Kinetic modelling of TOC removal by H2O2/UV, photo-Fenton and heterogeneous photocatalysis processes to treat dye-containing wastewater|
Lopez-Lopez, C.; Martín-Pascual, J.; Martínez-Toledo, M. V.; Muñío, M. M.; Hontoria, E. & Poyatos, J. M.
Wastewater from textile manufacturing introduces
recalcitrant organic compounds, such as dyes and toxic
by-products into the environment, where advanced oxidation
processes are used to treat toxic and non-biodegradable
organic pollutants which cannot be removed by traditional
methods. H2O2/UV, photo-Fenton and heterogeneous photocatalysis
(TiO2/H2O2/UV) processes were used, and the
effect of the hydraulic retention time on total organic carbon
(TOC) removal was evaluated by fitting the analytical data
for the three processes to different kinetic models. The high
correlation between empirical and modelled data was
accomplished with a pseudo-first-order model for the three
processes (R2 = 0.9823 ± 0.017). Mineralisation, decolourisation
and disinfection of textile wastewater were investigated
with laboratory-scale experiments for each process.
Data showed that when 5 g/LH2O2 was used, heterogeneous
photocatalysis was the most effective method for the
removal of TOC (94.55 %). With respect to colour, all three
processes achieved nearly 100 % removal (99.6, 99.3 and
99.9 % at 120 min for the H2O2/UV, photo-Fenton and
TiO2/H2O2/UV processes, respectively).
H2O2/UV; Heterogeneous photocatalysis; Kinetic model; Photo-Fenton; Textile wastewater