Fu Hao, Li Xuebing, Wang Jun, Lin Pengfei, Chen Chao, Zhang Xiaojian, Suffet I H Mel
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; School of Chemical Engineering, China University of Petroleum, Qingdao 266580, China.
J Environ Sci (China). 2017 Jun;56:145-152. doi: 10.1016/j.jes.2016.09.010. Epub 2016 Oct 26.
The extensive use of antibiotics has led to their presence in the aquatic environment, and introduces potential impacts on human and ecological health. The capability of powdered activated carbon (PAC) to remove six frequently used quinolone (QN) antibiotics during water treatment was evaluated to improve drinking water safety. The kinetics of QN adsorption by PAC was best described by a pseudo second-order equation, and the adsorption capacity was well described by the Freundlich isotherm equation. Isotherms measured at different pH showed that hydrophobic interaction, electrostatic interaction, and π-π dispersion force were the main mechanisms for adsorption of QNs by PAC. A pH-dependent isotherm model based on the Freundlich equation was developed to predict the adsorption capacity of QNs by PAC at different pH values. This model had excellent prediction capabilities under different laboratory scenarios. Small relative standard derivations (RSDs), i.e., 0.59%-0.92% for ciprofloxacin and 0.09%-3.89% for enrofloxacin, were observed for equilibrium concentrations above the 0.3mg/L level. The RSDs increased to 11.9% for ciprofloxacin and 32.1% for enrofloxacin at μg/L equilibrium levels, which is still acceptable. This model could be applied to predict the adsorption of other chemicals having different ionized forms.
抗生素的广泛使用导致其存在于水生环境中，并对人类和生态健康产生潜在影响。为提高饮用水安全性，评估了粉末活性炭（PAC）在水处理过程中去除六种常用喹诺酮（QN）抗生素的能力。PAC对QN的吸附动力学最好用伪二级方程描述，吸附容量用Freundlich等温线方程很好地描述。在不同pH值下测量的等温线表明，疏水相互作用、静电相互作用和π-π色散力是PAC吸附QN的主要机制。基于Freundlich方程建立了pH依赖等温线模型，以预测PAC在不同pH值下对QN的吸附容量。该模型在不同实验室场景下具有出色的预测能力。对于高于0.3mg/L水平的平衡浓度，观察到较小的相对标准偏差（RSD），即环丙沙星为0.59%-0.92%，恩诺沙星为0.09%-3.89%。在μg/L平衡水平下，环丙沙星的RSD增加到11.9%，恩诺沙星的RSD增加到32.1%，这仍然是可以接受的。该模型可用于预测其他具有不同离子化形式的化学物质的吸附。
