Particle Beam Aqueous Sample Introduction for Hollow Cathode Atomic Emission Spectroscopy

The design and preliminary operating characteristics of a particle beam/hollow cathode atomic emission spectrometry (PB/HC-AES) device is described. By use of a high-efficiency thermal-concentric nebulization system coupled to a particle beam LC/MS interface, analyte particles originating in aqueous solution are introduced into a heated hollow cathode glow discharge for subsequent vaporization and excitation. Helium and argon are evaluated as discharge gases over a range of pressures and discharge currents, with He chosen as the most appropriate for subsequent analytical studies. Nebulization temperature, liquid (solvent) flow rate, and vaporization temperature are evaluated in order to determine their effects on analyte emission characteristics. Optimized sample introduction and He plasma operation conditions are employed to study the analytical characteristics of the PB/HC-AES system. Subsequent studies of cesium at ppm levels in diluted (1000 [times]) simulated nuclear waste solutions (5.0 M NaNO[sub 3] and 0.1 M KOH) indicated that the addition of excess chloride as a counterion, rather than nitrate, greatly enhances detectability. 26 refs., 7 figs.