Supported TiO 2 on Kaolin, Cordierite, and Calcite for Photocatalytic Removal of Dyes from Wastewater

Kaolin, cordierite, and calcite are investigated as supports for TiO 2 . The prepared TiO 2 /support samples are examined for the removal of organic dyes from wastewater. The samples are preliminarily investigated to identify the optimal loaded system using synthetic wastewater containing methylene blue (MB). Data indicate that the investigated support significantly affects the photocatalytic activity of the supported TiO 2 . Low photocatalytic activity toward MB degradation is observed upon using TiO 2 /calcite when compared to the unsupported TiO 2 . Interaction between calcite and titania species probably occurrs to produce the less photoactive CaTiO 3 amorphous species. Anatase TiO 2 is obtained upon using kaolin and cordierite as supports. The low photocatalytic performance of the TiO 2 /kaolin sample is also observed. A high concentration of MB on TiO 2 /kaolin surfaces blocks the photoactive sites. TiO 2 /cordierite shows the highest photocatalytic activity compared to the unsupported TiO 2 as well as the other TiO 2 /support samples. Rigid cordierite particles suppress the agglomeration of TiO 2 particles during the preparation, leading to a high exposed surface of TiO 2 towards light illumination. TiO 2 /cordierite is investigated for the removal of organic dye from real wastewater collected from a textile dyeing factory. Color removal of up to 46% is achieved upon UV irradiation.