Improved Determination of Aluminium in Port Wine by Electrothermal Atomic Absorption Using Potassium Dichromate Chemical Modification and End-capped Graphite Tubes

Abstract

Improvements in the determination of aluminium in Port Wine by electrothermal atomic absorption spectrometry, namely in terms of precision and sensitivity, are described. Chemical modification with potassium dichromate was evaluated and compared with the performance of the most commonly used chemical modifiers. The behaviour of end-capped transverse heated graphite tubes (recently commercialized) and the standard tubes was compared. The developed method proved to be accurate and an improvement in sensitivity was achieved, when compared with that obtained without chemical modification and using standard graphite tubes.

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