent by Advanced Photo Oxidation Process (H2O2/UV system)

M S Brooks,A E Ghaly,A S Mahmoud

doi:10.3844/ajassp.2007.1054.1062

Abstract

Advanced photo oxidation processes hold great promise for the improved treatment of textile dye effluent. In this study, the effectiveness of a H2O2/UV system for the decolorization of remazol brilliant blue effluent was investigated by examining the optimum conditions for dye removal in two reactors (coil and conventional). The results showed that the coil reactor had a higher temperature profile than the conventional reactor. When the dye was fed into the reactors at 25EC, UV radiation alone was not effective as the decolorization efficiency of the conventional reactor varied from 0.0 to 12.3%, while that of the coil reactor varied from 0.0 to 7.3%, depending on the residence time used. The effect of UV radiation at 100EC was also negligible as the maximum decolorization efficiencies were 4.0 and 3.7% for the conventional and the coil reactors, respectively. Increasing the concentration of H2O2 increased decolorization efficiencies of both UV reactors. Dye decolorization also increased with residence time. More than 93% color removal of remazol brilliant blue dye was achieved with a residence time of 56 min and 100% decolorization achieved in 65 min using a H2O2 concentration of 12.50 mL LE1.

Highlights

Color in textile effluents has become identified with the dyeing of cotton products and the use of reactive dyes
The objectives of the study were to investigate the effectiveness of an advanced oxidation process (H2O2/ultraviolet light (UV)) for decolorization of remazol brilliant blue effluent and to determine the optimum conditions for dye removal
When the dye was fed at 25 ̊C, the decolorization efficiency of the conventional reactor varied from 0.0 to 12.3%, while that of the coil reactor varied from 0.0 to 7.3%, depending on the residence time used

Summary

Introduction

Color in textile effluents has become identified with the dyeing of cotton products and the use of reactive dyes. The high consumption of reactive dyes, mainly in the cotton industry, causes environmental and aesthetic problems, due to their low degree of exhaustion. A significant percentage (10-40%) of the dye remains in its hydrolyzed and unfixed form in the exhausted dye bath or is removed in the washing liquors[2]. Over 700,000 tons of approximately 10,000 types of dyes and pigments are produced annually worldwide, of which about 20% are in industrial effluents from the textile dyeing and finishing processes[1]. Many of these synthetic dyestuffs cannot be treated successfully by conventional methods due to their complex polyaromatic structure and cause health problems[3]. There is concern that the aromatic amines, which are formed as metabolites by reductive fission of the azo bond under anaerobic conditions, could pose a more serious toxic hazard than the intact dye molecules[4]

Objectives

Methods

Results