Advanced oxidative decolourisation of Reactive Yellow 14 azo dye by UV/TiO2, UV/H2O2, UV/H2O2/Fe2+ processes-a comparative study

The decolourisations of reactive azo dye, Reactive Yellow 14 (RY14), by three different advanced oxidation processes have been investigated. The dye is effectively decolourised by all these processes. The effects of dye adsorption, catalyst loading and dye concentration on the UV/TiO2 process have been studied. These parameters influence the decolourisation rate. In UV/H2O2 and UV/H2O2/Fe2+ processes, H2O2, Fe2+ dosage and dye concentration have strong influence on the decolourisation. The kinetics of heterogeneous photocatalytic decolourisation is discussed interms of Langmuir-Hinshelwood (L-H) kinetic model. The decolourisation rates observed are quite different for each system. The decolourisation efficiencies of these processes are in the following order UV/H2O2/Fe2+ > UV/TiO2 > Fe2+/H2O2 > UV/H2O2.