IMPROVED DESIGN AND OPTIMIZATION OF AN ELECTROTHERMAL VAPORIZATION SYSTEM FOR INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY

A horizontal graphite tube furnace for electrothermal vaporization of samples and introduction of the evolved material in the form of an aer osol into an ICP source is described. The most characteristic differen ce from the commercial (Perkin Elmer) system is that a glass cylinder is used around the graphite elements, and this enclosure makes possibl e the transportation of the evolved product exiting upward through the sample injection port. The effects of the following parameters have b een investigated on the cadmium emission signal: furnace temperature, flow rate of the internal and the external furnace gases (argon), use of sample boat, and use of solution phase additive (sodium selenite) a nd gas phase additives (carbon tetrachloride and toluene vapor). (C) 1 995 Academic Press, Inc.