BEHAVIOR OF A SINGLE-BORE HIGH-PRESSURE PNEUMATIC NEBULIZER OPERATINGWITH ALCOHOLS IN INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY

The behaviour of a single-bore high-pressure pneumatic nebulizer (SBHP PN) with alcohols in (ICP-AES) was investigated. A standard Meinhard n ebulizer was used for comparison. To this end, the drop size distribut ion of the primary aerosols, the analyte and solvent transport rates, W-tot and S-tot, the fraction of solvent transported in liquid and vap our forms, S-liq and S-vap, the excitation temperature of the plasma, T-exc, and the molecular emission intensity of the C-2 band were deter mined for solvents of different physical properties: The effect of the physical properties of the solvent on the nebulization process was al so studied. The results show that the SBHPPN gives rise, for all the s olvents studied, to primary aerosols that have smaller mean diameters than those produced by the Meinhard nebulizer for the same gas and liq uid flows. The relative decrease in volume median diameter (D-v,D-50) when switching from the Meinhard nebulizer to the SBHPPN is more notic eable for alcohols than for water. W-tot is significantly higher for t he SBHPPN than for the Meinhard nebulizer, particularly at high liquid flows. However, the differences between their S-tot values are less p ronounced. Under similar conditions, the SBHPPN gives rise, for all th e solvents studied, to higher emission intensities than the Meinhard n ebulizer. However, the relative signal enhancements achieved by changi ng from the SBHPPN to the Meinhard nebulizer are lower than the corres ponding analyte transport enhancements. The relative signal enhancemen ts achieved by switching from water to alcohols are lower for the SBHP PN than for the Meinhard nebulizer. This behaviour can be explained in terms of the higher S-tot values associated with the SBHPPN, which lo wer T-exc in comparison with the Meinhard nebulizer.