Table_1_Effective Removal of Sulfanilic Acid From Water Using a Low-Pressure Electrochemical RuO2-TiO2@Ti/PVDF Composite Membrane.DOCX

Removal of sulfanilic acid (SA) from water is an urgent but still challenging task. Herein, we developed a low pressure electrochemical membrane filtration (EMF) system for SA decontamination using RuO2-TiO2@Ti/PVDF composite membrane to serve as not only a filter but also an anode. Results showed that efficient removal of SA was achieved in this EMF system. At a charging voltage of 1.5 V and a electrolyte concentration of 15 mM, flow-through operation with a hydraulic retention time (HRT) of 2 h led to a high SA removal efficiency (80.4%), as expected from the improved contact reaction of this compound with ROS present at the anode surface. Cyclic voltammetry (CV) analysis indicated that the direct anodic oxidation played a minor role in SA degradation. Electron spin resonance (ESR) spectra demonstrated the production of •OH in the EMF system. Compared to the cathodic polarization, anodic generated ROS was more likely responsible for SA removal. Scavenging tests suggested that adsorbed •OH on the anode (>•OH) played a dominant role in SA degradation, while O2•- was an important intermediate oxidant which mediated the production of •OH. The calculated mineralization current efficiency (MCE) of the flow-through operated system 29.3% with this value much higher than that of the flow-by mode (5.1%). As a consequence, flow-through operation contributed to efficient oxidation of SA toward CO2 and nontoxic carboxylic acids accounting for 71.2% of initial C. These results demonstrate the potential of the EMF system to be used as an effective technology for water decontamination.

从水中去除磺胺酸（SA）是一项紧迫但仍然具有挑战性的任务。本研究开发了一种低压电化学膜过滤（EMF）系统，利用RuO2-TiO2@Ti/PVDF复合膜进行SA的净化处理，该膜不仅作为过滤器，同时亦充当阳极。研究结果表明，在该EMF系统中实现了SA的高效去除。在1.5 V的充电电压和15 mM的电解质浓度下，采用2小时的液力停留时间（HRT）的流动操作，实现了高达80.4%的SA去除效率，这与该化合物与阳极表面存在的活性氧（ROS）之间增强的接触反应相符。循环伏安法（CV）分析表明，直接阳极氧化在SA降解中作用较小。电子自旋共振（ESR）光谱显示，在EMF系统中产生了羟基自由基（•OH）。与阴极极化相比，阳极产生的ROS更有可能负责SA的去除。清除实验表明，吸附在阳极上的羟基自由基（>•OH）在SA降解中起主导作用，而O2•-是一个重要的中间氧化剂，它介导了羟基自由基的产生。流动操作系统的矿物质化电流效率（MCE）计算值为29.3%，远高于流动模式（5.1%）。因此，流动操作有助于将SA高效氧化为二氧化碳和无毒羧酸，这些羧酸占初始碳含量的71.2%。这些结果证明了EMF系统作为水净化有效技术的潜力。