Photo Degradation of Reactive Dye Acid Red 1 Under UV-C Radiation Using Fly Ash from Different Thermal Power Plants

A comprehensive study was carried out on two different fly ashes used as a catalyst for the degradation of Acid Red 1 using ultraviolet rays. These fly ashes are collected from different thermal power stations located at various places in India and having different chemical compositions. One fly ashes is from lignite-based thermal power plant and the other is from the coal-based power plant. One fly ash is classified as Class C and other is not conforming to ASTM C618 classification. X-Ray Fluorescence (XRF) analysis was used to identify the chemical composition of fly ashes and SiO₂, Al₂O₃, CaO, Fe₂O₃, MgO, SO₃ and TiO₂ were found to be the major elements present it in different proportions. Various analysis were carried out on all the fly ashes like Scanning Electron Microscopy (SEM) to identify the microphysical properties, Energy Dispersive X-ray spectroscopy (EDS) to quantify the elements present in the catalyst and X-Ray Diffraction (XRD) to identify the catalyst phase analysis. The radical generated during the reaction was identified by Electron paramagnetic resonance spectroscopy (EPR). The parameters such as initial pH of the dye solution, catalyst dosage and initial dye concentration which influence the dye degradation efficiency were studied and optimised. In 60 minutes duration, the dye degradation efficiency at optimum parametric values of pH 2.5, initial dye concentration of 10 mg/L and catalyst dosage of 1.0 g/L using various fly ashes, i.e., Salam Power Plant (SPP), and Neyveli Lignite Thermal Power plant (NLTP) were found to be 40% and 95% respectively. The contribution of adsorption alone was 18% at the above mentioned optimum parametric values. Among the above four fly ashes NLTP fly ashes proved to be most efficient.