Heating characteristics of glassy carbon tubes used in electrothermal atomization-atomic absorption spectrometry

Abstract

Glassy carbon tubes of standard dimensions can be heated up to 3200 K with minor modification to the power supply that is used to heat graphite tubes. Under standard conditions the heating rates of graphite and glassy carbon are about the same. An increased voltage is required to heat glassy carbon tubes lo the same furnace temperature. The power consumption of the various tubes is shown to be equal. Similar analytical sensitivity can be obtained with glassy carbon and pyrolytically coated graphite lubes, provided that the same heating rates can be realized. The glassy carbon material supplied by Tokai shows high blank signals for Al, Fe and Si and blank signals are also observed for Mn, Ti and V. The purity of the glassy carbon from Le Carbone-Lorraine is much better. However, a glassy carbon material of higher purity should be developed for use in ETA-AAS.