RESUMO
In this paper, the photocatalytic decoloration of Acid Red 27 (AR27) has been investigated using ultraviolet (UV) irradiation in presence of SnO2 nanoparticles. SnO2 nanoparticles were synthesized via hydrothermal process. The SnO2 nanoparticles' average crystallite sizes derived from X-ray analyses which were synthesized for 2, 12 and 24 hrs were about 3.73, 5.31 and 7.6 nm, respectively. Brunauer-Emmett-Teller (BET) analyses showed high surface area of about 183, 120 and 90(m2/g), respectively for aforementioned synthesized samples. Our investigations indicated that reaction rate constant and photocatalytic efficiency of AR27 decoloration have a direct relation with SnO2 nanoparticles' specific surface areas and band gap energies. Decoloration kinetics was investigated by using Langmuir-Hinshelwood model. The values of the adsorption equilibrium constant, K[AR27], and the kinetic rate constant of surface reaction, kc, were found to be 0.0924 (l/mg) and 0.2535 (mg/l min), respectively.
