Analysis of high purity water by flameless atomic-absorption spectroscopy. Part I. The use of an automated sampling system

Abstract

An apparatus is described that enables fully automatic stream sampling and sample injection to be carried out when using the graphite-tube method of analysis in conjunction with atomic-absorption spectroscopy. Multiple aliquots of solution can be introduced automatically, with a drying step between each introduction. The concentration sensitivity of the method is thus increased even further, but without encountering the difficulties associated with the manual injection of multiple aliquots. In addition, a significant improvement in precision is obtained when using the automatic sampling and injection system rather than manual sampling.

The apparatus has been designed as part of a system to determine simultaneously a number of elements at levels of parts per 10⁹ and below. Results for precision are presented for the determination of cobalt, chromium, copper, iron, manganese and nickel, and results for sensitivity are given for these and additional representative elements.