Photocatalytic and microbial degradation of Amaranth dye (Chapter 20)

Abstract

A large number of organic azo dyes such as Amaranth, Acid Orange 7, Sunset Yellow FCF, Azorubine, etc. are produced on industrial scale. and their untreated waste is released into the aquatic system by industries such as textile, food, leather, rubber etc. These dyes are toxic and resistant to photo/biodegradation, leading to their accumulation in biological systems. This chapter presents an overview of the toxicity studies conducted on the Amaranth dye. The different photochemical and biological methods available for treatment of wastewaters contaminated with Amaranth dye are presented. This chapter also provides brief details of characterization of the nanophotocatalyst such as TiO sub(2) supported on mesoporous Al sub(2) O sub(3) and its enhanced photocatalytic degradation efficiency for Amaranth dye using visible light. The details of experimental protocols and advanced analytical techniques, such as time-resolved UV-VIS spectroscopy and LC-ESI-HRMS spectrometry, for monitoring the dye degradation kinetics, identification of degradation intermediates and products, are presented in detail, to serve as a practical guide for laboratory scale experiments. The intimate coupling of photocatalysis with microbial biodegradation methods to achieve synergistic enhancement of wastewater treatment efficiency is highlighted.