Infrared Spectroscopy in Process Analysis
Process Instrumental Methods
Published Online: 15 SEP 2006
Copyright © 2000 John Wiley & Sons, Ltd. All rights reserved.
Encyclopedia of Analytical Chemistry
How to Cite
Coates, J. P. and Shelley, P. H. 2006. Infrared Spectroscopy in Process Analysis. Encyclopedia of Analytical Chemistry. .
- Published Online: 15 SEP 2006
Infrared (IR) instruments have been in use as important measurement and analysis tools for process monitoring and production control for more than half a century. They range in complexity from the simplest filter-based photometers to opto-mechanically complicated devices, such as Fourier transform infrared (FTIR) instruments. Simple nondispersive infrared (NDIR) instruments are in common use for systems where one to a few main analytes are involved. For more complex measurement situations it is necessary to record more spectral information, and often full-spectral analyzers are used. Of the main analytical instrument techniques, IR analysis is the most versatile, where all physical forms of a sample may be considered – gas, liquids, solids and mixed phase materials. A wide range of sample handling options exists, and many of these may be adapted to either near-line/at-line production control or on-line process monitoring applications. Instrumentation used within a manufacturing environment usually requires special packaging to protect the instrument from the environment, and to protect the operating environment from the instrument. This places special constraints on the way that an instrument is designed and the way that it performs. Often, it is necessary to utilize special technologies, normally not required for laboratory instruments, to meet the performance objectives. For most practical installations within a production environment it is a normal requirement for the final instrument to comply with local manufacturing and electrical safety codes. The range of applications of IR spectroscopy is extremely broad and the technique can play an important role in virtually all industries for manufacturing quality and production control, and for environmental monitoring.