Photocatalytic Removal of Toluene from Air Using Glass Foam Coated with Titanium Dioxide Nanoparticles

Toluene, is usually present in gasoline, thinner, and other petroleum products and is one of the volatile organic compounds that causes air pollution and adverse health effects. The aim of this study was to determine the kinetics of toluene removal from the air by photocatalytic method using foam glass coated with titanium dioxide nanoparticles.

In this experimental study, a glass chamber was used as a closed space. A quartz tube filled by glass foam coated with titanium dioxide nanoparticles was used as air filter. The air filter was placed inside the chamber and an air suction pump was connected to it and a UV lamp was installed next to the air filter. Toluene was injected into the chamber. The contaminated air was passed through the filter and circulated in the chamber. Air samples were taken from the chamber and concentration of toluene was analyzed by Gas Chromatograph.

Brunauer-Emmett-Teller (BET) analysis showed that the average diameter of pores in glass foam was 6 nm and the specific surface area of foam glass was 36 m2/g. The SEM images confirmed coating of titanium dioxide on the surface of glass foam. Toluene removal without UV irradiation was 46%, 40%, and 37%, for 18.5, 37, and 55.5 mg/m3, respectively in 2 hour contact time, but in the presence of UV radiation the toluene removal was 100%, 95%, and 90%, respectively in contact time of 80 min. The kinetics of toluene decomposition was pseudo first order.

Glass foam can be used as a photocatalyst stabilization base to remove BTEX from the air.  This is a suitable method in removing volatile organic compounds from the air in closed spaces.