Environment Functional Materials Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, Liaoning Province, PR China.
Water Res. 2013 Jul 1;47(11):3624-34. doi: 10.1016/j.watres.2013.04.023. Epub 2013 Apr 24.
By doping a proper amount of Mg(2+) (~10%) into α-Fe2O3 during a solvent thermal process, ultrafine magnesium ferrite (Mg0.27Fe2.50O4) nanocrystallites were successfully synthesized with the assistance of in situ self-formed NaCl "cage" to confine their crystal growth. Their ultrafine size (average size of ~3.7 nm) and relatively low Mg-content conferred on them a superparamagnetic behavior with a high saturation magnetization (32.9 emu/g). The ultrafine Mg0.27Fe2.50O4 nanoadsorbent had a high specific surface area of ~438.2 m(2)/g, and demonstrated a superior arsenic removal performance on both As(III) and As(V) at near neutral pH condition. Its adsorption capacities on As(III) and As(V) were found to be no less than 127.4 mg/g and 83.2 mg/g, respectively. Its arsenic adsorption mechanism was found to follow the inner-sphere complex mechanism, and abundant hydroxyl groups on its surface played the major role in its superior arsenic adsorption performance. It could be easily separated from treated water bodies with magnetic separation, and could be easily regenerated and reused while maintaining a high arsenic removal efficiency. This novel superparamagnetic magnesium ferrite nanoadsorbent may offer a simple single step adsorption treatment option to remove arsenic contamination from water without the pre-/post-treatment requirement for current industrial practice.
通过在溶剂热过程中掺杂适量的 Mg(2+)（约 10%）到α-Fe2O3 中，在原位自形成的 NaCl“笼”的辅助下，成功合成了超细微镁铁氧体（Mg0.27Fe2.50O4）纳米晶，以限制其晶体生长。它们的超细微尺寸（平均尺寸约为 3.7nm）和相对较低的 Mg 含量赋予了它们超顺磁性，具有高饱和磁化强度（32.9 emu/g）。超细微的 Mg0.27Fe2.50O4 纳米吸附剂具有高达 438.2 m2/g 的比表面积，并在近中性 pH 条件下对 As(III)和 As(V)均表现出优异的去除性能。其对 As(III)和 As(V)的吸附容量分别不低于 127.4mg/g 和 83.2mg/g。其砷吸附机理遵循内球络合机理，表面丰富的羟基在其优异的砷吸附性能中起主要作用。它可以通过磁分离很容易地从处理水体中分离出来，并且可以在保持高砷去除效率的同时很容易地再生和重复使用。这种新型超顺磁镁铁氧体纳米吸附剂可能为从水中去除砷污染提供了一种简单的单一吸附处理选择，而无需当前工业实践中的预处理/后处理要求。
