Utilization of Solar Energy for Wastewater Treatment

Abstract

The demand for clean water is increasing with the growth in world population, and obtaining an adequate supply of clean water has likely been the challenge for many countries. To solve this problem, recycling water from various sources is the best strategy. To remove the pollutants from wastewater several treatments like adsorption, photocatalysis, photo-fenton, UV radiation, thermal treatments, biological treatments, Advanced Oxidation Processes (AOP) etc. are used. AOP has gain attraction for treatment of dye wastewater. AOPs are known to produce very powerful, non-selective hydroxyl radicals that are utilized in water treatment. The hydroxyl radical (OH•) acts very rapidly with most organic compounds. Photocatalysis has received increasing attention during past decades, due to its higher effectiveness in the degradation of organic pollutants. Organics can be oxidized by photocatalyst in solar photocatalytic reactor. In recent years, there has been an enormous amount of research and development in the area of heterogeneous photocatalytic water purification process due to its effectiveness in degrading and mineralising the recalcitrant organic compounds as well as the possibility of utilising the solar UV and visible spectrum. In the present work, the effects of various operating parameters on the photocatalytic degradation of dye is presented. It was found that different parameters, such as type of photocatalyst and composition, light intensity, initial substrate concentration, amount of catalyst, pH of the reaction medium can play an important role on the photocatalytic degradation of dye wastewater.