Abstract: “In this study, immobilization of TiO2 powder to EPP ball with controlled-temperature melting method was developed. The photo activity of buoyant photocatalysts was evaluated using methylene blue solution under visible light irradiation(>420 nm). Based on the associated EDS analysis, the components of uncoated EPP balls are carbon and oxygen whereas those of TiO2-coated EPP balls are carbon, oxygen, and titanium, indicating that patches of TiO2 coating cover some part of EPP balls. Based on comparison of degradation efficiency between uncoated and TiO2-coated EPP balls under UV illumination, the degradation efficiency can be significantly improved using TiO2-coated EPP balls, and surface reactions in heterogeneous photocatalysis were more dominant than photoinduced radical reactions in aqueous solutions. Thus, TiO2-coated EPP balls were found to be an effective photocatalyst for photodegradation of MB in aqueous solutions. Therefore, buoyant TiO2-coated EPP balls can be used to treat co”

Keywords: Expanded polypropylene(EPP), TiO2 , Buoyant photocatalyst bal