Construction of Novel Electro-Fenton Systems by Magnetically Decorating Zero-Valent Iron onto RuO2-IrO2/Ti Electrode for Highly Efficient Pharmaceutical Wastewater Treatment

Pulsed versus direct current electrochemical co-catalytic peroxymonosulfate-based system: Elevated degradation and energy efficiency with enhanced oxidation mechanisms

In this work, the pulsed electrochemical (PE) system was investigated to activate peroxymonosulfate (PMS) with the addition of Fe(III) to achieve efficient degradation of sulfamethoxazole (SMX) with reduced energy consumption, in comparison with the direct current (DC) electrochemical system. The operational conditions of PE/PMS/Fe(III) system were optimized as 4 kHz pulse frequency, 50% duty cycle, and pH 3, at which 67.6% reduction of energy consumption and enhanced degradation performance were achieved compared to the DC/PMS/Fe(III) system. Results of electron paramagnetic resonance spectroscopy analysis and quenching and chemical probe experiment revealed the presence of ^•OH, SO₄^•-, and ¹O₂ in the system, with ^•OH being the dominant role. The concentrations of these active species were averagely 15 ± 1% higher in the PE/PMS/Fe(III) system than those of the DC/PMS/Fe(III) system. Identification of SMX byproducts was achieved based on high resolution mass spectrometry analysis to predict the degradation pathways. The SMX byproducts could eventually be eliminated by the PE/PMS/Fe(III) system with extended treatment time. Overall, the PE/PMS/Fe(III) system was demonstrated with high energy and degradation performance, and is appear to be an robust strategy for practical treatment of wastewater.

Current and Future Trends in Environmental Electrochemistry for Wastewater Treatment

In recent years, the demand for high-quality water has constantly been increasing, while at the same time, the legislations regarding wastewater reuse are becoming stricter [...]