Iron electrocoagulation activated peracetic acid for efficient degradation of sulfamethoxazole

作者：Zhan, Huan; Liu, Xiaoyan; Huang, Jinbing; Liu, Xian; Zhang, Xulong; Yao, Jiaxiong; Xie, Shiwei^*

来源：Chemical Engineering Research and Design, 2023, 200: 244-255.

DOI：10.1016/j.cherd.2023.10.042

• Electrocoagulation
• Activation
• Peracetic acid
• Sulfamethoxazole
• Buffering

Activation of peracetic acid (PAA) by Fe species is the attractive advanced oxidation processes for the removal of antibiotics. However, achieving optimal performance in many of these processes often requires acidic pH conditions, which impedes practical application. In this study, an iron electrocoagulation (EC) system was devised to for activate PAA and oxidate sulfamethoxazole (SMX). Under optimal conditions, the degradation of SMX by the EC/PAA system reached 96.2% within 15 min, with a pseudo-first order reaction constant of 0.241 min -1, but only consuming 0.044 kW & sdot;h/m3. Interestingly, the EC/PAA system showed a high buffering capacity in the initial pH range of 4-8 to maintain the final pH of around 7. The quenching experiments revealed both free radical and non-free radical pathways involved in the oxidation of SMX in the EC/PAA system. Specifically, the active species, including center dot OH, organic radicals (CH3COO center dot and CH3COOO center dot) and 1O2, contribute 86.77%, 5.53% and 7.70%, respectively. These findings suggest that the EC/PAA system has unique advantages and potential for the degradation of antibiotic organics such as SMX in aquatic environments due to its strong oxidative capacity, wide pH range and high buffering capacity.