Titanium Dioxide Mediated Photocatalytic Degradation of Methylene Blue in a Fixed Film-Type Photoreactor

A novel, cost effective and reusable TiO2-coated nonwoven media was used to investigate the photocatalytic degradation of methylene blue (MB)-containing wastewater. A falling film-type photoreactor with recirculation was designed and operated inside a black box set up with provision for three 15 W UV 350 nm lamps. Photocatalytic experiments were conducted at an initial pH= 7 and 25 °C. Dye photodegradation was studied by the change in absorbance at 660 nm using a UV-Vis spectrophotometer. Time period of exposure, initial dye concentrations (5, 10, and 15 mg/L), and mixing were investigated. More than 95% decolorization was obtained within 4, 5, and 9 h for 5, 10, and 15 mg/L of dye-containing wastewater, respectively. Results were compared with experiments using TiO2-powdered catalysts.