Application of Photocatalysts and Their Effective Parameters in the Treatment of Colored Wastewaters

In recent years, due to the reduction of freshwater resources, wastewater treatment has attracted a lot of attention. The presence of metal ions, dyes and chemicals in industrial wastewaters has caused disturbances in biological activities in the water. Dyes are compounds with a complex structure, usually toxic and resistant to biological degradation, which enters the environment by industrial wastewater. A lot of research has been done to find a way to remove dyes from wastewater. Research and development in this field have created a new process called advanced oxidation processes, particularly in the form of heterogeneous photocatalysis that converts photon energy into chemical energy. The photocatalyst is a catalyst that is activated by light radiation and converts pollutants in air or water into materials such as water and carbon dioxide. This research is a summary of the applied studies on dye removal using photocatalytic nanoparticles. Additionally, the effects of the fundamental parameters such as temperature, pH, and reaction time have also been reviewed.