Deposition of Activated Carbon/TiO2 on Polystyrene Polymer and Its Performance in Photodegradation of Methylene Blue

Abstract

Activated carbon (AC) combined with TiO₂ photocatalyst can be used as a hybrid material in water purification. However, the dispersed–composite of AC/TiO₂ in water needs additional treatment to obtain clean water, so it is considered less effective. This study aims to deposit AC/TiO₂ on polystyrene (PS) polymers with various concentrations of TiO₂ and study its ability as methylene blue adsorbent. The synthesis of AC from orange peel waste was carried out with a carbonization temperature of 600ºC and chemically activated with 10% (w/v) ZnCl₂ solution. AC was then composited with TiO₂ using a simple mixing method for 30 minutes with variations of TiO₂ of 10%, 15%, 20%, and 25%. The AC/TiO₂ composite was then deposited on the surface of the PS granules by thermal milling method at 250ºC for 1 hour. SEM characterization on the surface of AC/TiO₂ composite shows that the layer has a homogeneous distribution of TiO2 particles attached to the AC. The composite was then applied to degrade MB under solar irradiation. UV-Vis characterization was carried out as a quantitative parameter in measuring MB concentrations. MB degradation for 8 hours of irradiation showed that the concentration of 15% had the highest efficiency, which is 83.75%. In conclusion, a thin film of AC/TiO₂ on PS granules has high performance in photodegrading the dye in MB.

Keywords: activated carbon, TiO₂, polystyrene polymer, thermal milling