文献类型：期刊文献

英文题名：Modified mesoporous silica materials for on-line separation and preconcentration of hexavalent chromium using a microcolumn coupled with flame atomic absorption spectrometry

作者：Wang, Zheng[1];Fang, Dong-Mei[1,2];Li, Qing[1,2];Zhang, Ling-Xia[1];Qian, Rong[1];Zhu, Yan[1];Qu, Hai-Yun[1];Du, Yi-Ping[2]

机构：[1]Chinese Acad Sci, Shanghai Inst Ceram, Shanghai 200050, Peoples R China;[2]E China Univ Sci & Technol, Shanghai 200237, Peoples R China

年份：2012

卷号：725

起止页码：81

外文期刊名：ANALYTICA CHIMICA ACTA

收录：;EI(收录号：20121714960259);WOS:【SCI-EXPANDED(收录号:WOS:000303292100010)】；

基金：This project was supported by National Natural Science Foundation of China (21175145), the Science and Technology Commission of Shanghai Municipality (09142201800) and the Startup Funding of Chinese Academy of Sciences (O87YQ1110G).

语种：英文

外文关键词：Modified mesoporous silica; Hexavalent chromium; Trivalent chromium; Solid phase extraction; Flame atomic absorption spectrometry

摘要：A modified SBA-15 mesoporous silica material NH2-SBA-15 was synthesized successfully by grafting gamma-aminopropyl-triethoxysilane. The material was characterized using transmission electron microscopy (TEM) and Fourier transform infrared/Raman (FT-IR/Raman) spectroscopy. and used for the first time in a flow injection on-line solid phase extraction (SPE) coupled with flame atomic absorption spectrometry (FAAS) to detect trace Cr (VI). Effective sorption of Cr (VI) was achieved at pH 2.0 with no interference from Cr (III) and other ions and 0.5 mol L-1 NH3 center dot H2O solution was found optimal for the complete elution of Cr (VI). An enrichment factor of 44 and was achieved under optimized experimental conditions at a sample loading of 2.0 mL min(-1) sample loading (300 s) and an elution flow rate of 2.0 mL min(-1) (24 s). The precision of the 11 replicate Cr (VI) measurements was 2.1% at the 100 mu g L-1 level with a detection limit of 0.2 mu g L-1 (3 s, n = 10) using the FAAS. The developed method was successfully applied to trace chromium determination in waste water. The accuracy was validated using a certified reference material of riverine water (GBW08607). (c) 2012 Elsevier B.V. All rights reserved.