Hebei Center for Ecological and Environmental Geology Research, Hebei GEO University, Shijiazhuang, China.
School of Water Resources and Environment, Hebei GEO University, Shijiazhuang, China.
PLoS One. 2024 Oct 11;19(10):e0311239. doi: 10.1371/journal.pone.0311239. eCollection 2024.
To remove phosphate from water, a novel Fe-doped ZIF-8 was synthesized as a superior adsorbent. The Fe-doped ZIF-8 was fully characterized using different characterization techniques and it was found that the as-prepared Fe-doped ZIF-8 (denoted as ZIF-(2Zn:1Fe)) showed a polyhedral morphology with a large specific surface area of 157.64 m2/g and an average pore size of 3.055 nm. Analyses using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction showed that Fe atoms were successfully incorporated into the ZIF-8 skeleton. Batch experiments demonstrated that the molar ratio of Fe and Zn has effects on phosphate adsorption. The adsorption kinetics conformed to a pseudo-second-order model with a high correlation coefficient (R2 = 0.9983). The adsorption isotherm matched the Langmuir model (R2 = 0.9994) better than the Freundlich model (R2 = 0.7501), suggesting that the adsorption of phosphoric acid by ZIF-(2Zn:1Fe) can be classified as a chemisorption on a homogeneous surface. The adsorption amount was 38.60 mg/g. It was found that acidic environments favored the adsorption reaction and the best adsorption was achieved at an initial pH of 2. Inhibition of adsorption by common anions is NO3-> CO32-> SO42-> Cl-. Characterization results indicate that the main mechanism of adsorption is surface complexation interactions.
为了去除水中的磷酸盐，合成了一种新型的 Fe 掺杂 ZIF-8 作为优异的吸附剂。通过不同的表征技术对 Fe 掺杂 ZIF-8 进行了充分的表征，发现所制备的 Fe 掺杂 ZIF-8（表示为 ZIF-（2Zn：1Fe））呈现多面体形貌，具有 157.64 m2/g 的大比表面积和 3.055nm 的平均孔径。傅里叶变换红外（FTIR）光谱和 X 射线衍射分析表明，Fe 原子成功地掺入到 ZIF-8 骨架中。批量实验表明，Fe 和 Zn 的摩尔比对磷酸盐吸附有影响。吸附动力学符合准二级模型，相关系数（R2 = 0.9983）较高。吸附等温线更符合 Langmuir 模型（R2 = 0.9994），而不是 Freundlich 模型（R2 = 0.7501），表明 ZIF-（2Zn：1Fe）对磷酸的吸附可以归类为均匀表面的化学吸附。吸附量为 38.60mg/g。发现酸性环境有利于吸附反应，最佳吸附在初始 pH 值为 2 时达到。常见阴离子对吸附的抑制作用为 NO3->CO32->SO42->Cl-。表征结果表明，吸附的主要机制是表面络合相互作用。
