Yang Yu, Zhang Xiaodan, Chen Qiumeng, Li Siqi, Chai Hongxiang, Huang Yuming
Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Chemistry and Chemical Engineering, Southwest University, Bebei, Chongqing 400715, China.
Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), School of Urban Construction and Environmental Engineering, Chongqing University, Shapingba, Chongqing 400045, China.
ACS Omega. 2018 Nov 21;3(11):15870-15878. doi: 10.1021/acsomega.8b02581. eCollection 2018 Nov 30.
In this work, the degradation of tetracycline (TC) in water by the integrated ultrasound (US)-Fenton process was investigated. For this, a new composite Fe/N-C- ( is the molar ratio of iron salt Fe(NO)·9HO) catalyst was synthesized through simple carbonization of the mixture of glucose and iron salt Fe(NO)·9HO in the presence of ammonium chloride as the nitrogen source. The resultant catalysts were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometer, and N adsorption-desorption, showing a typical graphite porous structure and good magnetic properties. The results indicated that the optimized Fe/N-C-2 catalyst prepared with a mole ratio of glucose/Fe(NO)·9HO/NHCl of 5:2:16.8 exhibited the highest TC removal in the Fe/N-C-2/HO/US system at a wide pH range from 3.0 to 11.0. At an initial pH of 7.0, TC removal in the Fe/N-C-2/HO/TC/US system was 1.83, 18.69, and 28.75 times of that in Fe/N-C-2/TC/HO, HO/TC/US, and TC/HO systems, showing a positive synergistic action between US and Fe/N-C-2. The effects of catalyst dosage, HO concentration, ultrasonic power, humic acid, and coexisting anions on TC removal were investigated. The preliminary analysis suggested that the Fe-N species and the graphite N dispersed in the carbon matrix are responsible for the efficient catalytic activity. By a simple magnetic separation, the Fe/N-C-2 catalyst was easily recovered and used for the next degradation experiment. Above 88% catalytic ability of Fe/N-C-2 was retained even after six successive runs, suggesting its good reusability. The simple preparation strategy, good magnetic property, and good catalytic ability of the Fe/N-C-2 materials make them promising alternative Fenton-like catalysts for the antibiotics abatement in water.
在这项工作中，研究了超声（US）-芬顿联合工艺对水中四环素（TC）的降解情况。为此，以氯化铵为氮源，通过葡萄糖与铁盐Fe(NO₃)₃·9H₂O的混合物简单碳化合成了一种新型复合Fe/N-C-（为铁盐Fe(NO₃)₃·9H₂O的摩尔比）催化剂。通过X射线衍射、扫描电子显微镜、透射电子显微镜、X射线光电子能谱、傅里叶变换红外光谱、振动样品磁强计和N₂吸附-脱附对所得催化剂进行了表征，结果表明其具有典型的石墨多孔结构和良好的磁性。结果表明，以葡萄糖/Fe(NO₃)₃·9H₂O/NH₄Cl摩尔比为5:2:16.8制备的优化Fe/N-C-2催化剂在pH值3.0至11.0的宽范围内，在Fe/N-C-2/H₂O₂/US体系中表现出最高的TC去除率。在初始pH值为7.0时，Fe/N-C-2/H₂O₂/TC/US体系中TC的去除率分别是Fe/N-C-2/TC/H₂O₂、H₂O₂/TC/US和TC/H₂O₂体系的1.83倍、18.69倍和28.75倍，表明US与Fe/N-C-2之间存在正协同作用。研究了催化剂用量、H₂O₂浓度、超声功率、腐殖酸和共存阴离子对TC去除的影响。初步分析表明，分散在碳基体中的Fe-N物种和石墨N是高效催化活性的原因。通过简单的磁分离，Fe/N-C-2催化剂易于回收并用于下一次降解实验。即使经过连续六次运行，Fe/N-C-2仍保留了88%以上的催化能力，表明其具有良好的可重复使用性。Fe/N-C-2材料简单的制备策略、良好的磁性和催化能力使其成为水中抗生素降解有前景的类芬顿催化剂替代品。
