Preconcentration of trace elements by using 1-(2-pyridylazo)-2-naphthol functionalized Amberlite XAD-1180 resin and their determination by FAAS

摘要

In this study, Amberlite XAD-1180 resin functionalized by 1-(2-pyridylazo)-2-naphthol ( PAN) was synthesized and the resulting resin was used for preconcentration of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Cd(II) and Pb(II) elements present at trace levels in different matrices. For this purpose, the copolymer was nitrated, reduced to the corresponding amine, converted to the diazonium salt with nitrite and reacted with PAN to produce the XAD-1180-PAN chelating resin. For the described method, the effect of some analytical parameters, such as pH, sample volume, resin amount, flow rates of uptake and stripping, volume and type of eluent, on the recovery of the trace elements was investigated. The metals retained on the XAD-1180-PAN resin were eluted by 2 mol L-1 HNO3. The influence of matrix ions, i.e., Na(I), K(I), Ca(II) and Mg(II), on the recovery of trace elements was also examined by using the developed method when they occurred both individually and together. The repeatability of the method at the optimum conditions determined experimentally was investigated. The recovery values for all the elements, except for Cr(III), were found to be >= 92% and the relative standard deviation was <= 8.5%. The 3s/b detection limits for Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Cd(II) and Pb(II) were found to be 4.1, 0.13, 2.7, 1.2, 0.19, 0.06 and 0.13 mu g L-1, respectively. The developed method was utilized for preconcentration and determination of Mn(II), Fe(III), Ni(II), Cu(II), Cd(II) and Pb(II) in tap water, rain water, and stream water, and of Ni(II), Cd(II) and Pb(II) in a certified reference material (RM 8704 Buffalo river sediment) by flame atomic absorption spectrometry (FAAS).