Photoelectrocatalytic Coupling of Chlorine Radicals Enhances Sulfonamide Antibiotic Degradation in Saline-Alkaline Waters in Cold-Water Fish Aquaculture

The degradation of organic matter using TiO<sub>2</sub> nanotube photocatalytic technology is limited by the short lifetime and diffusion radius of the generated hydroxyl radicals, decreasing the removal efficiency. This study developed a chlorine radical-coupled photoelectrocatalytic sy...

Full description

Saved in:
Bibliographic Details
Main Authors: Qikai Liu, Yang Liu, Yaqi Mao, Ru Li, Yujie Jiao, Jiali Lei, Fenzhen Zhang
Format: Article
Language:English
Published: MDPI AG 2025-03-01
Series:Fishes
Subjects:
Online Access:https://www.mdpi.com/2410-3888/10/3/116
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The degradation of organic matter using TiO<sub>2</sub> nanotube photocatalytic technology is limited by the short lifetime and diffusion radius of the generated hydroxyl radicals, decreasing the removal efficiency. This study developed a chlorine radical-coupled photoelectrocatalytic system, significantly enhancing the performance of TiO<sub>2</sub> nanotube arrays in removing sulfonamide antibiotics (SAs) from cold-water aquaculture systems. The highest degradation rates were observed at 5 mM NaCl and 15 mM NaNO<sub>3</sub>. When SA concentrations were 0.1–10 mg/L, degradation efficiency decreased with higher initial concentrations. The best degradation was achieved at an initial pH of 3 for SA. Humic acid and sodium acetate, natural organic matter in the water column, served as low-concentration promoters and high-concentration inhibitors. In our study, three degradation intermediates were identified, and hydrolysis and nitration reactions are proposed as the primary pathways for SA degradation. We confirmed that oxygen radicals play a major role in this system. Furthermore, toxicology experiments revealed the weakening of the toxicity of the degraded products. This study provides an efficient method for treating organic matter in cold-water fish culture water in chloride-containing saline and alkaline waters.
ISSN:2410-3888