It is important to solve the problems of biomass treatment and combined contaminants removal in environmental remediation. In this study, a calcium (Ca) modified biochar (CaBC800) was fabricated using corn stover (CS) as a raw material to remove phosphate and tetracycline (TC). The experimental results indicate that CaBC800 can adsorb both inorganic phosphate and organic TC. The entire adsorption process corresponds to pseudo-second-order kinetics and Langmuir adsorption isotherm. The maximum adsorption capacities of phosphate and TC were 33.944 and 33.534 mg/g, respectively. The phosphate adsorption was demonstrated to mainly depend on the chemical precipitation by Ca and ligand exchange by hydroxyl groups from CaBC800. Meanwhile, hydrogen bonding from oxygen functional groups and π-π interactions from aromatic rings are the main adsorption mechanisms of TC. This study provides a new adsorbent to efficiently remove phosphate and TC, and the simultaneous adsorption indicates the application potential of CaBC800 in wastewater remediation.

中文翻译：

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钙改性玉米秸秆生物炭同时吸附磷酸盐和四环素：性能与机理


解决环境修复中生物质处理和污染物联合去除问题具有重要意义。本研究以玉米秸秆（CS）为原料制备钙（Ca）改性生物炭（CaBC800），以去除磷酸盐和四环素（TC）。实验结果表明CaBC800既能吸附无机磷酸盐，又能吸附有机TC。整个吸附过程符合准二级动力学和Langmuir吸附等温线。磷酸盐和TC的最大吸附容量分别为33.944和33.534 mg/g。磷酸盐吸附被证明主要取决于 Ca 的化学沉淀和 CaBC800 中羟基的配体交换。同时，氧官能团的氢键作用和芳香环的π-π相互作用是TC的主要吸附机制。本研究提供了一种有效去除磷酸盐和TC的新型吸附剂，同时吸附表明了CaBC800在废水修复中的应用潜力。