Photocatalytic decolorization of methylene blue using immobilized ZnO nanoparticles prepared by solution combustion method

Abstract

Photocatalytic decolorization of methylene blue (MB) in aqueous solution was investigated using ZnO nanoparticles immobilized on glass plate. The ZnO nanoparticles were prepared by solution combustion method (SCM) using zinc nitrate as oxidant and glycine as fuel. In the slurry ZnO system the separation and recycling of the photocatalyst is practically difficult. Thus, the ZnO nanoparticles were immobilized on glass supports to solve this problem. The effects of process parameters like, catalyst loading, initial dye concentration, and UV-radiation intensity have been investigated. The best results of MB removal were reported in the 1800 μW cm−2 UVC using two layers immobilized ZnO nanoparticles. In addition to removing the color from the wastewater, the photocatalytic reaction simultaneously reduced 62% COD. These results suggest that the photocatalytic decolorization of MB using immobilized ZnO nanoparticles prepared by SCM can be proposed and developed as a method for the treatment of colored wastewaters.

Keywords:

• ZnO nanoparticles
• Methylene blue
• Photocatalysis
• Solution combustion method