DETERMINATION OF ARSENIC, CHROMIUM, AND NICKEL IN SLURRIED TALC SAMPLES BY ELECTROTHERMAL AAS

An analytical procedure was established for the determination of arsen ic, chromium, and nickel in talc samples (Mg-3 [(OH)(2)/Si-4 O-10]), a nd, for comparison, one sample of silica gel by using slurry sampling electrothermal atomization atomic absorption spectrometry with a conti nuum source background corrector. Two techniques of slurry ultrasonic agitation are described using a handheld ultrasonic probe and an ultra sonic bath. The ratio of the amount of analyte found in the liquid pha se to the total amount of analyte in the slurries was investigated. Th e calibration was performed using aqueous standards but for the determ ination of arsenic, the method of standard additions was used. The res ults of As, Cr, and Ni determination are compared with the results of an independent analytical technique. The evaluation of the analytical results indicate that the repeatability of both techniques of slurry m ixing and homogenization is comparable and the results are in good agr eement with those obtained by Liquid sampling ETAAS or ICP-OES.