Determination of cadmium in river water samples by flame AAS after on-line preconcentration in mini-column packed with 2-aminothiazole-modified silica gel

• Autor(a) principal: Alcântara, Ilton L. [UNESP]
• Data de Publicação: 2004
• Outros Autores: Roldan, Paulo S. [UNESP], Castro, Gustavo R. [UNESP], Moraes, Fabrício V. [UNESP], Silva, Fábio A. [UNESP], Padilha, Cilene C. F. [UNESP], Oliveira, Jorge D. [UNESP], Padilha, Pedro M. [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.2116/analsci.20.1029; http://hdl.handle.net/11449/67792
• topic: 2 aminothiazole derivative; cadmium; hydrochloric acid; river water; silica gel; adsorption; aqueous solution; atomic absorption spectrometry; calibration; combustion; concentration (parameters); elution; flame atomic absorption spectrometry; nebulizer; online system; pH; sensitivity and specificity; water sampling; Cadmium; Calibration; Hydrochloric Acid; Hydrogen-Ion Concentration; Ions; Models, Chemical; Silicon Dioxide; Spectrophotometry; Spectrophotometry, Atomic; Spectrophotometry, Infrared; Thiazoles; Time Factors; Water

A rapid and sensitive method was developed to determine trace levels of Cd2+ ions in an aqueous medium by flame atomic absorption spectrometry, using on-line preconcentration in a mini-column packed with 100 mg of 2-aminothiazol modified silica gel (SiAT). The Cd2+ ions were sorbed at pH 5.0. The preconcentrated Cd2+ ions were directly eluted from the column to the spectrometer's nebulizer-burner system using 100 μL of 2 mol L-1 hydrochloric acid. A retention efficiency of over 95% was achieved. The enrichment factor (calculated as the ratio of slopes of the calibration graphs) obtained with preconcentrations in a mini-column packed with SiAT (A = -1.3 × 10-3 + 1.8 × 10-3 [Cd2+]) and without preconcentrations (A = 4 × 10-5 + 3.5 × 10-3[Cd2+]), was 51 and the detection limit calculated was 0.38 μg L-1. The preconcentration procedure was applied to determine trace levels of Cd in river water samples. The optimum preconcentration conditions are discussed herein.