OPTIMIZATION OF SLURRY NEBULIZATION INDUCTIVELY-COUPLED PLASMA ATOMIC EMISSION-SPECTROMETRY FOR THE ANALYSIS OF ZRO2-POWDER

The optimization and use of ICP-AES with slurry nebulization for the direct analysis of ZrO2-powder is described. The powder samples are dispersed in water, acidified to pH 2 and the slurry is fed into a Babington nebulizer. The effects of grain size, pH of the suspending medium and standing time on the stability of the slurry are discussed. For the optimization of the ICP operating conditions, a simplex technique is applied and for this purpose three types of objective functions were examined. Identical behaviour of slurries and solutions with the same matrix concentrations in the ICP-AES is achieved for powders with particle sizes lower than 10-mu-m; in the latter case calibration can be performed by standard addition with aqueous solutions. The detection limits for Al, B, Ca, Cu, Fe, Mg, Mn, Na, Ti, V. Y are 0.03-mu-g/g to 10-mu-g/g and the standard deviation is generally lower than 10%. Six commercially available ZrO2 powders are analyzed by slurry nebulization ICP-AES and the results were found to agree well with those obtained by ICP-AES after chemical decomposition of the samples.