Enhanced Degradation of Rhodamibe B in Water over fluorinated Titania-Silica Photocatalyst-Adsorbent

In recent years, the development of cities and the developement of industries have resulted in the release of a wide variety of organic pollutants such as dyes into the water resources which have posed major challenges for the mankind such as the reduction of drinking water and so on. Among the most effective methods for removing pollutants and wastewater treatment that have received much attention in recent years, is the photocatalytic degradation of pollutants using TiO2 photocatalyst which matters so much due to its high ability to remove a wide range of pollutants and being low cost and environmentally friendly. However, this process suffers from major obstacles and limitations such as inactivity under the visible light, the low adsorption capacity of organic compounds on the photocatalyst surface, and so on. In this study TiO2/SiO2 photocatalyst is used in order to remove RhB as a sample pollutant under UV-A light. In order to remove an obstacle to the photocatalytic process, which is the low adsorption capacity of organic compounds on the surface, a surface modification method called fluorination was used. FTIR and N2 adsorption- desorption were used to characterize the photocatalysts. It was found that flourination replaced the surface hydroxyl groups without altering the volume and diameter of the pores and maintaining the mesoporous structure of photocatalyst, by fluoride groups, which caused the surface to be hydrophobic. This increased the adsorption capacity of RhB by photocatalysts and consequently, it improves the RhB removal process. This was proved by photocatalytic degradation tests.