Radiotracer investigation of hydride trapping efficiency within a graphite furnace

Efficiencies of hydride generation and in situ trapping in the transversely heated graphite furnace by using Pd modifier were studied for selenium hydride, arsine and stibine by means of the radiotracers Se-75, As-76 and Sb-122. The influence of four experimental parameters, i.e. Pd modifier mass, trapping temperature, carrier gas flow rate and the distance of the hydride introduction capillary from the platform surface, on selenium hydride trapping efficiency was investigated by both the radiotracer technique and atomic absorption spectrometry. For selenium hydride, stibine and arsine, generation efficiencies of 78.1 +/- 1.5%, 94 +/- 4% and close to 100%, respectively, were obtained. For selenium hydride, complete trapping was achieved within a broad variation range of the four experimental parameters studied. At experimental parameters optimized for selenium hydride trapping, the overall efficiencies of hydride generation and trapping for stibine and arsine were 87 +/- 4% and 99 +/- 2%, respectively. (C) 1997 Elsevier Science B.V.