Chlorine, industrial production

Commercial metal anodes for the chlorine industry came about after the late 1960s when a series of worldwide patents were awarded (6—8). These were based not on the use of the platinum-group metals (qv) themselves, but on coatings comprised of platinum-group metal oxides or a mixture of these oxides with valve metal oxides, such as titanium oxide (see Platinum-GROUP metals, compounds Titanium compounds). In the case of chlor-alkaH production, the platinum-group metal oxides that proved most appropriate for use as coatings on anodes were those of mthenium and iridium. 

Large-Scale Industrial Production. Large amounts of chlorine dioxide ate used in pulp bleaching and smaller quantities ate used for the manufacture of sodium chlorite. In these appHcations, sodium chlorate is the only commercially available taw material. Chlorine dioxide production from sodium chlorate is achieved by the reduction of the chlorate ion in the presence of strong acid. The reaction consumes acid, so that acid and reducing agents must be constantly added to maintain the reaction. 

Industrial production of CI2 and chlorine chemicals is on a vast scale and comprises a major section of the heavy chemical industry. - Some aspects have already been discussed on p. 793, and further details are in the Panel. 

World production of Bra in 1990 was about 438 000 tonnes pa, i.e. about one-hundredth of the scale of the chlorine industry. The main producing countries are (tonnes) USA 177000, Israel 135 000, Russia 60000, UK 28 000, France 18 000 and Japan 15 000. The production capacity of Israel has recently increased almost threefold because of expanded facilities on the Dead Sea. Historically, bromine was shipped in individual 3-kg (net) bottles to minimize damage due to breakage, but during the 1960s bulk transport in monel metal drums (100-kg capacity) or lead-lined tanks (24 or 48 tonnes) was developed and these are now used for transport by road, rail and ship. The price of Bra in tank-car lots was 975/kg in 1990. 

Plants producing and handling halogens and halogen compounds Tantalum finds extensive use in the production and handling of hydrochloric and hydrobromic acid, chlorine and bromine and many of their derivatives. Absorbers, coolers and heaters which show considerable advantages in terms of heat-flux capabilities and corrosion resistance have been used on hydrochloric acid duties for over 40 years and condensers have been used in bromine plants for at least the same period. Typical applications of tantalum in the bromine and chlorine industries are listed in Table 5.27 . 

K.18 The industrial production of sodium metal and chlorine gas makes use of the Downs process, in which molten sodium chloride is electrolyzed (Chapter 12). Write a balanced equation for the production of the two elements from molten sodium chloride. Which element is produced by oxidation and which by reduction ... 

Industrial workers involved in chlorinated aromatic production including chlorophenol suffered dioxin-induced chloracne 2,3). Chloracne and other serious health disturbances have been attributed to polychloro-dibenzo-p-dioxins in workers involved in manufacturing 2,4,5-T 4, 5). Dioxins are toxic to chick embryos, guinea pigs, rabbits, and monkeys 6, 7, 8, 9, 10). 

This structure looks nothing like the structures of chlorine-containing compounds used in industrial processes. In fact, no dioxin is deliberately manufactured anywhere in the diverse chlorine industry. Nevertheless, dioxins are of concern for two reasons First, dioxins appear to be inevitable trace by-products of some reactions involving chlorine, particularly combustion and second, dioxins accumulate in the biosphere, where they have highly deleterious effects. 

Anodic chlorine evolution by electrolysis of concentrated chloride solutions is used for the large-scale industrial production of chlorine. The cathodic reaction, which is the ionization of molecular chlorine, is used in certain types of batteries. 

Mixtures of aqueous sodium hypochlorite (presumably the 15% available chlorine commercial product) and ethylene glycol were observed to erupt violently after an induction period of 4 to 8 minutes. Caution is advised in view of the use of glycol as a cooling fluid in industrial reactors. 

This book examines comprehensively the chlorine industry and its effects on the environment. It covers not only the history of chlorine production, but also looks at its products, their effects on the global environment and the international legislation which controls their use, release and disposal. Individual chapters are dedicated to subjects such as end use processes, water disinfection and metallurgy, environmental release of organic chlorine compounds, polychlorinated biphenyls, legal instruments and the future of the chlorine industry. 

The chlorine industry really took off at the end of the 1890s with the installation of the first mercury cell units. Since then the industry has coped with many problems, the main one being the fixed amount of caustic soda per ton of chlorine out of the cells. There have always been imbalances on the demand for chlorine and the demand for caustic soda. The two products quite often go their own way and no reason is seen to change this situation. 

While the industry has to balance out globally there are none the less regional imbalances. Asia still has a deficit of chlorine derivative production and a large demand for PVC. Much of this is met with imported EDC as the feedstock. The EDC in normal times comes mainly from low-energy-cost regions such as the Middle East... 

Charbroiled Chemicals has one facility adjacent to an industrial park on the outskirts of the city. The facility manufactures a range of products in 200 to 1000 gal batch reactors by chlorinating various organic feed materials. The reaction products go through several purification stages, with the chlorinated organic products sealed and labeled in 55 gal drums for delivery to customers. Byproducts that cannot be recycled are neutralized and stabilized in the waste treatment facility prior to disposal. 

The electrolysis of molten sodium chloride is an important industrial reaction. Figure 11.15 shows the large electrolytic cell used in the industrial production of sodium and chlorine. You will meet other industrial electrolytic processes later in this chapter. 

Describe the industrial production of chlorine, and its use in the purification of water. 

The industry responsible for the largest amount of WMPCs produced in 2001 was the alkalies and chlorine industry (SIC code 2812). (The Standard Industrial Classification [SIC] code is a system for categorizing all types of industries that operate in the United States.) The next four industries, in terms of WMPCs produced in 2001, were blast furnaces and steel mills (SIC code 3312), primary nonferrous metals (SIC code 3339), industrial inorganic chemicals (SIC code 2819), and storage batteries (SIC code 3691). Lead is an important by-product in all of these operations, accounting for the very large... 

Catalysis. The most important industrial use of a palladium catalyst is the Wacker process. The overall reaction, shown in equations 7—9, involves oxidation of ethylene to acetaldehyde by Pd(II) followed by Cu(II)-catalyzed reoxidation of the Pd(0) by oxygen (204). Regeneration of the catalyst can be carried out in situ or in a separate reactor after removing acetaldehyde. The acetaldehyde must be distilled to remove chlorinated by-products. 

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