Determination of chromium in steel by flame atomic-absorption spectrometry using a flow injection standard additions method

Abstract

The determination of chromium in steel by atomic-absorption spectrometry is briefly reviewed and the basis of the flow injection standard additions method explained, in which the novel configuration of using the sample as the carrier stream is employed. The effects of iron, fuel to oxidant ratio and dissolution procedure were investigated and a procedure is described that allows a conventional instrument-optimising strategy to be used, requires no releasing agents and uses pure chromium standard solutions. The selection of appropriate flow injection conditions is discussed in the light of the single well stirred mixing chamber model for dispersion. The application of the method is demonstrated by the analysis of six British Chemical Standard steels.

Automatic calibration in capillary electrophoresis

“…Thus, Tyson and Appleton [5] used concentration gradients for calibration in atomic absorption spectrometry. A completely continuous system was also used for analyte determination with periodic injections of standards of different concentration in order to implement a flow injection standard addition method [6]. A review of flow injection calibration techniques was published in 1988 [7].…”

Relocation of a Tubular Voltammetric Detector for Standard Addition in FIA

“…Tyson et al [2,3] presented a simple approach with a view to coupling the FIA/SAM, proposing a flow system in which the sample was placed in a position of infinite volume and the standard solutions were successively injected. Although simple, this approach had, as a disadvantage, the low sampling rate obtained, since the change of the sample implied the cleaning of the whole system.…”

Flow injection calibration techniques

“…In the simplest version a single line manifold is used. The method was first described by Tyson [21] and has been used for the determination of Ca in iron ore [22], Cr in steel [23], Ca in cement [24], Si in phos phoric acid [25] and Ba and Cr in river sediment and coal fly ash [26]. The last three examples are for ICP-AES of which the last two use a simplified version of Tyson's original method based on injection of a blank and a standard of concentration greater than that sought.…”