Molybdenum and copper

Flotation or froth flotation is a physicochemical property-based separation process. It is widely utilised in the area of mineral processing also known as ore dressing and mineral beneftciation for mineral concentration. In addition to the mining and metallurgical industries, flotation also finds appHcations in sewage treatment, water purification, bitumen recovery from tar sands, and coal desulfurization. Nearly one biUion tons of ore are treated by this process aimuaHy in the world. Phosphate rock, precious metals, lead, zinc, copper, molybdenum, and tin-containing ores as well as coal are treated routinely by this process some flotation plants treat 200,000 tons of ore per day (see Mineral recovery and processing). Various aspects of flotation theory and practice have been treated in books and reviews (1 9). 

Allen, J.D. and J.M. Gawthome. 1987. Involvement of the solid phase of rumen digesta in the interaction between copper, molybdenum and sulphur in sheep. Brit. Jour. Nutr. 58 265-276. 

Suttle, N.F. 1980. The role of thiomolybdates in the nutritional interactions of copper, molybdenum, and sulfur fact or fantasy Ann. N.Y. Acad. Sci. 355 195-207. 

In the USSR Kovalsky showed that productivity in cattle can be correlated to the excess or deficiency of boron, cobalt, copper, molybdenum and selenium in animal feed. Similar studies were carried out in England and Ireland by Webb (Webb, 1964 Webb et al., 1966) and in USA, by Ebens (Ebens and Schaclette, 1982). 

Strontium, barium, manganese, copper, molybdenum, and nickel are elements of strong accumulation in plant species of African Savanna ecosystems, in spite of different content in soils and soil-forming rocks. The Cb values are >1. The other elements, like beryllium, zirconium, titanium and vanadium, are less taken up by plants and their Cb values are less than 0.5. These refer to various exposure pathways to both microbes and plants as links in biogeochemical food webs. 

Riest, U., Ronning, M., Dunkley, W. L. and Franke, A. A. 1967. Oxidative stability of milk as influenced by dietary copper, molybdenum and sulfate. Milchwissenschaft 22, 551-554. 

The titanium-base alloys are considerably stronger than aluminum alloys and superior to most alloy steels in several respects. Several types are available. Alloying metals include aluminum, vanadium, tin, copper, molybdenum, and chromium. 

Minor nutrients Salts of iron, manganese, zinc, boron, copper, molybdenum, and cobalt in trace amounts. 

Experimental studies have been carried out in field locations in China. These studies include soil traverses over iron, copper, molybdenum and lead-zinc deposits, as well as a 20 km regional traverse and a regional grid. The results show significant anomalies above mineralisation, with low background values and good contrast. Both Hg, and Hg, contribute to indicating the location of buried mineral deposits. 

Figure 10 shows the distribution of zinc and arsenic in coal samples of the Illinois basin. The data are shown as circles whose size is proportional to the element s content on a whole coal basis. The data shown were compiled from Gluskoter (1977), Oman et al. (1992) and Bragg et al. (1991) and are listed in Affolter and Hatch (2002). Zinc in Illinois Basin coal ranges up to 10,000 ppm and arsenic up to 950 ppm. In addition to zinc and arsenic, data from the sources listed above shows that the elements lead, barium, cadmium, cobalt, copper, molybdenum, and nickel are also significantly enriched over average values for U.S. coal. 

A similar phenomenon has been observed with rats exposed to ozone. When the rats were exposed to this pulmonary irritant for 4 h, the animals showed increased levels of copper, molybdenum, and zinc in the lungs, while these metals were decreased in the liver. This would indicate an altered hemodynamics and changes in cellular permeability in a secondary affected organ. 

A number of methods exist for the determination of parts-per-billion (ng/g) levels of chromium in aqueous media (Table 8.1). These are repeatedly reviewed as new techniques are introduced (4,5,6). Potentially all these techniques could be applied to petroleum samples after matrix destruction, but in practice, only a few have been utilized. After wet oxidation of a large sample (> 100 g), 10 to 50 fig of chromium may be determined by a colorimetric procedure with 1,5-diphenylcarbohydrazide after iron, copper, molybdenum, and vanadium are extracted as the cup-ferrates (3). In survey analyses, Cr levels as low as 5 ng/g have been measured by optical emission spectroscopy after ashing (2,3) or directly by neutron activation with extended irradiation and counting times (1). Concentrations of chromium above 100 ng/g in used lubricating oils have been measured directly by flame atomic absorption (8) for lower concentrations, heated vaporization atomic absorption (HVAA) has been utilized (9). In the Trace Metals Project, two procedures using this latter technique were evaluated for the determination of 10 ng Cr/g in a variety of petroleum matrices. 

In contrast, the manganese, copper, molybdenum and nickel concentrations of... 

Oxides of copper, molybdenum, and vanadium had a disastrous effect on the carriers. Surface area dropped to less than 10 m2/g, and crushing strength was much less than that of the original sample. Degradation by molybdenum oxide is well known at 600°C aluminum molybdate is formed and decomposes at about 800°C into a-Al203 and M0O3 which sublimates. 

Clawson, W. J. (1972). Copper, molybdenum and selenium in the west. In Proceedings of the Nevada-California Beef Conference. Reno University of Nevada. 

Highmoor peat soils of New Zealand, formerly considered as waste lands, have, as a result of research by Hupkens van der Elst (1962), been shown to be capable of being used as high-producing pastures. Additions of Ume, phosphorus, potassium, and nitrogen, as well as copper, molybdenum, and sometimes iron, are required. Zinc and boron are also needed by certain crops. 

Kinnamon KE. 1963. Some independent and combined effects of copper, molybdenum, and zinc on the placental transfer of zinc-65 in the rat. J Nutr 81 312-320. 

B. de la Cruz, Neutron Activation Analysis of Copper, Molybdenum and Zinc in Relation to a Study of Trace Elements in Cardiovascular Diseases, Technical Report of the Research Coordination Meeting on Trace Elements in Relation to Cardiovascular Diseases, International Atomic Energy Agency, Vienna, 1973, pp. 19-27. 

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