Shi Qiu-Jun, Liu An-di, Tang Bo-Bin, Wei Shi-Qiang, Zhang Jin-Zhong
Chongqing Key Laboratory of Agricultural Resources and Environment, College of Resources and Environment, Southwest University, Chongqing 400715, China.
Technical Center, Chongqing Customs, Chongqing 400020, China.
Huan Jing Ke Xue. 2020 Apr 8;41(4):1725-1733. doi: 10.13227/j.hjkx.201910110.
The excessive use and abuse of antibiotics has brought about serious threats to water environmental safety and human health. It is necessary to develop efficient, cheap, and environmentally friendly treatment technologies for antibiotics. In this work, a Ni-doped Sb-SnO microporous ceramic ring particle electrode was prepared by the dipping method and characterized by scanning electron microscopy, energy dispersion spectroscopy, and X-ray diffraction. The electrocatalytic oxidation ability and kinetic characteristics of sulfadiazine (SDZ) were studied using the prepared electrode, and the degradation pathways of SDZ were analyzed preliminarily. The results showed that Ni and Sb-SnO crystals were loaded on the particle electrode surface, which is beneficial for electron transfer and SDZ adsorption and improvement of electrocatalytic oxidation efficiency. Under the conditions of 0.02 mol·L NaCl solution (pH 8), 15 mA·cm of current density, and 15 g particle electrode, 50 mg·L SDZ could be completely removed on the three-dimensional electrode within 15 min. The removal efficiency of TOC in the reaction solution reached 80.8% for 3 h degradation and was 17.6% higher than that with two-dimensional electrode. The kinetic process of the electrocatalytic oxidation could be well described by the first-order reaction kinetic model, and the rate constant was 0.329 min. The degradation products of SDZ were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the possible pathways of electrocatalytic degradation mainly include the fractures of S-N bond on sulfamido and C-N bond on pyrimidine ring, desulfonation, deamination, and·OH oxidation.
抗生素的过度使用和滥用已对水环境安全和人类健康造成严重威胁。开发高效、廉价且环境友好的抗生素处理技术很有必要。在这项工作中，采用浸渍法制备了镍掺杂的锑锡氧化物微孔陶瓷环颗粒电极，并通过扫描电子显微镜、能谱和X射线衍射对其进行了表征。利用所制备的电极研究了磺胺嘧啶（SDZ）的电催化氧化能力和动力学特性，并初步分析了SDZ的降解途径。结果表明，镍和锑锡氧化物晶体负载在颗粒电极表面，有利于电子转移、SDZ吸附及电催化氧化效率的提高。在0.02 mol·L NaCl溶液（pH 8）、15 mA·cm电流密度和15 g颗粒电极的条件下，50 mg·L的SDZ在三维电极上15分钟内可被完全去除。反应溶液中TOC的去除效率在3小时降解时达到80.8%，比二维电极高17.6%。电催化氧化的动力学过程可用一级反应动力学模型很好地描述，速率常数为0.329 min。通过液相色谱-串联质谱（LC-MS/MS）鉴定了SDZ的降解产物，电催化降解的可能途径主要包括磺胺基上S-N键和嘧啶环上C-N键的断裂、脱磺化、脱氨和·OH氧化。
