Zero-valent iron particles embedded on the mesoporous silica-carbon for chromium (VI) removal from aqueous solution
Zero-valent iron particles embedded on the mesoporous silica-carbon for chromium (VI) removal from aqueous solution
复制标题
嵌入介孔硅碳上的零价铁颗粒用于从水溶液中去除铬（VI）
DOI：
10.1007/s11051-016-3582-z
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发表时间：
2016
影响因子：
2.5
通讯作者：
Zhang Xianming
中科院分区：
文献类型：
--
作者：
Xiong Kun;Gao Yuan;Zhou Lin;Zhang Xianming
在高温碳化和还原条件下，将纳米级零价铁（nZVI）颗粒嵌入介孔二氧化硅-碳（MSC）壁上，用于去除水溶液中的铬（VI）。通过粉末 X 射线衍射、透射电子显微镜和 N2 吸附和解吸对 nZVI-MSC 的结构和织构特性进行了表征。结果表明，nZVI-MSC具有高度有序的介孔结构和大的表面积，与MSC没有区别。与负载在活性炭上的载体 MSC 和铁颗粒 (nZVI/AC) 相比，nZVI-MSC 表现出更高的 Cr(VI) 去除效率，约为 98%。去除过程遵循伪一阶模型。 nZVI-MSC如此优异的性能可归因于MSC壁上嵌入的大表面和铁颗粒，与MSC形成紧密接触。据认为，这一特性可能会在铁颗粒和 MSC 的界面上形成某种微电极，从而阻止表面金属氧化物的形成，并为 Cr(VI) 的去除提供新鲜的 Fe 表面。
Nanoscale zero-valent iron (nZVI) particles were embedded on the walls of mesoporous silica–carbon (MSC) under the conditions of high-temperature carbonization and reduction and used to remove chromium (VI) from aqueous solution. The structure and textural properties of nZVI–MSC were characterized by the powder X-ray diffraction, transmission electron microscopy and N2adsorption and desorption. The results show that nZVI–MSC has highly ordered mesoporous structure and large surface area, indistinguishable with that of MSC. Compared with the support MSC and iron particles supported on the activated carbon (nZVI/AC), nZVI–MSC exhibited much higher Cr(VI) removal efficiency with about 98 %. The removal process obeys a pseudo first-order model. Such excellent performance of nZVI–MSC could be ascribed to the large surface and iron particles embedded on the walls of the MSC, forming an intimate contact with the MSC. It is proposed that this feature might create certain micro-electrode on the interface of iron particles and MSC, which prevented the formation of metal oxide on the surface and provided fresh Fe surface for Cr(VI) removal.