Infrared pollutant control

Hanst PL, Spiller LL, Watts DM, et al. 1975. Infrared measurements of fluorocarbons, carbon tetrachloride, carbonyl sulfide, and other atmospheric trace gases. J Air Pollut Control Assoc 25 1220-1226. 

Hanst, P. L., L. L. Spiller, D. M. Watts, J. W. Spence, and M. F. Miller (1975). Infrared measurement of fluorocarbons, carbontetrachloride, carbonylsulfide and other atmospheric trace gases. J. Air Pollut. Control Assoc. 25, 1220-1226. 

Environmental scientists can monitor the pollutant gases in the air using an instrumental technique called infrared spectroscopy (see Chapter 18, page 241). It works quickly and accurately to monitor pollutants, including nitrogen dioxide, sulfur dioxide, carbon monoxide and carbon dioxide, as well as more than a hundred VOCs and low-level ozone. The scientists can use the characteristic wavelengths of infrared radiation absorbed by the molecules of the pollutants to identify them. They can also analyse the intensity of the absorptions to find the concentration of each pollutant present in a sample. Monitored over a period of time, the scientists provide useful information on the effectiveness of pollution control measures introduced locally and on a global level. 

The unique appearance of an infrared spectrum has resulted in the extensive use of infrared spectrometry to characterize such materials as natural products, polymers, detergents, lubricants, fats and resins. It is of particular value to the petroleum and polymer industries, to drug manufacturers and to producers of organic chemicals. Quantitative applications include the quality control of additives in fuel and lubricant blends and to assess the extent of chemical changes in various products due to ageing and use. Non-dispersive infrared analysers are used to monitor gas streams in industrial processes and atmospheric pollution. The instruments are generally portable and robust, consisting only of a radiation source, reference and sample cells and a detector filled with the gas which is to be monitored. 

Parker H D and Cormack D (1984) Evaluation of Infrared Line Scan (IRLS) and Side Looking Airborne Radar (SLAR) over controlled oil spills in the North Sea, in Remote Sensing for Control of Marine Pollution, Jean-Marie Massin ed., NATO-Challenges of Modem Society Vol. 6, pp 237-256 REMPEC For the Regional Marine Pollution Emergency Response Centre for the Mediterranean Sea (REMPEC) see http //www.rempec.org... 

Atmospheric N20 was discovered in 1938 by Adel via infrared absorption features in the solar spectrum. For the next 30 yr, N20 aroused little interest, presumably because it is neither a hazardous pollutant nor does it display any particular chemical activity. In fact, there are no gas-phase reactions that remove it from the troposphere as far as we know. In the stratosphere (see Chapter 3), N20 undergoes photodecomposition, and it reacts with O( D). The second reaction is the major source of higher nitrogen oxides in that region, and since these reduce ozone catalytically via chain reactions, N20 is an important agent in controlling the stratospheric ozone balance. The recognition of this relationship by Crutzen (1970, 1971) and McElroy... 

Parker (1971) has discussed various aspects of infrared spectroscopy which are of use in studies of water pollution and in the analysis of water. Rosen (1967) has also discussed water pollution and its control. He has mentioned the problems involved in obtaining samples of polluted water on a routine basis. Mattson et al. (1970) have used the ATR technique to identify crude oils and tars contaminating the waters of the Santa Barbara Channel. 

Infrared spectroscopy has proved to be a very effective tool for the investigation of solid pollutants. For example, contaminants, such as pesticides, organic and inorganic sprays, or dusts on plants, may be examined by using this technique. GC-IR spectroscopy has been used to investigate the degradation products of Mirex (dodecachloropentacyclodecane), a pesticide used in the control of fire ants [36], One of the requirements for pesticides is that they rapidly decompose in the environment, and GC-IR spectroscopy can be used to identify Mirex derivatives. This technique has an advantage over GC-MS, for instance. 

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