%0 Journal Article 
%A Riaza-Frutos, A.
%A Egea-Corbacho Lopera, Agata
%A Manzano Quiñones, Manuel Alejandro
%A Quiroga Alonso, José María
%T Oxidation of an Azo-Dye via the Photo-Fenton Process under Heterogeneous and Homogeneous Conditions
%D 2023
%@ 2073-4441
%U http://hdl.handle.net/10498/32131
%X In today’s industries, a diversity of processes give rise to increasing numbers of nonbiodegradable
compounds that need to be degraded totally or transformed to other less toxic and/or
more biodegradable compounds, before their discharge into the environment. One such compound
chosen for this study is Orange II, a representative azo-dye that is widely used and easy to monitor
in its degradation. The photo-Fenton process was used under heterogeneous and homogeneous
conditions to study several different variables. At the end of this research, a comparative study
was carried out between the two types of catalysis. It was observed that better results in primary
degradation and mineralization were provided by homogeneous catalysis. The photo-Fenton process
takes place effectively under heterogeneous and homogeneous catalysis conditions. The process is
much faster under homogeneous conditions than under heterogeneous conditions (99.9 and 24%
after 90 min, respectively, especially when only 2 ppm of iron in solution is required). Mineralization
was observed through total organic carbon, through the variable C/Co as a function of time during
photo-Fenton and Orange II degradation, and the data obtained for the final oxidation capacity are in
agreement with the experimental percentages of mineralization. A linear fit was observed using the
Chan–Chu kinetic model for heterogeneous and homogeneous catalysis. For heterogeneous catalysis,
56% mineralization was reached whereas the model predicts 63%. Regarding homogeneous catalysis,
according to the model, 100% mineralization is reached because (1/ ) takes a value greater than 1
since the model calculates it on infinite time.
%K oxidation
%K photo-Fenton
%K wastewater
%K azo-dye
%~ Universidad de Cádiz