Use of TiO2 Media by Sputtering and Peroxy Gel Method for Wastewater Reuse in the Electronics Industry

This paper describes the use of UV/TiO2 technology to remove low molecular weight compounds typically persistent in the wastewater reuse process in the electronics industry. The photocatalyst was immobilized at the surface of media through sputtering and the peroxy gel method with subsequent annealing for strong photocatalytic activity and good mechanical strength. Preparation conditions of photocatalytic media were chosen by SEM and XRD analysis results, which exhibited high intensities for the anatase phase capable of efficient hydroxyl radical formation. The photocatalytic activity of prepared media was tested in synthetic wastewater composed of low molecular weight compounds. The removal efficiencies of acetaldehyde, ethanol, methanol, and isopropyl alcohol reached over 90% within 30 minutes, while those of acetone and acetonitrile did so within 60 minutes. The differences resulted from production of acetone as a byproduct from isopropyl alcohol and the stronger binding energy of acetonitrile than other compounds. After discussion of the advantages and engineering aspects, we suggest that prepared media has great potential in application for the electronics wastewater reuse process.