Analytical results for glassy carbon tubes in electrothermal atomization atomic absorption spectrometry at high temperatures

Abstract

A new type of glassy carbon tube has been tested for use in ETA-AAS at high temperatures. These tubes can be heated as fast as common graphite and pyrolytically coated graphite tubes and they require the same power to reach an equal final temperature. However, glassy carbon tubes of standard dimensions require some modification to the power supply. With respect to the analytical sensitivity using wall-sampling techniques, glassy carbon is similar to pyrolytically coated graphite tubes for the non-refractory elements and similar to standard graphite tubes for the refractory elements. The interference of perchloric acid on the determination of aluminium is reduced when a glassy carbon tube and platform are used. The results of a preliminary study of the lifetime of glassy carbon tubes are promising. At an atomization temperature of 3100K, the glassy carbon tubes can be used for about 500 firings.