Determination of As, Bi, Pb, Sb, and Sn in Copper, Nickel, and Alloys on Their Basis by Electrothermal Atomic Absorption Spectrometry

Alloys based on copper and nickel are widely used in various industries. Their properties directly depend on existing impurities and dopants. Therefore, monitoring of these components in alloy compositions remains an urgent issue. This work studies analytical characteristics of the methods used for determination of As, Bi, Pb, Sb, and Sn in copper, nickel, and alloys on their basis by electrothermal atomic absorption spectrometry (ETAAS) with line spectrum sources, deuterium background correction, and longitudinal heating by graphite tube (LR-LS ETAAS) and high-resolution ETAAS with continuous spectrum source and transversally heated atomizer (HR-CS ETAAS). The parameters of the atomizer temperature program have been optimized for both variants of atomic absorption spectrometry. The interfering influence of the matrix of the considered samples has been revealed: Cu and Ni significantly distort analytical signals and cause significant background absorption. It has been established that, in the course of plotting of calibrating dependences using LR-LS ETAAS, it is necessary to add a matrix component to calibrating solutions, and in the case of HR-CS ETAAS, it is possible to exclude the matrix addition without an increase in the error of analysis. The developed procedures have been verified upon analysis of high-purity copper and nickel, as well as standard alloys based on VSM14-5 copper (crude copper), VSM14-6 (bronze) and VSN2-2 nickel. The achieved detection limits of elements using HR-CS ETAAS amount to n x 10(-5)%. For LR-LS ETAAS, this value is an order of magnitude higher. The determination of lower contents of elements in such materials should involve separation of the matrix.