Fenton and photo-Fenton oxidation of a model mixture of dyes - overall kinetic analysis

The decolorisation and mineralisation of a model mixture of reactive dyes, under Fenton and photo-Fenton conditions, have been investigated. A kinetic study was performed and rate constants and half-life times determined from batch experimental data according to a pseudo-first-order degradation kinetic model. Moreover, the use of natural or artificial light, as well as the effect of temperature, was evaluated with the aim of finding the best Fenton process to promote the efficient degradation of the standard trichromatic system. The experimental results showed that the Fenton process run under solar light was the most effective. It is suggested that Fenton- and photo-Fenton-type reactions are viable techniques for the treatment of these types of dye mixtures, according to the high levels of colour, chemical oxygen demand and total organic carbon removal.