Characterization of lead oxides by laser microprobe coupled with mass spectrometry in resonant and non-resonant mode : Application to amorphous silicates containing lead

The laser microprobe coupled with mass spectrometry (LMMS) is used to determine the oxidation state of amorphous silicates containing lead. In positive mode, the fingerprint spectra obtained for mixtures of lead oxides and quartz sand are compared with those obtained by the analysis of microparticles of PbO and PbO 2 oxides. For these, the effect of the ionization laser wavelength is illustrated: the use of resonant desorption/ionization processes (357.2 and 283.3 nm) allows to distinguish both oxides. Applied to glass dust (lead oxide containing high refractive index:amorphous) coming from finishing workrooms of a glass manufacture, this in situ analytical method using the 283.3 nm resonant wavelength leads to LMMS fingerprint spectra which present strong similarities with PbO spectra La microsonde laser couplee a la spectrometrie de masse (LMMS) est utilisee afin de determiner la valence du plomb contenu dans des verres silicates. En mode positif, l'empreinte spectrale des melanges plomb-sable est comparee a celle des composes PbO et PbO 2 . Pour ces derniers, l'effet de la longueur d'onde d'ionisation est illustre: l'utilisation du processus de desorption/ionisation resonnant (357,2 et 283,3 mm) nous permet de distinguer les deux oxides. Appliquee aux pousssieres emises dans les ateliers de finition des cristalleries, cette methode d'analyse in situ conduit a la longueur d'onde resonante 283,3 nm, des empreintes spectrales du plomb presentant de nombreuses similitudes avec celles de PbO.