Solid-phase extraction of lead(II) ions using multiwalled carbon nanotubes grafted with tris(2-aminoethyl)amine

Multiwalled carbon nanotubes were grafted with tris(2-aminoethyl)amine (MWCNTs-TAA) and employed for solid phase extraction and preconcentration of trace lead ions prior to its determination by inductively coupled plasma optical emission spectrometry. The material was characterized by FT-IR and Raman spectroscopy, thermosgravimetric and elemental analysis. The effects of pH value, shaking time, sample volume, elution conditions and potentially interfering ions were investigated. Under the optimum conditions, the maximum adsorption capacity is 38 mg g(-1) of Pb(II), the detection limit is 0.32 ng mL(-1), the enrichment factor is 60, and the relative standard deviation is 3.5% (n = 6). The method has been applied to the preconcentration of trace amounts of Pb(II) in environmental water samples with satisfactory results.