Analysis of trace mercury in water by solid phase extraction using dithizone modified nanometer titanium dioxide and cold vapor atomic absorption spectrometry
来源期刊:Rare Metals2007年第6期
论文作者:MA Xiaoguo), HUANG Bei), and CHENG Meiqing) ) Faculty of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou , China ) Department of Chemical Engineering, Maoming University, Maoming , China
文章页码:541 - 546
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 Hg2+on the dithizone-modified nanoparticles was investigated in detail. It was found that excellent adsorption ratio for Hg2+ could be obtained in the pH range of 7-8 with an oscillation time of 15 min, and a 5 mL of 3.5 molL1 HCl solution could quantitatively elute Hg2+ 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 (3σ) for Hg2+ was calculated to be 5 ngL1. The proposed method was applied to the determination of Hg2+ 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%.
MA Xiaoguo1), HUANG Bei1), and CHENG Meiqing2) 1) Faculty of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510090, China 2) Department of Chemical Engineering, Maoming University, Maoming 525000, China
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 Hg2+on the dithizone-modified nanoparticles was investigated in detail. It was found that excellent adsorption ratio for Hg2+ could be obtained in the pH range of 7-8 with an oscillation time of 15 min, and a 5 mL of 3.5 molL1 HCl solution could quantitatively elute Hg2+ 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 (3σ) for Hg2+ was calculated to be 5 ngL1. The proposed method was applied to the determination of Hg2+ 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%.
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