Chemical apphcation

The term feedstock in this article refers not only to coal, but also to products and coproducts of coal conversion processes used to meet the raw material needs of the chemical industry. This definition distinguishes between use of coal-derived products for fuels and for chemicals, but this distinction is somewhat arbitrary because the products involved in fuel and chemical appHcations are often identical or related by simple transformations. For example, methanol has been widely promoted and used as a component of motor fuel, but it is also used heavily in the chemical industry. Frequendy, some or all of the chemical products of a coal conversion process are not isolated but used as process fuel. This practice is common in the many coke plants that are now burning coal tar and naphtha in the ovens. 

Filled Resins. Filled compositions meet the requkements of an increased variety of mechanical, electrical, and chemical appHcations. Physical properties of filled granular compounds are shown in Table 4 (81). 

Consumption of PTEE increases continuously as new appHcations are being developed. Electrical appHcations consume half of the PTEE produced mechanical and chemical appHcations share equally the other half Various grades of PTEE and their appHcations are shown in Table 7. 

A description of PTFE resins and their classification are given in ASTM D1457-83. A comprehensive listing of industrial and military specifications covering mechanical, electrical, and chemical appHcations of PTFE can be found in Reference 119. 

Tunable Lasers. TunabiHty is an important feature for many spectroscopic and chemical appHcations. The availabiHty of tunable lasers has been reviewed (48). 

By agreement between the purchaser and the suppHer, analyses may also be requited and limits estabUshed for elements or compounds not specified. This grade is intended for chemical appHcations requiting low silver and bismuth contents. 

Other chemical apphcations being studied include the use of microwaves in the petroleum (qv) industry (175), chemical synthesis (176,177), preparation of semiconductor materials (178), and the processing of polymers (179). 

At high speeds, the pond of the flooded nip size press becomes turbulent. RoU maintenance is a problem with the gate-roU size press. To avoid these problems, the blade/rod metering size press was developed. Short-dweU coater heads are used to apply a precisely controUed quantity of chemicals to the size press roUs. This quantity is controUed with either a metering blade or a metering rod. Blade or rod metering eliminates the pond, and does not increase the number of roUs required for surface chemical appHcation. 

Chemistry. The material and energy available in plasmas can be used to excite materials and drive chemical reactions. The unique characteristics of plasmas, especially thek abundance of energetic species, have been exploited in plasma chemical apphcations (79—84). 

Approximately 600,000 metric tons of aluminum hydroxides were used in chemical appHcations in the United States in 1988 40% as fillers, 45% for the production of aluminum chemicals, and 15% for various other uses. Carpet backing was the principal filler type appHcation foUowed by polyester products. 

Chemical appHcations of Mn ssbauer spectroscopy are broad (291—293) determination of electron configurations and assignment of oxidation states in stmctural chemistry polymer properties studies of surface chemistry, corrosion, and catalysis and metal-atom bonding in biochemical systems. There are also important appHcations to materials science and metallurgy (294,295) (see Surface and interface analysis). 

Consumptions of primary tin for chemical appHcations by the five reporting countries from 1975 to 1980 is shown in Table 12. The use of primary tin in chemical appHcations increased sharply in the United States and Germany, but declined in the United Kingdom and Italy. In 1979, ca 11% of the total U.S. demand for tin was accounted for by tin chemicals. In 1977, the tin consumption in tin chemicals production was based on ca 80% primary tin usage... 

In 1972, the concept of pattern recognition as a general problem solving tool for a broad scope of chemical appHcations was introduced (9,10). 

O. L. Davies and co-workers. The Design andAna/ysis of Industria/Experiments, 2nd ed., Hafner, New York, 1956 reprinted by Longman, New York, 1987. This book, which is a sequel to the authors basic text Statistica/Methods in Eesearch and Production, is directed at industrial situations and chemical appHcations. Three chapters are devoted to factorial experiments and one chapter to fractional factorial plans. A lengthy chapter (84 pp.) discusses the deterrnination of optimum conditions and response surface designs, which are associated with the name of G. Box, one of the seven co-authors. Theoretical material is presented in chapter appendices. 

E. Lindgren, R Geladi, A. Berglnnd, M. Sjostrom and S. Wold, Interactive variable selection (IVS) for PLS. Part II chemical apphcations, J. Chemom., 9, 331-342 (1995). 

Particularly in industries structured in small enterprises with limited nsers know-how and a wide range of chemicals apphcations, the field service of preparations manufactnrers or the trade have a central role in conveying product information and in advising on apphcations. In particular the chemicals business and the formulators could also expand their bnsiness areas to include information and consultation services (with the associated cnstomer retention). 

F. A. Cotton, Chemical Apphcations of Group Theory , 3rd edn., John Wiley Sons, New York, 1990. 

This book will focus on the chemical finishing of textiles, the application of relatively minor amounts of chemicals (often < 5 g m" ) to, in most cases, both sides of the fabric. Subsequent chapters will discuss the importance of each specific finish, the chemical mechanism for the effect, the chemicals used to provide the desired properties, the apphcation and fixation procedures, the relevant evaluation methods and trouble shooting tips. Processes that employ high levels of chemical apphcation (15-50 g m and more), primarily as one-sided treatments, such as coating are addressed only briefly in Chapter 2. 

Novel organic syntheses that are possible in usual acidic media can be accomplished in superacids, including syntheses of economically important hydrocarbons. The remarkable ability of superacids to bring about hydrocarbon transformations can open up new fields in chemistry. In consideration of the exceptionally high activity of Hquid superacids, research was extended to prepare solid superacids. As for chemical appHcations of liquid superacids, efforts were made to attach them to soHd materials, and the results are found in extensive patent literature [10-13]. 

The chief examples are smelting for the recovery of metals from ores, cement manufacture, and lime burning. The converters, roasters, and khns for these purposes are huge special devices, not usuahy adaptable to other chemical apphcations. Shale oil is recovered from crushed rock in a vertical khn on a batch or continuous basis-moving bed in the latter case-sometimes in a hydrogen-rich atmosphere for simultaneous derutiifrcation and desulfurization. The capacity of ore roasters is of the order of 300-700 tons/(day)(m of reactor volmne). Rotary kilns for cement have capacities of (1.4-1.1 tons/(day)(m ) for other purposes the range is 0.1-2. 

T. N. Truong, W. T. Duncan, and R. L. Bell, in Chemical Apphcations of Density Eunc-tional Theory, B. B. Laird, R. B. Ross, and T. Ziegler, Eds., American Chemical Society, Washington, DC, 1996. 

The optical spectra of radicals provide important data for testing open-shell methods. Until about 1960 open-shell MO studies were rather rare. An intensive development of open-shell MO theory started in the early sixties and was followed by chemical apphcations and systematic studies in the late sixties. At present it is possible to state that the physicochemical properties of radicals are predicted with an accuracy comparable to that attained for closed-shell molecules. This is important not only from the viewpoint of the electronic spectra, which can hardly be interpreted without MO theory, but also from the viewpoint of the general theory of reactivity, since radicals and excited states offer the means to overcome spin and S5unmetry restrictions in certain chemical reactions. 

A number of excellent books have been pubHshed and these should be consulted when more extensive treatments of the theory of Mossbauer spectroscopy are required. (1) Mossbauer Spectroscopy, by N.N. Greenwood and T.C. Gibb, Chapman and Hall, 1971 (2) Chemical Apphcations of Mossbauer Spectroscopy , V.l. Goldanskii and R.H. Herber (eds). Academic Press, 1968 and (3) NMR, NQR, EPR and Mossbauer Spectroscopy in Inorganic Chemistry by R. V. Parrish, Ellis Norwood, 1990. 

Acronyms XPS or XPES X-ray photoelectron spectroscopy, ESCA electron spectroscopy for chemical apphcations (originally analysis), PESIS photoelectron spectroscopy of inner shell, ARXPS angle resolved X-ray photoelectron spectroscopy. 

ESGA Electron Spectroscopy for Chemical AppHcations (originally Analysis), 50 ESD Electron Stimulated Desorption, 12... 

A number of software tools for HAZOPS have been developed (eg Dyadem ) hut these are targeted at chemical appHcations and are not available on an open source basis. 

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