Solid phase extraction of trace amounts of palladium ions using multiwalled carbon nanotube modified by N,N’-bis(2-hydroxy-benzylidene)-2,2’(aminophenylthio) ethane prior to determination by flame atomic absorption spectrometry
Multiwalled carbon nanotubes modified with N,N’-bis(2-hydroxybenzylidene)-2,2’(aminophenylthio) ethane have been developed for the selective separation and/or preconcentration of trace amounts of Pd(II) in aqueous medium. Parameters including pH of aqueous solution, flow rates, the amount of ligand and the type of stripping solvents were optimized. It was found that the sorption is quantitative in the pH range (1.5-4), whereas quantitative desorption occurs instantaneously with 3.0 mL of 0.3 M Na2SO3. Linearity was maintained between 0.01 to 22 mg mL-1 for Pd in the final solution. The breakthrough volume was greater than 1800 mL with an enrichment factor of more than 600 and 6.0 mg L−1 detection limit (3s, n = 10). The effects of various ions interferences on the percent recovery of palladium ion were studied. The method was successfully applied to the determination of palladium ion in environmental samples.
KEY WORDS: Multiwalled carbon nanotubes, Preconcentration, Palladium(II) determination
Bull. Chem. Soc. Ethiop. 2012, 26(1), 19-26.