Preconcentration system for cadmium and lead determination in environmental samples using polyurethane foam/Me-BTANC

• Published in: Journal of hazardous materials 2006-08, Vol.136 (3), p.757-762
• Main Authors: Gama, Ednilton Moreira, da Silva Lima, Adriana, Lemos, Valfredo Azevedo
• Format: Article
• Language: English
• Subjects: Adsorption; Animals; Applied sciences; Azo Compounds - chemistry; Cadmium; Cadmium - analysis; Calibration; Chemical engineering; Environmental Pollutants - analysis; Exact sciences and technology; Fishes; Food Analysis; Hydrodynamics of contact apparatus; Hydrogen-Ion Concentration; Indicators and Reagents; Lead; Lead - analysis; Me-BTANC; Meat - analysis; Naphthalenesulfonates - chemistry; Online Systems; Pollution; Polyurethane foam; Polyurethanes; Preconcentration; Spectrophotometry, Atomic; Spinacia oleracea; Spinacia oleracea - chemistry; Water Supply - analysis
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2006.01.015

In this work, polyurethane foam (PUF) loaded with 2-(6′-methyl-2′-benzothiazolylazo)chromotropic acid (Me-BTANC) was packed in a minicolumn and it was used in an on-line preconcentration system for cadmium and lead determination. Optimum hydrodynamic and chemical conditions for metal sorption were investigated. The effects of several foreign substances on the adsorption of cadmium and lead were also reported. The enrichment factor obtained was 37 (Cd and Pb) for 180 s preconcentration time. The proposed procedures allowed the determination of metals with detection limits (3 σ) of 0.80 and 3.75 μg L −1 (0.10 and 0.47 μg g −1 of solid sample) for cadmium and lead, respectively. The precision of the procedures was also calculated: 3.1 (Cd 10 μg L −1) and 4.4% (Pb 100 μg L −1). The accuracy of the procedure was checked by analysis of the certified reference materials Spinach Leaves and Fish Tissue. Cadmium and lead contents in environmental samples (black tea, spinach leaves, natural and tap water) were determined by applying the proposed procedure.