Electrochemical and Photoelectrochemical Decoloration of Amaranth Dye Azo Using Composited Dimensional Stable Anodes

In this paper, the authors report the results of their experimental work in the decoloration of a well-known highly toxic Amaranth dye by electrochemical and photoelectrochemical methods. Throughout this investigation, the authors used two different Dimensional Stable Anode (DSA) electrodes, namely, IrO2-Ru2O-SnO2-TiO2/Ti and Ru2O-SnO2-TiO2/Ti. The experimental results show that IrO2-Ru2O-SnO2-TiO2/Ti electrode has higher performance on amaranth decoloration than Ru2O-SnO2-TiO2/Ti electrode, but with the disadvantage of higher energy consumption. For higher degradation of Amaranth dye with both DSA electrodes, the process was carried out via photoelectrochemical method. The experimental results clearly shown the decrease in absorbance of all UV-Vis peaks due to the mineralization of the azo dye. Also, photoelectrochemical process consumes less energy under the same experimental conditions than electrochemical process. The IrO2-Ru2O-SnO2-TiO2/Ti electrode reaches a higher degradation degree of Amaranth solutions than Ru2O-SnO2-TiO2/Ti electrode using a photoelectrochemical technique.