Evaluation of a Demountable Tangential Flow Torch for Microwave-Induced Plasma Atomic Emission Spectrometry

Abstract

A demountable torch for the microwave-induced plasma that utilizes a tangential flow pattern is described. This new torch is compared to a conventional all-quartz design in a series of comparative studies. Diagnostic studies consist of measurements of electron number densities, excitation temperatures, and ionization temperatures of an argon plasma generated in each torch. Hydrodynamic flow measurements, vertical emission profiles, and limits of detection provide further contrast between the characteristics of the demountable design and conventional all-quartz torch. The compatibility of the new torch design with supercritical CO, flows is demonstrated where the MIP is coupled with a packed-column supercritical fluid chromatograph for the purpose of element-specific detection. The physical advantages of the demountable torch over the all-quartz design are discussed.