Kong Xiangrui, Liu Yaoxuan, Pi Jiachang, Li Wenhong, Liao QianJiahua, Shang Jingge
Department of Environmental Science, China Pharmaceutical University, Nanjing, 210009, China.
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
Environ Sci Pollut Res Int. 2017 Mar;24(7):6679-6687. doi: 10.1007/s11356-017-8376-z. Epub 2017 Jan 13.
Magnetic biochar (M-BC) was derived from herbal medicine waste, Astragalus membranaceus residue, and was used as an adsorbent for ciprofloxacin removal from aqueous solutions. The M-BC was characterized by Brunauer-Emmett-Teller surface area analyses, Fourier transform infrared spectrometry, X-ray diffraction analysis, hysteresis loops, scanning electron microscopy energy-dispersive spectrometry, and X-ray photoelectron spectroscopy. The BET surface area increased from 4.40 to 203.70 m/g after pyrolysis/magnetic modification. Batch experiments were performed at different dosages, initial concentrations, contact times, and solution pHs. Adsorption performances were evaluated using Langmuir and Freundlich isotherm models, and the results indicated that the Langmuir model appropriately described the adsorption process. The kinetic data were better fitted by a pseudo-second-order kinetic model. The maximum ciprofloxacin removal was observed at pH 6 (adsorption capacity of 68.9 ± 3.23 mg/g). Studies demonstrated that magnetically modified biochar might be an attractive, cost-effective, and easily separated adsorbent for contaminated water. Graphical abstract.
磁性生物炭（M-BC）由中药材废弃物黄芪残渣制备而成，并用作从水溶液中去除环丙沙星的吸附剂。采用布鲁诺尔-埃米特-泰勒比表面积分析、傅里叶变换红外光谱、X射线衍射分析、滞后回线、扫描电子显微镜-能谱分析以及X射线光电子能谱对M-BC进行了表征。热解/磁性改性后，BET比表面积从4.40增加到203.70 m²/g。在不同剂量、初始浓度、接触时间和溶液pH值条件下进行了批量实验。使用朗缪尔和弗伦德里希等温线模型评估吸附性能，结果表明朗缪尔模型能恰当描述吸附过程。动力学数据用伪二级动力学模型拟合效果更好。在pH 6时观察到环丙沙星的最大去除率（吸附容量为68.9±3.23 mg/g）。研究表明，磁性改性生物炭可能是一种用于处理受污染水的有吸引力、经济高效且易于分离的吸附剂。图形摘要。
