School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007, Australia.
School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007, Australia.
Bioresour Technol. 2017 Aug;238:306-312. doi: 10.1016/j.biortech.2017.04.042. Epub 2017 Apr 13.
Competitive sorption of sulfamethazine (SMT), sulfamethoxazole (SMX), sulfathiazole (STZ) and chloramphenicol (CP) toward functionalized biochar (fBC) was highly pH dependent with maximum sorption at pH ∼4.0-4.25. Equilibrium data were well represented by the Langmuir and Freundlich models in the order STZ>SMX>CP>SMT. Kinetics data were slightly better fitted by the pseudo second-order model than pseudo first-order and intra-particle-diffusion models. Maximum sorptive interactions occurred at pH 4.0-4.25 through H-bonds formations for neutral sulfonamides species and through negative charge assisted H-bond (CAHB) formation for CP, in addition to π-π electron-donor-acceptor (EDA) interactions. EDA was the main mechanism for the sorption of positive sulfonamides species and CP at pH<2.0. Sorption of negative sulfonamides species and CP at pH>7.0 was regulated by H-bond formation and proton exchange with water by forming CAHB, respectively. The results suggested fBC to be highly efficient in removing antibiotics mixture.
磺胺甲噁嗪（SMT）、磺胺甲噁唑（SMX）、磺胺噻唑（STZ）和氯霉素（CP）在功能化生物炭（fBC）上的竞争吸附高度依赖 pH 值，在 pH ∼4.0-4.25 时吸附量最大。平衡数据通过 Langmuir 和 Freundlich 模型得到很好的表示，其顺序为 STZ>SMX>CP>SMT。动力学数据通过伪二阶模型拟合稍好于伪一阶和内颗粒扩散模型。最大的吸附相互作用发生在 pH 4.0-4.25 时，通过中性磺胺类物质形成氢键，以及通过 CP 形成负电荷辅助氢键（CAHB），此外还有π-π电子供体-受体（EDA）相互作用。在 pH<2.0 时，EDA 是吸附正磺胺类物质和 CP 的主要机制。在 pH>7.0 时，负磺胺类物质和 CP 的吸附受氢键形成和质子与水的交换调节，分别通过形成 CAHB 来实现。结果表明，fBC 非常有效地去除抗生素混合物。
