DETERMINATION OF ANTIMONY, ARSENIC, BISMUTH, SELENIUM, TELLURIUM AND TIN BY LOW-PRESSURE ATOMIC-ABSORPTION SPECTROMETRY WITH A QUARTZ TUBE FURNACE ATOMIZER AND HYDRIDE GENERATION WITH AIR ADDITION

A new method has been developed for the determination of antimony, ars enic, bismuth, selenium, tellurium and tin by hydride generation-atomi c absorption spectrometry in an electrically heated quartz tube furnac e under sub-atmospheric pressure. The hydride generator, operating at a pressure lower than atmospheric, is used to generate and collect the hydrides of these elements. A certain volume (at atmospheric pressure ) of air is then added to the generator after the formation of the vol atile hydride. The gaseous mixture of the hydride and air is drawn int o an evacuated, heated quartz tube by a vacuum pump. The proposed meth od gives improved sensitivities and detection limits.