Analysis of trace mercury in water by solid phase extraction using dithizone modified nanometer titanium dioxide and cold vapor atomic absorption spectrometry
Analysis of trace mercury in water by solid phase extraction using dithizone modified nanometer titanium dioxide and cold vapor atomic absorption spectrometry作者机构:Faculty of Environmental Science and Engineering Guangdong University of Technology Guangzhou 510090 China Department of Chemical Engineering Maoming University Maoming 525000 China
出 版 物:《Rare Metals》 (稀有金属(英文版))
年 卷 期:2007年第26卷第6期
页 面:541-546页
核心收录:
学科分类:07[理学] 0806[工学-冶金工程] 0805[工学-材料科学与工程(可授工学、理学学位)] 0703[理学-化学] 0702[理学-物理学]
基 金:the Natural Science Foundation of the Department of Education Guangdong Province China (No. 02025)
主 题:analytical chemistry mercury solid-phase extraction TiO2 nanoparticle cold vapor atomic adsorption spectrometry (CVAAS)
摘 要:A new method for analysis of trace mercury in water samples was developed, based on the combination of preconcentration/separation using dithizone-modified nanometer titanium dioxide (TiO2) as a solid phase extractant and determination by cold vapor atomic adsorption spectrometry (CVAAS). Dithizone was dissolved with alcohol and loaded on the surface of nano-sized TiO2 powders by stirring. The static adsorption behavior of Hg^2+on the dithizone-modified nanoparficles was investigated in detail. It was found that excellent adsorption ratio for Hg^2+ could be obtained in the pH range of 7-8 with an oscillation time of 15 rain, and a 5 mL of 3.5 mol·L^-1 HCI solution could quantitatively elute Hg^2+ from nanometer TiO2 powder. Common coexisting ions caused no obvious influence on the determination of mercury. The mechanisms for the adsorption and desorption were discussed. The detection limit (30) for Hg^2+ was calculated to be 5 ng·L^-1. The proposed method was applied to the determination of Hg^2+ in a mineral water sample and a Zhujiang River water sample. By the standard addition method, the average recoveries were found to be 94.4%-108.3% with RSD (n = 5) of 2.9%-3.5%.