Green Carbon Catalysis Center, Korea Research Institute of Chemical Technology (KRICT), 141 Gajeong-Ro, Yuseong, Daejeon 34114, Republic of Korea.
School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Bukgu, Daegu 41566, Republic of Korea.
Sci Total Environ. 2021 Jul 15;778:146327. doi: 10.1016/j.scitotenv.2021.146327. Epub 2021 Mar 9.
Radionuclide Sr in aqueous solution was removed using a large amount of banana peel (BP). Magnetized BP, mag@BP, was synthesized for recovery after the adsorption process. The synthesis was a very simple process of precipitation of BP with a magnetic substance. The synthesized adsorbent was thoroughly examined by performing Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis, and vibration sample magnetometer analysis. Moreover, mag@BP has a Sr maximum adsorption capacity of 23.827 mg/g according to isothermal adsorption, which is the best fit for the Langmuir isotherm model. In the pH effect experiment, the highest Sr adsorption capacity was found at pH 9, and it has a spontaneous adsorption mechanism through experiments on temperature, time, and selectivity, and it reaches adsorption equilibrium within a short time and has high selectivity through competitive adsorption with Na. In addition, an adsorption mechanism accompanied by ion exchange with K on the surface of BP, bonding with various functional groups, and electrical attraction were established. Therefore, mag@BP is suitable for use an environmentally friendly, low cost, and recoverable adsorbent for magnetic removal of Sr from aqueous solutions. Further, unlike other carbon-based adsorbents, it does not cause cytotoxicity.
采用大量香蕉皮（BP）去除水溶液中的放射性核素 Sr。吸附后，通过沉淀法合成了磁性 BP（mag@BP），以便回收利用。合成过程非常简单，只需将 BP 与磁性物质沉淀即可。通过傅里叶变换红外光谱、扫描电子显微镜、X 射线衍射分析和振动样品磁强计分析对合成的吸附剂进行了全面的检查。此外，根据等温吸附实验，mag@BP 的 Sr 最大吸附容量为 23.827mg/g，最符合朗缪尔等温模型。在 pH 效应实验中，在 pH 9 时发现 Sr 的吸附容量最高，通过温度、时间和选择性实验确定其吸附机制是自发的，通过与 Na 的竞争吸附，mag@BP 在短时间内达到吸附平衡，并具有较高的选择性。此外，还建立了吸附机制，该机制涉及到 BP 表面的离子交换（K）、与各种官能团的键合以及静电吸引。因此，mag@BP 是一种环保、低成本、可回收的吸附剂，适用于从水溶液中磁性去除 Sr。此外，与其他基于碳的吸附剂不同，它不会引起细胞毒性。
