Interaction between chlortetracycline and calcium-rich biochar: Enhanced removal by adsorption coupled with flocculation
Interaction between chlortetracycline and calcium-rich biochar: Enhanced removal by adsorption coupled with flocculation
复制标题
金霉素与富钙生物炭之间的相互作用：通过吸附和絮凝增强去除效果
DOI：
10.1016/j.cej.2019.122705
复制
发表时间：
2020-02-15
影响因子：
15.1
通讯作者：
Dai, Lichun
中科院分区：
文献类型：
--
作者：
Xu, Qi;Zhou, Qin;Dai, Lichun
抗生素在环境中的高残留浓度对动物和人类的健康构成了威胁，因此，去除这些抗生素是一个迫切需要解决的问题。在这项研究中，富含钙的生物炭（CRB）从天然有机-无机复合材料（即，研究了蟹壳对水溶液中金霉素（CTC）的去除效果。进行批实验以探索CRB和CTC之间的相互作用，以表征CRB去除CTC的能力。结果表明，随着CTC初始浓度的增加，系统的平衡pH值降低，导致CTC去除过程复杂。具体而言，在低初始浓度的CTC，主要发生通过吸附，这是很好地描述了Freundlich等温模型。在298 K时，CRB对CTC的吸附容量达到1432.3 mg g（-1）.通过动力学模型估计吸附速率，伪二级模型显示出与不同浓度下的动力学数据的良好拟合。吸附和絮凝是去除高初始浓度CTC的主要原因。在298 K时，最大去除量为5048 mg g（-1）.微观表征和宏观分析结果表明，CTC的去除过程主要包括阳离子桥连、p-p相互作用、静电相互作用和氢键作用，并随初始浓度的变化而变化。因此，基于CRB的高效和低成本，这种材料有望成为去除抗生素（例如，并控制其在环境中的迁移。
A high residual concentration of antibiotics in the environment represents a to the animal and human health, thus, removal of these antibiotics is an urgent problem in need of a solution. In this study, calcium-rich biochar (CRB) pyrolyzed from a natural organic-inorganic-composite (i.e., crab shell) was investigated for its significant efficiency in removing efficiency of chlortetracycline (CTC) from aqueous solution. Batch experiments were conducted to explore the interaction between CRB and CTC to characterize the ability of CRB to remove CTC. Results showed that the equilibrium pH of the system decreased as the initial concentration of CTC increased, resulting in a complicated CTC removal process. Specifically, at a low initial concentration of CTC, the predominantly occurred through adsorption, which is well-described by the Freundlich isotherm model. The adsorption capacity of CRB for CTC reached 1432.3 mg g(-1) at 298 K. Adsorption rates were estimated by kinetic models, and the pseudo-second-order model displays a good fit for the kinetic data at various concentrations. Adsorption and flocculation were responsible for the removal of CTC at a high initial concentration. The maximum removal capacity was 5048 mg g(-1) at 298 K. Microcosmic characterization and macroscopic results demonstrated that cation bridging, p-p interaction, electrostatic interaction and hydrogen bonding could be involved in the removal process, which varied with the initial concentration of CTC. Therefore, based on the high-efficiency and low-cost of CRB, this material promises to be an ideal candidate to remove antibiotics (e.g., CTC) from wastewater and control their transport within the environment.