Optimum Dioxide Titanium Nanoparticles in Dioxide Titanium /Bentonite Composite for Sonophotocatalytic decolorization of Methyl Orange dye

Dye  is  considered  as  one  of  the  most  important  environmental  pollutants  in  industrial wastewater due to its harmful effects on both human and environment. This study was aimed to determine Optimum Dioxide Titanium Nanoparticles in Dioxide Titanium /Bentonite Composite for Sono-photocatalytic de-colorization of Methyl Orange dye. 

In this study, bentonite was used as the substrate to stabilize titanium dioxide photo-catalyst and the optimum amount of stabilized titanium dioxide nanoparticles in titanium dioxide/ bentonite composite which was evaluated for sono-photocatalytic removal of methyl orange dye. Accordingly, the optimal conditions for the photocatalytic process performance in dye removal included the effect of pH, methyl orange concentrations and nanocomposite doses.

Structural properties of bentonite/titanium Dioxide composites and pure titanium dioxide nanoparticles were investigated using scanning electron microscope (SEM), Diffuse Reflectance Spectroscopy (DRS) and X-ray diffraction (XRD). Finally, the possibility of reuse of photo-catalyst was investigated in three periods. Based on SEM results, reducing the amount of titanium dioxide reduced the number of nanoparticles formed on the bentonite surface. XRD and DRS analyses showed successful composite formation. The optimum amount of titanium dioxide nanoparticles in titanium dioxide/bentonite composite was obtained for sono-photocatalytic dye removal of methyl orange with the titanium dioxide powder to bentonite ratio of 1: 2.5 in the primary mixture.

  The study showed that increasing the amount of photo-catalyst in the reaction medium increased the speed and efficiency of the dye removal but its excessive increase had a negative effect on the reaction. The best conditions for dye degradation were obtained using titanium dioxide/bentonite nanocomposite at pH 4. According to the results, the increase in concentration increased dye removal time. Finally, the sono-photocatalytic composite efficiency was acceptable after three times of reuse.