Abstract:
Release of nonionic surfactants like nonylphenol polyethoxylates in the environment generates metabolites that cause a number of estrogenic responses on aquatic organisms and thus they have been classified as endocrine disruptors. This paper deals with the electrochemical oxidation of nonylphenol ethoxylate with 9 ethoxy units (NP9EO) at Ti/RuO2/SnO2-Sb2O5-RuO2 electrodes. The doped SnO2 electrocatalytic film and the intermediate layer of RuO2, respectively, were obtained by thermal decomposition of appropriate chlorides at 550 °C and 450 °C, respectively. The electrocatalytic film was characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The electrodes were used for the removal of pollutant by electrochemical oxidation. The electrolysis were carried out by using 0.1 g/L NP9EO in 0.1 M Na2SO4 as supporting electrolyte, applied current densities of 25, 50, 75 and 100 A/m2, electrolysis time of 15, 30, 60, 120 minutes. The residual concentration of the pollutant was assessed by direct spectrophotometric determination in solution. For an applied current density of 100 A/m2 and 120 minutes of electrolysis the residual concentration of NP9EO was 33.34 mg/L.
Keywords:
electrochemical oxidation, modified SnO2 electrodes, nonylphenol ethoxylates
PDF Version