Degradation of nonylphenol ethoxylate-9 (NPE-9) by photochemical advanced oxidation technologies

L. DE LA FUENTE; T. ACOSTA; P. BABAY; G. CURUTCHET; R. CANDAL

INDUSTRIAL & ENGINEERING CHEMICAL RESEARCH

AMER CHEMICAL SOC

Año: 2010 vol. 49 p. 6909 - 6915

0888-5885

The applicability of different photochemical advanced oxidation technologies (PAOTs), namely, direct UV-Cphotolysis, UV-C/H2O2 and UV-A/TiO2 heterogeneous photocatalysis (HP), and photo-Fenton reactions (UV-A/H2O2/Fe2+, PF), for the degradation of 300 mg L-1 nonylphenol ethoxylate-9 (NPE-9) in water is described.Different kinetic regimes for each PAOT were found, and as a result, comparative efficiencies could be obtainedonly from final parameters such as NPE-9 conversion, TOC decrease, and aldehyde production after 3 h oftreatment. The initial photonic efficiencies indicate, however, that UV-A processes make better use of photonsthan UV-C processes. Preliminary optimization of PF systems showed that the most efficient NPE-9/H2O2/Fe2+ molar ratio was 1:1:0.5. Degradation products were partially investigated. Fortunately, toxic 4-nonylphenolwas never found as a byproduct of the degradation after any of the treatments. Aldehydes were formed in allof the processes, but they appeared at a low extent in PF reactions. Therefore, PF treatments were consideredto be the best degradation processes.