Abstract

The kinetics of oxidation with ozone of 1,3,6-naphthalenetrisulfonic acid was analysed by studying the influence of different experimental parameters such as the concentration of tert-butyl alcohol (2-methyl-2-propanol), initial concentration of the acid, pH, and temperature. The rate constant of the direct reaction at 25°C was calculated (k D=6.72M -1S -1). The constant of the free radical reaction was determined with the competitive kinetics method, using sodium 4-chlorobenzoate as reference compound, obtaining a value of k OH=3.7×10 9M -1S -1. It was demonstrated that even at very acid pH values, 80% of the 1,3,6-naphthalenetrisulfonic acid was degraded by free radical reactions, so that the ozonation of this acid may be considered an advanced oxidation process. © 2002 Society of Chemical Industry.