Qin Tingting, Wang Zhaowei, Xie Xiaoyun, Xie Chaoran, Zhu Junmin, Li Yan
Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China E-mail:
Water Sci Technol. 2017 Dec;76(11-12):3307-3318. doi: 10.2166/wst.2017.494.
The biochar was prepared by pyrolyzing the roots of cauliflowers, at a temperature of 500 °C under oxygen-limited conditions. The structure and characteristics of the biochar were examined using scanning electron microscopy, an energy dispersive spectrometer, a zeta potential analyzer, and Fourier transform infrared spectroscopy. The effects of the temperature, the initial pH, antibiotic concentration, and contact time on the adsorption of norfloxacin (NOR) and chlortetracycline (CTC) onto the biochar were investigated. The adsorption kinetics of NOR and CTC onto the biochar followed the pseudo-second-order kinetic and intra-particle diffusion models. The adsorption isotherm experimental data were well fitted to the Langmuir and Freundlich isotherm models. The maximum adsorption capacities of NOR and CTC were 31.15 and 81.30 mg/g, respectively. There was little difference between the effects of initial solution pH (4.0-10.0) on the adsorption of NOR or CTC onto the biochar because of the buffering effect. The biochar could remove NOR and CTC efficiently in aqueous solutions because of its large specific surface area, abundant surface functional groups, and particular porous structure. Therefore, it could be used as an excellent adsorbent material because of its low cost and high efficiency and the extensive availability of the raw materials.
生物炭是通过在500℃的温度和限氧条件下热解菜花根制备而成。使用扫描电子显微镜、能量色散谱仪、zeta电位分析仪和傅里叶变换红外光谱对生物炭的结构和特性进行了研究。考察了温度、初始pH值、抗生素浓度和接触时间对诺氟沙星（NOR）和金霉素（CTC）在生物炭上吸附的影响。NOR和CTC在生物炭上的吸附动力学遵循准二级动力学和颗粒内扩散模型。吸附等温线实验数据与Langmuir和Freundlich等温线模型拟合良好。NOR和CTC的最大吸附容量分别为31.15和81.30mg/g。由于缓冲作用，初始溶液pH值（4.0 - 10.0）对NOR或CTC在生物炭上吸附的影响差异不大。生物炭因其大比表面积、丰富的表面官能团和特殊的多孔结构，能够有效地去除水溶液中的NOR和CTC。因此，由于其成本低、效率高以及原材料广泛可得，它可以用作优良的吸附材料。
