Photocatalytic removal of benzene from polluted waters

Benzene is one of the most dangerous and common pollutants that may be found in industrial wastes. The removal of benzene from polluted water will not only lead to the safe discharge of water into stream, but will also lead to its reuse. In this investigation, benzene was successfully removed from water by means of photocatalytic oxidation and benzene was converted to CO2 and H2O. Ultraviolet (UV)- irradiated TiO2–SiO2 aerogels were used. The catalysts were prepared by the sol-gel and supercritical drying techniques. The prepared catalysts had different SiO2 content i.e. different molar ratios (≈ 100% TiO2, anatase – TiO2:SiO2 1:1.3, arogel I – TiO2:SiO2, 1:2.6 arogel II and TiO2:SiO2, 1:3.9, arogel III). The experimental results showed that almost 100% removal of benzene from the polluted was achieved after 60 min. illumination. The experimental results had also endicated that arogel III with molar ratio of TiO2:SiO2 1:3.9 i.e. 75% w/o SiO2 is the best catalyst to be used for the photocatalytic removal of benzene.