Kinetic and Thermodynamic Study of the Photocatalytic Decolourization of Light Green SF Yellowish (Acid Green 5) Dye using Commercial Bulk Titania and Commercial Nanotitania

In this work, Light Green SF Yellowish (LGSF) dye was removed from aqueous solution at normal pH equal to 7.3 in the presence of bulk and nano TiO2 under UV-A light. The decolourization process of this dye at optimum conditions obeyed pseudo-first order kinetics. Based on the kinetic study, the activation energies for decolorization of dye employing the commercial bulk TiO2 and commercial nano TiO2 were found to be 48.676 kJ mol1 and 37.032 kJ mol1 respectively. Further, thermodynamic studies showed that the photocatalytic decolourization of this dye is an endothermic and non-spontaneous reaction.