Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10559107 | Spectrochimica Acta Part B: Atomic Spectroscopy | 2005 | 6 Pages |
Abstract
A simple and inexpensive laboratory-built flow injection vapor generation system coupled to atomic absorption spectrometry (FI-VG AAS) for inorganic and total mercury determination has been developed. It is based on the vapor generation of total mercury and a selective detection of Hg2 + or total mercury by varying the temperature of the measurement cell. Only the inorganic mercury is measured when the quartz cell is at room temperature, and when the cell is heated to 650 °C or higher the total Hg concentration is measured. The organic Hg concentration in the sample is calculated from the difference between the total Hg and Hg2 + concentrations. Parameters such as the type of acid (HCl or HNO3) and its concentration, reductant (NaBH4) concentration, carrier solution (HCl) flow rate, carrier gas flow rate, sample volume and quartz cell temperature, which influence FI-VG AAS system performance, were systematically investigated. The optimized conditions for Hg2 + and total Hg determinations were: 1.0 mol lâ 1 HCl as carrier solution, carrier flow rate of 3.5 ml minâ 1, 0.1% (m/v) NaBH4, reductant flow rate of 1.0 ml minâ 1 and carrier gas flow rate of 200 ml minâ 1. The relative standard deviation (RSD) is lower than 5.0% for a 1.0 μg lâ 1 Hg solution and the limit of quantification (LOQ, 10 s) is 55 ng gâ 1. Certified samples of dogfish muscle (DORM-1 and DORM-2) and non-certified fish samples were analyzed, using a 6.0 mol lâ 1 HCl solution for analyte extraction. The Hg2 + and CH3Hg+ concentrations found were in agreement with certified ones.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Luiz Eduardo Kaercher, Fabiane Goldschmidt, José Neri Gottfried Paniz, Ãrico Marlon de Moraes Flores, Valderi Luiz Dressler,