Abstract
In this study humic acids, which are known to be a heterogeneous group of organic macromolecules
found in natural waters, were oxidized using ozonation and photocatalysis in a sequential system.
Ozonation was employed for achieving partial oxidation of humic acids prior to photocatalytic oxidation.
Degradation of humic acid was explained by using pseudo first order reaction rate model based on UV-vis
measurements. An improvement was achieved in the photocatalytic degradation rates with respect to the
degree of pre-oxidation by ozonation. Due to the surface oriented nature of photocatalysis, adsorption characteristics
of partially oxidized humic acid samples on