Detection of Fine-particles in Suspension by Time-resolved Helium Microwave-induced Plasma Atomic Emission Spectrometry

Time-resolved helium microwave-induced plasma atomic emission spectrometry (He MIP AES) was developed for the detection of fine-particles in a suspension. The plasma was generated by 2.45 GHz microwave power (— 1 kW) with the Okamoto cavity of the surface wave mode at atmospheric pressure. Sample particles of Ag (median dia. 368, 518, 833, 1304 nm), Al2O3 (409 nm), BaTiO3 (2062 nm) and Fly-Ash (BCR-038, 5413 nm, composition: As, Cl, Co, Cr, Cu, F, Fe, Mn, Na, Pb, Zn etc.) were used. A suspension including one of these particles was nebulized, and the generated droplets included or adhered to the particle were introduced into the center of the annular He-MIP through an inner tube of a torch along with the carrier gas (Ar). A time-resolved atomic emission spectrometry was studied for particulate composition analysis of each droplet. Preliminary experimental data are presented. The time-resolved He-MIP AES could be detected with sufficient sensitivity.