Article
Simultaneous determination of lead, nickel, tin and copper in aluminium-base alloys using slurry sampling by electrical discharge and multielement ETAAS
Autor
Carrión, Nereida
Itriago, Ana M.
Alvarez, María de los Angeles
Eljuri, Elías
Institución
Resumen
The simultaneous multielement determination of Pb, Sn, Ni and Cu in aluminium alloys by electrothermal atomic
absorption spectrometry (ETAAS) was performed by a quick method using slurry sampling. The metallic colloidal
slurries were obtained by an electrical discharge operated in liquid medium. In this work, the effects of aluminium were
evaluated and the results show that it causes a strong retention of Pb, Ni and Cu at low pyrolysis temperatures which is
overcome by employing high pyrolysis temperatures. Aluminium also significantly improves the thermal stabilisation of
Pb and Sn, it being possible to reach pyrolysis temperatures of 1100 and 1300 8C, respectively. Such stabilisation
indicates that the performance of aluminium as a matrix modifier for Pb is better than that obtained using phosphate
and magnesium nitrate without substantial changes of the figures of merit. The effects of aluminium on the atomisation
characteristics of the elements and those coming from the simultaneous multielement determination on the figures of
merit of the elements are also discussed. In this work, a calibration procedure involving a matrix matching method with
aqueous aluminium standards is proposed as a simple and efficient way to solve the inconveniences originated by the
aluminium matrix. The proposed method was applied to the simultaneous multielement determination of several
aluminium-base alloy standards giving results well within the recommended values.