Determination of trace elements in high-purity aluminum by solid-phase extraction/ICP-MS

Abstract

We attempted a simple pretreating method consisting of solid-phase extraction using bonded silica with benzenesulfonic acid (SCX) as the solid-phase sorbent to determine trace elements in pure aluminum samples by means of inductively coupled plasma mass spectrometry (ICP-MS). The acidic solutions were prepared by dissolving samples in sodium hydroxide, and subsequently adding nitric acid. The analytes could be separated as 1,10-phenanthroline chelate from the matrix by solid-phase extraction after adjusting the pH and adding 1,10-phenanthroline. The optimum condition for aluminum separation was pH 3 and 15 ml of 0.01 M 1,10-phenanthroline. As the eluant, 15 ml of 6 M nitric acid was used. In this method, some trace elements, such as Fe, Ni, Co, Cu, Zn, Ag, Cd, Ga and In, were determined by ICP-MS using the eluate. The limits of detection in ng/g were Fe, 0.69; Ni, 0.89; Co, 0.38; Cu, 3.66; Zn, 1.68; Ag, 0.62; Cd, 1.74; Ga, 1.13 and In, 0.08 ppb.