STUDY OF CERIUM(IV) AND CERIUM(IV)-PALLADIUM(II) AS CHEMICAL MODIFIERS IN ELECTROTHERMAL ATOMIZATION ATOMIC-ABSORPTION SPECTROPHOTOMETRY

Cerium (IV) in the forms (NH4)2Ce(NO3)6 and Ce (IV)-Pd (II) has been evaluated as a chemical modifier for 24 and 17, respectively, analyte elements of high and moderate volatility. The maximum pretreatment temperatures (°C) in the presence of 20 μg Ce (IV) and 20 μg Ce (IV)-4 μg Pd (II) are, respectively: Ag (900 and 900), As (1200 and 1600), Au (900 and 850), Bi (800 and 1200), Cd (800 and 850), Co (1300), Cr (1300), Cu (1100 and 1100), Fe (1300), Ga (950 and 1300), Ge (1000 and 1250), Hg (260), In (900 and 1200), Mn (1200), Ni (1200), P (1350 and 1400), Pb (950 and 1100), Pd (1300), Sb (1100 and 1400), Se (1200 and 1200), Sn (1100 and 1500), Te (800 and 1100), Tl (800 and 900), and Zn (850 and 900). The effect of atomization surface (electrographite, pyrographite, or TaC-coating) has been examined and possible mechanisms of the thermal stabilization are discussed. © 1990.