Developments in new processes for colour removal from effluent

Dye effluent is a highly dispersible aesthetic pollutant that can contribute to aquatic toxicity. It is difficult to treat, as most dyes are highly stable molecules that resist degradation by light, chemical, biological and other treatments. Removing colour from textile effluent prior to it being discharged into sewers is currently a major challenge to environmental, as well as the textile, scientists. The authors review the various textile wastewater decolorisation techniques being applied and researched to remove colour from textile wastewater. The recent developments in the promising areas of bioadsorbents, hydrogen peroxide-based techniques and the use of microbial cultures for decolorisation are highlighted.