Efficacy of photocatalytic removal of Chromium in the presence of organic matter from aqueous medium by useing TiO2 nanoparticles synthesized by sol gel

Widespread use of Chromium and their compounds in many industries, including plating, steel production, and wood protection and tanning leather, can result in the discharge of large amounts of pollutants to receiving waters, leading to toxic effects on human health and the environment. The aim of this study was to determine the efficiency of the photocatalytic process to remove Chromium in the presence of organic matter from the aqueous medium by using nanoparticles of TiO2 synthesized by sol gel.

This was an experimental study. After nanoparticle synthesis, we used FTIR, SEM, XRD for analysis of nanoparticles. The photocatalytic process for Chromium removal was performed using a discrete stream reactor and Uv light bulb with 30 watts intensity. Then, the effects of independent variables, including pH, concentration of nanoparticles, contact time and the presence of interfering organic matters such as phenol, EDTA, CCl4, methanol and humic acid on the efficiency of the removal of Chromium in an aqueous medium were evaluated.

The results showed efficiency of Chromium removal increased after decreasing pH. Also, increasing the concentration of nanoparticles and contact time led to increased removal efficiency. We found reduced removal efficiency after increasing concentrations of the pollutants. Removal efficiency of Chromium increased in the presence of EDTA, but methanol, phenol, humic acid, and carbon tetrachloride reduced its removal efficiency.

Photocatalytic oxidation with titanium oxide nanoparticles synthesized by sol-gel method can be an effective way for removal of Chromium from aqueous medium.