N-doped porous carbon with magnetic particles formed in situ for enhanced Cr(VI) removal
N-doped porous carbon with magnetic particles formed in situ for enhanced Cr(VI) removal
复制标题
具有原位形成的磁性颗粒的 N 掺杂多孔碳，用于增强 Cr(VI) 的去除
DOI：
10.1016/j.watres.2012.10.056
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发表时间：
2013-08-01
期刊：
影响因子：
12.8
通讯作者：
Ma, Jun
中科院分区：
文献类型：
--
作者：
Li, Yao;Zhu, Shenmin;Ma, Jun
通过简单的浸渍、聚合和焙烧制备了一种新型的原位形成磁性纳米颗粒的N掺杂多孔炭(RHC-MAG-CN)。RHC-MAG-CN中的氮以石墨层的形式存在，其组成为CN。所制备的纳米复合材料的比表面积为1136m(2)g(-1)，其中含有18.5wt%的磁性纳米粒子(Fe3O4和Fe)，饱和磁化强度(Ms)为22emu/g。作为吸附剂，RHC-MAG-CN对铬(VI)的吸附非常迅速，在10min内，当吸附剂量为2g L-1时，稀溶液中92%的铬(VI)可以被脱除。较高的吸附容量(16mgg~(-1))与表面物理吸附和络合反应产生的化学吸附的协同作用有关。重要的是，RHC-MAG-CN中的碱性CNS增加了它的负电荷密度，同时也增加了对金属阳离子的吸附，如在酸性溶液中铬(VI)还原生成的Cr3+。磁性纳米颗粒的形成不仅为铬(VI)的吸附提供了配位，而且表现出良好的磁分离性能。(C)2013爱思唯尔有限公司。保留所有权利。
A newly designed N-doped porous carbon with magnetic nanoparticles formed in situ (RHC-mag-CN) was fabricated through simple impregnation then polymerization and calcination. The doped nitrogen in RHC-mag-CN was in the form of graphite-type layers with the composition of CN. The resultant nanocomposite maintained a high surface area of 1136 m(2) g(-1) with 18.5 wt% magnetic nanoparticles (Fe3O4 and Fe) inside, which showed a saturation magnetization (Ms) of 22 emu/g. When used as an adsorbent, the RHC-mag-CN demonstrated a very quick adsorption property for the removal of Cr(VI), during which 92% of Cr(VI) could be removed within 10 min for dilute solutions at 2 g L-1 adsorbent dose. The high adsorption capacity (16 mg g(-1)) is related to the synergetic effects of physical adsorption from the surface area and chemical adsorption from complexation reactions between Cr(VI) and Fe3O4. Importantly, the basic CNs in RHC-mag-CN increase its negative charge density and simultaneously increase the adsorption of metallic cations, such as Cr3+ formed in the acid solution from the reduction of Cr(VI). The formation of magnetic nanoparticles inside not only supplies complexing sites for the adsorption of Cr(VI), but also shows perfect magnetic separation performance from aqueous solution. (c) 2013 Elsevier Ltd. All rights reserved.