Main content area

Enhanced Mineralization of Gaseous Organic Pollutant by Photo-Oxidation Using Au-Doped TiO2/MCM-41

Tangale, Nilesh P., Belhekar, Anuja A., Kale, Kishor B., Awate, Shobhana V.
Water, air, and soil pollution 2014 v.225 no.2 pp. 1847
Fourier transform infrared spectroscopy, absorption, acetone, adsorption, air, catalysts, desorption, gold, mineralization, nitrogen, reflectance, surface area, temperature, volatile organic compounds
The synthesis, characterization, and photocatalytic evaluation of titania-loaded MCM-41 with and without Au doping are reported in the present study. The samples were characterized by powder XRD, TEM, low temperature N₂adsorption/desorption, UV–Vis, and FTIR. UV-induced vapor-phase photo-oxidation of acetone was used as a probe reaction to study the role of Au in mineralization of volatile organic compounds (VOCs), viz. acetone at different concentrations. The doping of Au in titania-loaded MCM-41 resulted in the decrease of BET surface area, total pore volume, and average pore size. UV–Vis diffuse reflectance spectra of Au-doped titania-loaded MCM-41 showed the red shift in their absorption bands compared to titania-loaded MCM-41. The activity of mineralization of acetone by photocatalysis for 2 % Au-doped titania-loaded MCM-41 was found to be ∼1.6 times higher than titania-loaded MCM-41. The presence of cocatalytic nanosized gold might be responsible for their enhanced activity on account of the delayed recombination of electron/hole pair. Although, almost complete mineralization of acetone was observed irrespective of the initial concentration of acetone in air (up to 3.72 mol%) by all the catalysts, 2 wt.% Au-doped titania-loaded MCM-41 has shown the most enhanced activity.