Copper industrial processes

Eurther progress was made in the eighteenth and early nineteenth centuries. Many metals were discovered upon the development of experimental chemistry. The modem metallurgical industry was bom with the invention of steelmaking in 1856 (see Steel). Industrial processes for making zinc (see Zinc and zinc alloys), aluminum (see Aluminumand aluminum alloys), and copper followed before the end of the nineteenth century. These processes made possible the industrial revolution and the development of an industrial society relying heavily on the use of metals. 

Japan, Canada, and the United States accounted for 70% of the 1995 estimated world production of 2000 t (Table 5). At least 100 t of selenium was also available to Western markets from the former Soviet bloc. Selenium production is expected to rise in South America, particularly Chile, as the copper industry continues rapid expansion. A considerable amount of unrefined selenium is also shipped to Chile and the Philippines for conversion to final commercial product by either hydrometaHurgical or distillation processes. 

Also, corrosion may result in contamination at some downstream point in the steam-water cycle. For example, iron and copper ions often may be present as corrosion products in steam and condensate and consequently will reduce the purity of the steam. This may render the steam unsuitable for certain industrial processes or applications where live steam injection is required. 

The foregoing has been a brief and general account of the environmental impact that ensues from the processing of sulfidic resources of metals. For obvious reasons, a major emphasis has been placed with regard to the copper industry in the presentations. It will be worthwhile for the reader to become more acquainted with this area, which has featured in as many as twenty papers contained in the proceedings of the EPD-96 Congress (see Literature). 

Primary copper processing results in air emissions, process wastes, and other solid-phase wastes. Particulate matter and sulfur dioxide are the principal air contaminants emitted by primary copper smelters. Copper and iron oxides are the primary constituents of the particulate matter, but other oxides, such as arsenic, antimony, cadmium, lead, mercury, and zinc, may also be present, with metallic sulfates and sulfuric acid mist. Single-stage electrostatic precipitators are widely used in the primary copper industry to control these particulate emissions. Sulfur oxides contained in the off-gases are collected, filtered, and made into sulfuric acid. 

The oxidative dehydrogenation of ethanolamine over skeletal copper catalysts at temperatures, pressures and catalyst concentrations that are used in industrial processes has been shown to be independent of the agitation rate and catalyst particle size over a range of conditions. A small content of chromia (ca. 0.7 wt %) provided some improvement to catalyst activity and whereas larger amounts provided stability at the expense of activity. 

Sirosmelt [CSIRO smelting] A copper smelting process developed by the Commonwealth Scientific Industrial Research Organization (CSIRO), Australia. Used in Miami, AZ. See Isasmelt. 

Chapter 2 to 6 have introduced a variety of reactions such as asymmetric C-C bond formations (Chapters 2, 3, and 5), asymmetric oxidation reactions (Chapter 4), and asymmetric reduction reactions (Chapter 6). Such asymmetric reactions have been applied in several industrial processes, such as the asymmetric synthesis of l-DOPA, a drug for the treatment of Parkinson s disease, via Rh(DIPAMP)-catalyzed hydrogenation (Monsanto) the asymmetric synthesis of the cyclopropane component of cilastatin using a copper complex-catalyzed asymmetric cyclopropanation reaction (Sumitomo) and the industrial synthesis of menthol and citronellal through asymmetric isomerization of enamines and asymmetric hydrogenation reactions (Takasago). Now, the side chain of taxol can also be synthesized by several asymmetric approaches. 

More than 60 years after its simultaneous discovery by Rochow and Muller, the direct reaction of copper-activated silicon with alkyl chlorides is arguably still the most important industrial process for the preparation of basic organosilanes. An inspiring historic account highlighting the significance of this seminal work has been given by Seyferth.12 A comprehensive review on the subject has been written by Jung and Yoo.13 The most recent work associated with the direct process is concerned with the role of metallic promoters, such as Zn and Cd, as well as mechanistic aspects.14... 

Since hydrogen burns cleanly and reacts completely with oxygen to produce water vapor, this makes it more desirable than fossil fuels for essentially all industrial processes. For example, the direct reduction of iron or copper ores could be done with hydrogen rather than smelting by coal or oil in a blast furnace. Hydrogen can be used with conventional vented burners as well as unvented burners. This would allow utilization of almost all of the 30 to 40% of the combustion energy of conventional burners that is lost as vented heat and combustion by-products. 

The oxidative carbonylation of alcohols and phenols to carbonates can be catalyzed by palladium or copper species [154-213]. This reaction is of particular practical importance, since it can be developed into an industrial process for the phosgene-free synthesis of dimethyl carbonate (DMC) and diphenyl carbonate (DPC), which are important industrial intermediates for the production of polycarbonates. Moreover, DMC can be used as an eco-friendly methylation and carbonylation agent [214,215]. The industrial production of DMC by oxidative carbonylation of methanol has been achieved by Enichem [216] and Ube [217]. 

Since the oxidative polymerization of phenols is the industrial process used to produce poly(phenyleneoxide)s (Scheme 4), the application of polymer catalysts may well be of interest. Furthermore, enzymic, oxidative polymerization of phenols is an important pathway in biosynthesis. For example, black pigment of animal kingdom "melanin" is the polymeric product of 2,6-dihydroxyindole which is the oxidative product of tyrosine, catalyzed by copper enzyme "tyrosinase". In plants "lignin" is the natural polymer of phenols, such as coniferyl alcohol 2 and sinapyl alcohol 3. Tyrosinase contains four Cu ions in cataly-tically active site which are considered to act cooperatively. These Cu ions are presumed to be surrounded by the non-polar apoprotein, and their reactivities in substitution and redox reactions are controlled by the environmental protein. 

Redox reactions are involved in some very important industrial processes, such as iron and steel production. However, the widespread use of metals has occupied a relatively small part of human history. In the Stone Age, humans relied on stone, wood, and bone to make tools and weapons. The Stone Age ended in many parts of the world with the start of the Bronze Age, which was marked by the use of copper and then bronze (an alloy of copper and tin). In the Iron Age, bronze was replaced by the use of iron. The dates of the Bronze Age and the Iron Age vary for different parts of the world. 

The reaction has been developed into an industrial process which has been in production for about 40 years now. Although eq. 8.4 does not tell about it, the process suffers from the need of a highly corrosive reaction mixture containing large amounts of copper chlorides - a rather nasty situation from environmental aspects. 

In most industrial processes, copper is produced from the ore chalcopyrite, a mixed copper-iron sulfide mineral, or from the carbonate ores azurite and malachite. The extraction process depends on the chemical compositions of the ore. The ore is crushed and copper is separated by flotation. It then is roasted at high temperatures to remove volatile impurities. In air, chalcopyrite is oxidized to iron(ll) oxide and copper(ll) oxide ... 

In another industrial process, flue dusts from smelting lead and zinc concentrates are boiled in acidified water. Thallium dissolves and is separated from insoluble residues by filtration. Dissolved thallium in solution then is precipitated with zinc. Thallium is extracted from the precipitate by treatment with dilute sulfuric acid which dissolves the metal. The solution may also contain zinc, cadmium, lead, copper, indium, and other impurities in trace amounts. These metals are precipitated with hydrogen sulfide. The pure thallium sulfate solution then is electrolyzed to yield thallium. 

Continnons casting is used in the steel and copper industries. In this process, molten metal is delivered to a permanent mold in much the same way as semicontinuous... 

Mono-olefins (un) react with solid copper(I) halides to form unstable complexes of the type [CuX(un)] (X = Cl, Br), which dissociate into their constituents above 0° (67, 138). Dienes (e.g., butadiene, isoprene, pipery-lene, bicyclo[2,2,l]hepta-2,5-diene, and cyclopolyolefins) form more stable complexes of the type [Cu2X2(diene)J (1,63, 67,138,192), in which a copper atom is attached to each C C bond industrial processes to separate dienes from mono-olefins and paraffins are based on this difference in stability (8). Complexes of the type [Cu(un)]+, [CuCl(un)], and [CuCl2(un)] have been shown to exist in dilute acid solution (15, 67, 138). 

HCN adds more readily to alkynes than to alkenes.179 The addition of HCN to acetylene catalyzed by Cu+ ions was once a major industrial process to manufacture acrylonitrile carried out in the presence of copper(I) chloride, NH4CI, and HC1180 (see Section 6.2.4). Zerovalent Ni and Pd complexes are effective catalysts... 

In one step of the industrial process for producing copper from chalcopyrite (CuFeS2), molten copper sulfide is reduced with a blast of hot air ... 

The Wacker Oxidation is an industrial process, which allows the synthesis of ethanal from ethene by palladium-catalyzed oxidation with oxygen. Copper serves as redox cocatalyst. 

A major industrial process that uses skeletal copper catalysts is the liquid-phase hydrolysis of nitriles to... 

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