Uso da análise exploratória de dados na avaliaçã o de modificadores químicos para determinação direta e simultânea de metais em álcool combustível por GFAAS

Abstract

The aim of this work was to employ the exploratory analysis, in this case, the principal component analysis (PCA) as an alternative tool in the evaluation of chemical modifiers for direct and simultaneous determination of Al, As, Cu, Fe, Mn and Ni in ethanol fuel by graphite furnace atomic absorption spectrometry (GFAAS). The evaluated chemical modifiers were Pd(NO 3) 2 + Mg(NO 3) 2; W/Rh; W+ co-injection of Pd(NO 3) 2 + Mg(NO 3) 2 and 30 samples of ethanol fuel were used for each one. As experimental data were used the results of the addition and recovery tests. The use of the principal component analysis allowed the separation of the different modifiers in function of the recovery range of the analyte. The modifier W+ co-injection of Pd(NO 3) 2 + Mg(NO 3) 2 showed up as the higher positive correlation specie, because shows the higher recovery level, and so, was selected for the development of methodology for direct and simultaneous determination of Al, As, Cu, Fe, Mn and Ni in ethanol fuel by GFAAS.