Process analysis spectrometry

The environmental appHcations of infrared spectrometry are many and varied. Many appHcations at industrial sites are analogous to those for on-line process analysis waste streams and recycling processes can be monitored in the same way. Commercial infrared stack-gas monitors are based on either an extractive probe attached to a long-path gas ceU or an open-path (across stack) configuration (69). Stack plume and flare monitoring can be done externally... 

Multiway and particularly three-way analysis of data has become an important subject in chemometrics. This is the result of the development of hyphenated detection methods (such as in combined chromatography-spectrometry) and yields three-way data structures the ways of which are defined by samples, retention times and wavelengths. In multivariate process analysis, three-way data are obtained from various batches, quality measures and times of observation [55]. In image analysis, the three modes are formed by the horizontal and vertical coordinates of the pixels within a frame and the successive frames that have been recorded. In this rapidly developing field one already finds an extensive body of literature and only a brief outline can be given here. For a more comprehensive reading and a discussion of practical applications we refer to the reviews by Geladi [56], Smilde [57] and Henrion [58]. 

In polymer/additive deformulation (of extracts, solutions and in-polymer), spectroscopic methods (nowadays mainly UV, IR and to a lesser extent NMR followed at a large distance by Raman) play an important role, and even more so in process analysis, where the time-consuming chromatographic techniques are less favoured. Some methods, as NMR and Raman spectrometry, were once relatively insensitive, but seem poised to become better performing. Quantitative polymer/additive analysis may benefit from more extensive use of 600-800 MHz 1-NMR equipped with a high-temperature accessory (soluble additives only). 

T. B. Colin, Mass spectrometry in chemical process analysis, in Spectroscopy in Process Analysis, J.M. Chalmers (ed.), Sheffield Academic Press, Sheffield, UK, 2000. 

Dorfner, R., Ferge, T, Yeretzian, C., Kettrup, A., Zimmermann, R. (2004) Laser mass spectrometry as on-line sensor for indiKtrial process analysis Process control of coffee roasting. Anal. Chem. 76 1386-1402. 

Mass Spectrometers as Process Analyzers. The use of mass spectrometers in process analysis lias not been widespread because nl its perceived complexity and high cost. Technological advancements over the past decade or two have reduced costs and simplified mass spectrometry to the point where it is suitable lor a number of process analytical applications in place of infrared absorption or gas chromatography mass spectrometer is well accepted in such applications hecause of low cosi. good reliability, and ease of cnmpuicr-controllcd interfaces. 

One indication of the developing interest in PATs in the pharmaceutical area is the number of book chapters and review articles in this field that have appeared in the last few years. Several chapters in The Handbook of Vibrational Spectroscopy3 are related to the use of various optical spectroscopies in pharmaceutical development and manufacturing. Warman and Hammond also cover spectroscopic techniques extensively in their chapter titled Process Analysis in the Pharmaceutical Industry in the text Pharmaceutical Analysis.4 Pharmaceutical applications are included in an exhaustive review of near-infrared (NIR) and mid-infrared (mid-IR) by Workman,5 as well as the periodic applications reviews of Process Analytical Chemistry and Pharmaceutical Science in the journal Analytical Chemistry. The Encyclopedia of Pharmaceutical Technology has several chapters on spectroscopic methods of analysis, with the chapters on Diffuse Reflectance and Near-Infrared Spectrometry particularly highlighting on-line applications. There are an ever-expanding number of recent reviews on pharmaceutical applications, and a few examples are cited for Raman,7 8 NIR,9-11 and mid-IR.12... 

Sandmeier EP, Keller J, Heinzle E, Dunn IJ, Bourne JR (1988) Development of an on-line pyrolysis mass spectrometry system for the on-line analysis of fermentations. In Hienzle E, Reuss M (eds). Mass Spectrometry in Biotechnological Process Analysis and Control. Plenum, New York, p 209... 

Kotiaho, T. On-site environmental and in situ process analysis by mass spectrometry. J. Mass Spectrom. 31, 1-15 (1996)... 

Baumbach, J.I. Process analysis using ion mobility spectrometry. Anal. Bioanal. Chem. 384, 1059-1070 (2006)... 

Due to the absorption bands in NIR being weaker than in UV-Vis absorption, NIR spectrometry is not as useful for quantitative measurements but offers better qualitative analysis because of improved selectivity. NIR techniques can handle both liquid and solid samples. Near infrared reflectance analysis (NIRA) has found wide application in process analysis, especially for highly absorbing compounds such as foodstuffs Coal, grain, pulp and paper products and some pharmaceuticals can also be determined by NIRA ". The reflectance from the sample is reported relative to reflectance from a standard reference surface. 

Infrared spectrometry is currently exploited in process analysis but less so than near IR and Raman spectrometry. The reasons for this are the strong absorbances of most mid IR bands and the sensitivity of mid IR optical materials to chemical erosion. There is also a relative lack of practical hbre optic options for use in the mid IR range since silver halide and chalcogenide glasses, which cover the whole of the mid IR region, can attenuate the radiation by as much as 95%, even over short distances. Other hbres such as zirconium fluoride cut off below 2500 cm and so the fingerprint region information is lost. 

The trade-off between the simplicity of atmosphere pressure work, spectral resolution, method selectivity and sensitivity strongly favours it for process analysis compared with even the modest vacuum pumping requirements of MMW spectrometry at the usual pressures of tens of Pa. Where the balance occurs will... 

The positive attributes of MMW spectrometry for gas phase analysis include its high selectivity when operated at low pressure. The working pressure can be readily achieved with a modest rotary and turbomolecular pump combination for laboratory and process analysis applications. The pumping requirements will also form an integral part of the essential process of sample acquisition and evacuation. 

Process mass spectrometry (MS) is a very powerful technique for process monitoring and control, providing a unique combination of speed, selectivity, dynamic range, accuracy, precision and flexibility. The technique has become a standard for gas-phase analysis in several industrial applications, including steel manufacturing, fermentation off-gas analysis, and the production of ethylene oxide and ammonia. Among its attributes ... 

Process MS is a reliable technique that can provide rapid and precise multicomponent analysis on process streams. The ability to monitor multiple sample points with a single analyzer makes MS very economical for many applications, even with the high cost of the analyzer itself Maintenance requirements on modern MS analyzers are on a par with or lower than most other analyzer technologies. In addition to permanent installations for routine process control, these attributes also make process mass spectrometry extremely useful for process development and troubleshooting. 

See alsa Fuels Gaseous Oil-Based. Gas Chromatography Mass Spectrometry. Process Analysis Chromatography. 

See also Air Analysis Outdoor Air. Mass Spectrometry Electron Impact and Chemical Ionization Mass Separation Environmental Applications. Process Analysis Overview. Thermal Analysis Temperature-Modulated Techniques. 

See also Activation Analysis Neutron Activation. Atomic Absorption Spectrometry Principles and Instrumentation. Atomic Emission Spectrometry Principles and Instrumentation. Chromatography Overview Principles. Gas Chromatography Pyrolysis Mass Spectrometry. Headspace Analysis Static Purge and Trap. Infrared Spectroscopy Near-Infrared Industrial Applications. Liquid Chromatography Normal Phase Reversed Phase Size-Exclusion. Microscopy Techniques Scanning Electron Microscopy. Polymers Natural Rubber Synthetic. Process Analysis Chromatography. Sample Dissolution for Elemental Analysis Dry... 

Ultraviolet (UV)-visible spectrometry, near-infrared spectrometry, mid-infrared spectrometry, and Raman spectrometry have all been used for online process analysis (including inline and noninvasive applications). 

See also Electrophoresis Two-Dimensional Gels Nucleic Acids. Enzymes Enzyme-Based Assays. Flow Injection Analysis Principles. Fluorescence Quantitative Analysis. Lab-on-a-Chip Technologies. Mass Spectrometry Matrix-Assisted Laser Desorption/loniza-tion Time-of-Flight. Microelectrodes. Microscopy Overview. pH. Process Analysis Overview Chromatography Electroanalytical Techniques Sensors Acoustic Emission Maintenance, Reliability, and Training. Proteins Overview. Proteomics. Purines, Pyrimidines, and Nucleotides. Sensors Oven/iew. Spectrophotometry Overview. 

Near-infrared spectrometry This is an alternative for the process analysis of bulk sweeteners, e.g., raw... 

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