Industrial Manufacture and Uses

The earliest methods for the manufacture of phosgene were based upon John Davy s original procedure of exposing a mixture of carbon monoxide and dichlorine to sunlight [577]. Later methods (used to a limited extent in Italy and France during World War I) involved the oxidation of tetrachloromethane or hexachloroethane with suIfur(VI) oxide or fuming sulfuric acid (see Chapter 5) [577,1778]. Alternative methods proposed for the manufacture of phosgene, but which have not been commercialized, are described in Chapter 5. 

The modern industrial preparation of phosgene has not changed significantly since the 1920s. It is based on the reaction  

The process comprises the preparation and purification of the raw materials, carbon monoxide and dichlorine, the metering and mixing of these materials, the reaction of the 

The process is normally operated on a continuous basis, employing a high degree of automation. Owing to the toxicity of phosgene, extensive safety features are an integral part of the plant design. 

Carbon dioxide is removed from CO streams by amine (e.g. ethanolamine) scrubbing, and high concentration CO for COCl manufacture can be obtained from absorption of CO-containing streams into ammoniacal copper(I) solutions under pressure. The CO is 

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Methylenediphenyl diisocyanate can be released to the environment in waste stream emissions from sites of industrial manufacture and use. Toxic Release Inventory reports to the United States Environmental Protection Agency before at least the mid-1990s were subject to serious overestimation of the releases to the environment, because of errors in the way that the figures were calculated by industry. Within the European Union, total emissions from production sites in 1996 were about 43 kg and emissions from processing plants in the same year were about 7100 kg (European Union, 1999). 

A. Bokranz and H. Plum, Industrial Manufacture and Use of Organotin Compounds, Schering AG, Bergkamen, 1975. 

The growing security threat of COCs thus presents a new challenge to working with chemicals in the laboratory, especially in small-scale industrial and academic settings. While large-scale industrial manufacturing and use of COCs is a dominant concern in national and international chemical security, use of chemicals at the laboratory scale poses a unique and significant security threat and is the main focus of this report. 

Although a few simple hydrides were known before the twentieth century, the field of hydride chemistry did not become active until around the time of World War II. Commerce in hydrides began in 1937 when Metal Hydrides Inc. used calcium hydride [7789-78-8J, CaH2, to produce transition-metal powders. After World War II, lithium aluminum hydride [16853-85-3] LiAlH, and sodium borohydride [16940-66-2] NaBH, gained rapid acceptance in organic synthesis. Commercial appHcations of hydrides have continued to grow, such that hydrides have become important industrial chemicals manufactured and used on a large scale. 

Clean Air Act and its amendments ia 1970, 1977, and 1990 1967 Air Quahty Standards and National Air Pollution Acts and 1970 National Environmental PoHcy Act) (2) better waste disposal practices (1965 SoHd Waste Disposal Act 1976 Resource Conservation and Recovery Act) (see Wastes, industrial Waste treatment, hazardous wastes) (i) reduced noise levels (1972 Noise Control Act) (4) improved control of the manufacture and use of toxic materials (1976 Toxic Substances Control Act) and (5) assignment of responsibiUty to manufacturers for product safety (1972 Consumer Product Safety Act) (15,16). 

Occurrence. Carbon monoxide is a product of incomplete combustion and is not likely to result where a flame bums in an abundant air supply, yet may result when a flame touches a cooler surface than the ignition temperature of the gas. Gas or coal heaters in the home and gas space heaters in industry have been frequent sources of carbon monoxide poisoning when not provided with effective vents. Gas heaters, though properly adjusted when installed, may become hazardous sources of carbon monoxide if maintained improperly. Automobile exhaust gas is perhaps the most familiar source of carbon monoxide exposure. The manufacture and use of synthesis gas, calcium carbide manufacture, distillation of coal or wood, combustion operations, heat treatment of metals, fire fighting, mining, and cigarette smoking represent additional sources of carbon monoxide exposure (105—107). 

A. J. Rudge, The Manufacture and Use ofEhurine and its Compounds., Oxford University Press (for Imperial Chemical Industries Ltd.), Cambridge, Mass., 1962, p. 71. 

The manufacture and uses of oxiranes are reviewed in (B-80MI50500, B-80MI50501). The industrially most important oxiranes are oxirane itself (ethylene oxide), which is made by catalyzed air-oxidation of ethylene (cf. Section 5.05.4.2.2(f)), and methyloxirane (propylene oxide), which is made by /3-elimination of hydrogen chloride from propene-derived 1-chloro-2-propanol (cf. Section 5.05.4.2.1) and by epoxidation of propene with 1-phenylethyl hydroperoxide cf. Section 5.05.4.2.2(f)) (79MI50501). 

Batch process A treatment process in which a tank or reactor is filled, the wastewater (or solution) is treated or a chemical solution is prepared and the tank is emptied. The tank may then be filled and the process repeated. Batch processes are also used to cleanse, stabilize or condition chemical solutions for use in industrial manufacturing and treatment processes. 

A scientific, non-profit making, non-commercial association, financed by 50 of the leading companies with interests in the manufacture and use of chemicals. It provides a scientific fomm through which the European chemical industry can research, review, assess and publish studies on the ecotoxicoiogy and toxicology of chemicals. 

An industrial association ofproducers and users of acrylonitrile, concerned with the health, safety, environmental and other matters regarding the manufacture and use of the substance. 

For decades the problem of stability has plagued colloid chemists and others engaged in the manufacture and use of dispersions. Only a determined practical approach to the solution of this problem has been responsible for the modest accumulation of theoretical knowledge in existence today. In the field of dispersions, for example, problems of physical instability have been solved for paints, pharmaceuticals, adhesives, asphalt, detergents, and commodities used in the graphic arts, in addition to the numerous successful encounters with instability (or sometimes with undesired stability) in the food industry. 

Nuttall, C., Chocolate marketing and other aspects of the confectionery industry worldwide, in Industrial Chocolate Manufacture and Use, Beckett, S. T., Ed., Van Nostrand Reinhold, New York 1988, chap. 18. 

Acrylonitrile is readily volatile, and significant quantities escape into air during manufacture and use. Volatilization may also occur from hazardous waste sites. In air, acrylonitrile is degraded primarily by reaction with hydroxyl radicals, with an estimated half-life of 5 to 50 hours. Acrylonitrile has been detected in air in the vicinity of various industrial sources at concentrations from 0.1 to 325 ppb, but has not been detected in typical ambient air. 

Clow, A. and Clow, N. L., The Chemical Revolution, The Batehworth Press, London, 1952, 140. Imperial Chemical Industries, Sulphuric Acid Manufacture and Use, Kynoch Press, Birmingham, England, 1955, 16. 

Recent data reported to the TRI indicate that environmental releases of hexachloroethane from manufacture and industrial processing total about 51,088 pounds (TRI93 1995). However, these data do not include releases from the manufacture and use of military smoke and pyrotechnic devices, since federal facilities are not required to report releases to the TRI. 

Edwards and Instone(5), have reviewed the manufacture and use of the particulate products which, as they describe it, are made by the fast moving consumer goods industry and used by consumers around the world. It is claimed that all the products of this sector have the following common features ... 

Exposure Levels in Environmental Media. All humans are exposed to at least low levels of chloroform via inhalation of contaminated air, and most humans are exposed by drinking contaminated water. Estimates from intake via inhalation and ingestion of drinking water, based on limited data, are available (see Section 5.5). Exposure from foods cannot be estimated, due to the lack of data. Current information on exposure to chloroform from water, air, and foods, especially for workers or people who live near manufacturing and use facilities, water and waste water-treatment plants, municipal and industrial... 

Production, Use, Release, and Disposal. Production methods for 1,2-diphenylhydrazine are well described in the literature (including he patent literature) there does not appear to be a need for further information in this area. Uses of 1,2-diphenylhydrazine are documented but no recent production figures or detailed descriptions of uses are available. This information is useful for estimating the potential for environmental releases from manufacturing and use industries as well as the potential environmental burden, but it is difficult to obtain in the detail desired since it is considered confidential business information for those industries that manufacture... 

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