Manganese deposits

Manganese-rich deposits usually take one of three forms A loosely adherent, friable, brown, or black deposit may occur (Fig. 4.5). A thin, dark, brittle, glassy manganese layer sometimes forms on heat transfer surfaces (Fig. 4.6). Nodular manganese deposits also occur (Fig. 4.7). Both nodular and glassy layers tend to occur on copper alloys. 

In some reports Gallionella have been associated with manganese and iron deposits that also contain chloride. It has been postulated that deep undercut pits on stainless steels (especially at welds) containing such deposits are indirectly caused by these bacteria, since the iron-manganese deposition can be accelerated by Gallionella. In spite of numerous literature citings, however, evidence for stainless steel... 

By far the most important ores of iron come from Precambrian banded iron formations (BIF), which are essentially chemical sediments of alternating siliceous and iron-rich bands. The most notable occurrences are those at Hamersley in Australia, Lake Superior in USA and Canada, Transvaal in South Africa, and Bihar and Karnataka in India. The important manganese deposits of the world are associated with sedimentary deposits the manganese nodules on the ocean floor are also chemically precipitated from solutions. Phosphorites, the main source of phosphates, are special types of sedimentary deposits formed under marine conditions. Bedded iron sulfide deposits are formed by sulfate reducing bacteria in sedimentary environments. Similarly uranium-vanadium in sandstone-type uranium deposits and stratiform lead and zinc concentrations associated with carbonate rocks owe their origin to syngenetic chemical precipitation. 

Murray JW, Brewer PG (1977) In Glasby GP (ed) Marine manganese deposits. Elsevier,... 

The importance of bacteria in mediating Mn(II) oxidation in certain environments is evident. But, the mechanisms whereby bacteria oxidize Mn(II) are poorly understood. Some bacteria synthesize proteins or other materials that enhance the rate of Mn(II) oxidation (.52). Other strains of bacteria require oxidized manganese to oxidize Mn(II) (53), suggesting that they may catalyse the oxidation of Mn(II) on the manganese oxide surface. Other bacteria may catalyse the oxidation of Mn(II) on iron oxide surfaces, as iron is associated with manganese deposits on bacteria collected in the eastern subtropical North Pacific (54). 

Glasby, G. P. "Marine Manganese Deposits," Elsevier, Amsterdam, 1977. 

Cronan, D. S. "Deep Sea Nodules Distribution and Geochemistry", p. 11 Mero, J. L. "Economic Aspects of Nodule Mining," p. 327 in Marine Manganese Deposits, Glasby, G. P., ed. Elsevier, Amsterdam, 1977. 

General distribution of Fe-Mn nodules in the Pacific and Atlantic oceans. Source-. From Kennett, J. (1982). Marine Geology, Prentice Flail, Inc., p. 500. After Cronan, D. S. (1977). Marine Manganese Deposits, Elsevier Science Publishers, pp. 11-44. 

Griffin W. L. and Mottana A. (1982). Crystal chemistry of clinopyroxenes form St. Marcel manganese deposit, Val d Aosta, Italy. Amer. Mineral, 67 568-586. 

Geochemical Characteristics of Sedimentary Manganese Deposit of Guichi, Anhui Province, China. Journal of Rare Earths, 24, 374-380. 

SiDWELL, K.O.J. 1957. The Woodstock, N.B., Iron - Manganese Deposits. Transactions Canadian Institute of Mining Metallurgy, 50, 411 16. 

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an additive in many commercial unleaded gasolines, and thus its potential effect on catalyst performance is an important consideration. It was reported by Faggan et al. 8) that MMT at a recommended level of 0.125 g Mn/gal shows no adverse effect on emissions, when compared to unleaded gasoline, in tests on cars operated on the 50,000-mile EPA certification schedule. These findings have been confirmed by a number of unpublished test reports from several industrial laboratories. In fact, it is indicated that some of the manganese deposits can aid catalytically in the removal of CO, and possibly to some extent also of hydrocarbons. The consequence of such a catalytic effect of Mn has still to be explored. 

Ghiorse, W.C., Biology of iron- and manganese-depositing bacteria, Ann. Rev. Microbiol., 38, 515, 1984. 

Murray, J. W. and Brewer, P. G., The mechanisms of removal of iron, manganese, and other trace metals from sea water. p. 291-326 Glasby, G. P., ed > "Marine Manganese Deposits," Elsevier, Amsterdam, 1977. 

Gair, J.E., 1973. Iron deposits of Michigan (United States of America). In Genesis of Precambrian Iron and Manganese Deposits. Unesco, Paris, pp. 365-375. 

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