Photocatalytic reaction and degradation of methylene blueon TiO2 nanosized particles

Abstract

AbstractPhotocatalyst has been of considerable interest due to its new technology for environmental pollution. Among the photocatalyst semiconductors, titanium dioxide is known as a photo-catalyst for the removal of environmental contaminants. In this research, we first designed anew self-made laboratory photocatalytic reactor and then photocatalytic properties of TiO2nanoparticles are studied by using UV-A light and photodegradation of methylene blue as a water pollutant evaluated until the photocatalytic process optimizes with the process parameters. The parameters that were examined include: initial dye concentration, the mass of TiO2nanoparticle, pH value, and TiO2nano-sized particles. Absorbance spectra were measured using a spectrophotometer and the concentration of the test solution was calculated by using the Beer-Lambert Law. Our test results showed that the photocatalytic UV-A/TiO2nanoparticle is a promising method for treating wastewater. The most important part is that with reduction of TiO2particles from nano to micro scale, photodegradation time becomes very slowly and even did not reach to zero after 5 h. Also, photocatalyst reaction efficiency for 10 nm TiO2nanoparticles improves to 90% within one hour and photodegradation completed after two hours, it means that the photocatalyst activity increases with increasing surface area.