World Molybdenum Metal Producers

Hampel, C.A. (ed.) ( 967) Rare Metals Handbook, 2nded. Reinhold, New York. 

Meyer-Grunow, H. (1997) Ferromolybdenum. In Habashi, F. (ed.) Handbook of Extractive Metallurgy, Vol. I. Wiley-VCH, Weinheim, pp. 477-480. 

Khodorovsky, Y. (1967) Production ofFerrolalloys. MIR, Moscow (transl. I.V. Savin). 

Osram Sylvania Products Hawes Street, Towanda, PA 18848, USA Telephone +1 (570) 268-5000 Fax +1 (570) 268-5113 URL http //www.sylvania.com/ 

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Molybdenum disulphide occurs naturally in very large quantities as the mineral molybdenite. Because of this ready availability, there is little incentive to develop any alternative sources, but small amounts have been produced synthetically, and the synthetic processes will be described later. Molybdenite is the most common naturally-occurring molybdenum compound, and the most important source of molybdenum metal. It occurs in many parts of the world, including the United States, Australia, Peru, Germany, Rumania, Canada and China. In 1915 two-thirds of the world s production was from Australia, but increased demand during the first world war led to the development of the huge deposits at Climax, Colorado, and these are now the principal source. 

Some molybdenum contain from 0.002% to 0.2% rhenium. More than 150,000 troy ounces of rhenium are now being produced yearly in the United States. The total estimated Free World reserve of rhenium metal is 3500 tons. Rhenium metal is prepared by reducing ammonium perrhentate with hydrogen at elevated temperatures. 

High density polyethylene (HDPE) is defined by ASTM D1248-84 as a product of ethylene polymerisation with a density of 0.940 g/cm or higher. This range includes both homopolymers of ethylene and its copolymers with small amounts of a-olefins. The first commercial processes for HDPE manufacture were developed in the early 1950s and utilised a variety of transition-metal polymerisation catalysts based on molybdenum (1), chromium (2,3), and titanium (4). Commercial production of HDPE was started in 1956 in the United States by Phillips Petroleum Company and in Europe by Hoechst (5). HDPE is one of the largest volume commodity plastics produced in the world, with a worldwide capacity in 1994 of over 14 x 10 t/yr and a 32% share of the total polyethylene production. 

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