Arc and Spark Systems

Commercial DC arc emission spectrometers and commercial spark spectrometers are available as stand-alone laboratory instruments. This list is not comprehensive, but examples include a DC arc ClD-based EcheUe system from Thermo Elemental (www.thermoelemen-tal.com), a multiple polychromator spark system with PMT detectors from Spectro Analytical Instruments (www.spectro-ai.com), and a spark spectrometer polychromator system with PMT detectors from Jobin Yvon, Inc. (www.jyhoriba.com). Many instrument companies make portable spark instruments, some small enough to be handheld, for use in sorting metal alloys at scrap yards, confirming the identity of alloys received at loading docks. 

Sequential and simultaneous ICP systems of many types are available from numerous instrument manufacturers. Most are available in radial or axial view, or both. Most spectrometers can be purged to reach 160 nm. Examples of some of the companies who make ICPs and DCPs are given. Jobin Yvon, Inc. makes a line of PMT-based high-resolution sequential systems, simultaneous systems, and combination sequential-simultaneous systems. PerkinElmer Inc. makes a scanning ICP with CCD detection, and a line of simultaneous CCD-based Echelle systems. Leeman Laboratories, Inc. makes an Echelle ICP spectrometer with an aperture grid available as a sequential system with rapid scanning PMT detection, a simultaneous system with a PMT array, and a combination system. Varian, Inc. makes a sequential ICP with PMT detection and a simultaneous system with CCD detection. ThermoElemental offers ICP Echelle spectrometers with CID detection and a sequential diffraction grating instmment with PMT detection. 

Spectrometer systems are now available with nitrogen purged, sealed optics for routine analysis from 120 to 800 nm. ICP systems that have this capability include instruments from Jobin Yvon, Inc. and from Spectro Analytical Instmments. There is one commercial DCP available from ThermoElemental, an Echelle spectrometer with CID detection. The ability to use lines in the vacuum UV permits the determination of the halogens and other elements whose most intense lines occur at 160 nm. 

Most systems, especially for use in industry, include an autosampler that allows unattended, overnight operation of the instrument. Computer software in commercial instruments controls the autosampler and the instrument, collects the data, performs the calculations, prints out the results, and shuts down the instrument when the analysis is completed. Most instruments have computer-controlled safety interlocks that shut down the plasma or the instrument and autosampler in the event a problem is detected. 

This list is not inclusive or comprehensive, but is meant to give the student a feeling for the types of instruments commercially available at the present time. Typical detection limits for elements determined by ICP emission spectrometry can be found in Appendix 

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