Molybdenum mine production

World molybdenum production has increased from about 90 metric tons in 1900 — half from Australia and Norway, half from the United States — to 136 tons in 1906, 1364 in 1932 (an order of magnitude increase in 26 years), 10,909 in 1946, and 91,000 tons in 1973. Through the years, molybdenum has been produced in about 30 countries. In 1973, about 60% of the worldwide production was from the United States, 15% from Canada, 15% from the U.S.S.R. and China combined, and 10% from other nations — Chile, Japan, Korea, Norway, and Mexico (King et al. 1973). By 1979, the United States produced about 62% of the world production of 103,000 metric tons, and exported about half, chiefly to western Europe and Japan other major producers in 1979 were Canada, Chile, and the U.S.S.R. (Kummer 1980). In the United States, only three mines in Colorado account for almost 70% of domestic production. Other active molybdenum mining sites in North America are in Arizona, Nevada, New Mexico, Utah, and California molybdenum reserves have also been proven in Idaho, Alaska, Pennsylvania, and British Columbia (Kummer 1980). About 65% of domestic molybdenum is recovered from ores rich in molybdenum the rest is a byproduct from ores of copper, tungsten, and uranium (Chappell et al. 1979). 

Silvermigration, 9 824 Silver metallization, electroless, 9 697 Silver mine production, worldwide, 22 645t Silver molybdenum oxide, 22 671 Silver nitrate, 22 671-672, 22 672 addition in ruby glass manufacture, 7 344... 

The molybdenum supply in the Western world can be broken down into primary mine production (40%), byproduct, or coproduct output from copper and scheelite mines (55%), imports (from the People s Republic of China) 3%, and molybdenum recovered from the processing of spent petroleum catalysts (2%). 

Molybdenum is also recovered as a by-product of copper and tungsten mining operations. The metal is prepared from the powder made by the hydrogen reduction of purified molybdic trioxide or ammonium molybdate. 

In the early 1980s mine capacity approached a level of 136,000 t/yr Mo, far more than demand. Several mines have since closed. As of the early 1990s total molybdenum capacity remained well above total demand of about 90,000 t/yr. Estimated 1993 production in units of metric ton of molybdenum was in Armenia, 450 t in Canada, 10,000 t in Chile, 15,000 t in China, 16,000 t in Iran, 1,400 t in Kazakhstan, 1,400 t in Mexico, 1,800 t in MongoHa, 1,400 t in Pern, 2,700 t in Russia, 5,000 t in Uzbekistan, 900 t and in the United States, 37,000 t. 

Before scmbbing procedures were estabUshed for copper ore, most of the rhenium was lost as the volatile (Re202). A small portion, perhaps 10%, was retained in flue dust, which was processed to give the metal. A commercial flotation (qv) process for the recovery of the molybdenite by-product is available that permits a high recovery of molybdenum and rhenium. This process is used at the Caridad copper mine in Mexico. 

Revenues from low grade copper mines are also gained from such by-products as molybdenum [7439-98-7] silver, gold, selenium [7782-49-2] and tellurium [13494-80-9],... 

A U.S. Bureau of Mines survey covering 202 froth flotation plants in the United States showed that 198 million tons of material were treated by flotation in 1960 to recover 20 million tons of concentrates which contained approximately 1 billion in recoverable products. Most of the worlds copper, lead, zinc, molybdenum, and nickel are produced from ores that are concentrated first by flotation. In addition, flotation is commonly used for the recoveiy of fine coal and for the concentration of a wide range of mineral commodities including fluorspar, barite, glass sand, iron oxide, pyrite, manganese ore, clay, feldspar, mica, sponumene, bastnaesite, calcite, garnet, kyanite, and talc. 

Primary Mined particularly for the molybdenum contained in the ores. In some instances, molybdenum could be the only valuable metal recovered from the ore. The Questa deposit in New Mexico is mined exclusively for molybdenum content. In other deposits molybdenum may be the main product recovered together with one or more products. In these deposits the molybdenum content alone would allow for a profitable operation. The ore at the Climax mine in Colorado is of this type. Currently, monazite, pyrite, tin, and tungsten are recovered from the ore none of these by-products exists singly nor together in sufficient quantity so that the ore could be mined profitably merely for the extraction of one or all of these by-products. 

By-product of copper ores By-product reserves of copper ores are those contained in ores that are or would be mined mainly for the copper content. Molybdenum recovery occurs as a by-product or secondary product during processing of the ore for the recovery of copper. 

Co-product of copper molybdenum ores In these ores neither copper nor molybdenum occurs in large enough quantity for the ore to be mined profitably for the extraction of just one. Operation would be profitable when both are recovered. 

CARBIDES-INDUSTRIALHARD CARBIDES] (Vol 4) - [MOLYBDENUM AND MOLYBDENUMALLOYS] (Vol 16) -beryllides of [BERYLLIUM COMPOUNDS] (Vol 4) -catalyst [MALONIC ACID AND DERIVATIVES] (Vol 15) -by-products of copper mining [COPPER] (Vol 7)... 

Prior to 1925 the production of molybdenum was very irregular. It was only about 100 tonnes in 1914, reached 8,000 tonnes in 1918, and virtually ceased from 1920 to 1925. Since then it has increased dramatically , to 2,200 tonnes in 1933, 9,000 tonnes in 1938, 31,000 tonnes in 1943, 58,000 tonnes in 1966, and more than 100,000 tonnes by 1989. During the nineteen seventies the demand for molybdenum in the Western world had outstripped the supply , as shown in Table 2.2, and several important new mines were brought into operation. 

Molybdenum is obtained as a by-product of copper mining or is mined directly (primary deposits are in the Rocky... 

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