MULTIELEMENT TRACE DETERMINATIONS IN AL2O3 CERAMIC POWDERS BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY WITH SPECIAL REFERENCE TO ONLINETRACE PRECONCENTRATION

The use of inductively coupled plasma mass spectrometry (ICP-MS) for t he determination of trace elements in Al2O3 powders is reported. Speci al interest is given to a preconcentration of the trace elements by on -line coupling of chromatography to ICP-MS. This is based on the compl exation of Co, Cu, Cr, Fe, Ga, Mn, Ni, V and Zn with hexamethylene-dit hiocarbamate (HMDC), their preconcentration on a C18 RP column by reve rsed phase liquid chromatography and their elution with CH3OH-H2O mixt ures. A direct coupling of the HPLC system to the ICP-MS has been real ized by high pressure pneumatic nebulization using desolvation. With t he chromatographic method developed, removal of the Al by at least 99% was achieved. For the trace elements V, Fe, Ni, Co, Cu and Ga, high a nd reproducible recoveries (ranging from 96-99%) were reached, The met hod developed has been shown to considerably enhance the power of dete ction as compared with direct procedures, namely down to 0.02-0.16 mu g/g for V and Fe, respectively. The possibilities of the method are sh own by the determinations of V, Mn, Fe, Ni, Co, Cu, Zn and Ga at the m u g/g level in Al2O3 powders. The accuracy of the method at the 0.06 t o 9.0 mu g/g level for Co and Fe, respectively, is demonstrated by a c omparison with results of independent methods from the literature.