Kinetics of tartrazine photodegradation by UV/H2O2 in aqueous solution

In the present work, kinetics of tartrazine decay by UV irradiation and H2O2 photolysis, and the removal of total organic carbon (TOC) under specific experimental conditions was explored. Irradiation experiments were carried out using a photoreactor of original design with a low-pressure Hg vapour lamp. The photodegradation rate of tartrazine was optimised with respect to the H2O2 concentration and temperature for the constant dye concentration of 1.035 x 10(-5) M. Tartrazine degradation and the removal of TOC followed the pseudo-first-order kinetics. The much higher k (obs) value for tartrazine degradation (7.91 x 10(-4) s(-1)) as compared with the TOC removal (2.3 x 10(-4) s(-1)) confirmed the presence of reaction intermediates in the solution. (C) 2013 Institute of Chemistry, Slovak Academy of Sciences