Bureau of Mines / Minerals yearbook metals, minerals, and fuels 1972
Year 1972, Volume 1 (1972)
Magnesium, pp. 735-745 ff. PDF (829.8 KB)
744 MINERALS YEARBOOK, 1972 of partially anhydrous magnesium chloride from magnesium chloride solution. The metal production process involves the electrolysis of anhydrous magnesium chloride in a fused salt bath at 700° C. Japan.—M'itsubishi Chemical Industries Co., Ltd., abandoned its plans to build a small electrolytic magnesium plant in Japan. The original plans had called for an electrolytic plant with an initial capacity of 5,000 tons per year of magnesium. Netherlands.—Shell Minerals Netherlands NV (Shell) announced that it decided to postpone indefinitely its magnesium chloride project in the Friesland province of the country. Shell stated that it had suitable processing technology for magnesium, but that it was still too costly. Also, world prices for light metals, especially for aluminum, were depressed and that there was no prospect of a recovery in the near future. The Netherlands Economics Ministry in The Hague said that Shell would not be given the production license it applied for 1½ years ago in view of the company's decision to shelve the project. The award had been delayed a number of times due to local opposition on environment-protection and pollution grounds. The Economics Ministry added that, in view of the importance of the project for the economic development of the northern provinces of the Netherlands, it intended to set up an independent group to study other possibilities for exploiting the magnesium in the short term. Shell agreed to place the necessary technical information at the group's disposal. Norway.—The Magnesium Division of Norsk Hydro A/S created a special 20-man technical staff to engage in technical marketing and to develop new applications for magnesium. The technical staff reported potential in the fields of alloying, electroplating, pressure die casting magnesium, and organic synthesis. U.S.S.R.—The estimated production of magnesium metal in 1972 was 60,000 short tons, a 3,000-ton increase over 1971 production. According to the Soviet weekly ECOTASS, Russian magnesium exports reached 19,900 tons in 1972, a 34% increase compared with the 14,800 tons shipped in 1971. TECHNOLOGY The research laboratories of Alcoa developed a process whereby the magnesium content of aluminum scrap is reduced from about 0.5% to 0.1%.2 Conventional methods to reduce the magnesium content of scrap produced chloride fumes. Alcoa's Fumeless Demagging Process, a pollutionfree process, reportedly lowers operating costs and produces 99% pure magnesium chloride, a salable byproduct. The process involves the reaction of magnesium and chlorine by multiple-stage gas-liquid contacting in a closed reactor-settler tank, eliminating wet or dry scrubbers and dust filters. The operating costs are approximately one-third of those for chlorine fluxing and scrubbing systems. The capital cost is estimated at $75,000 for a system to remove magnesium from 24 million pounds per year of alloy scrap. The process is currently being installed at Alcoa's Davenport,' Iowa, smelter where it will be used for in-plant wrought alloy scrap. To prevent molten magnesium from oxidizing on contact with air, the molten metal is presently covered with a mixture of fine potassium and magnesium chloride powder. The Magnesium Research Center at Battelle Memorial Institute announced a $160,000 research program on the fluxless melting of magnesium which may possibly reduce the cost of casting magnesium by 4 cents per pound. Data from laboratory experiments as well as from commercial operations indicate that sulfur hexafluoride (SF6) was a practical oxidation inhibitor for molten magnesium.3 The optimum concentration of SF6 in air for most efficient protection of molten magnesium is 1/10% or less. Research by Bureau of Mines investigators showed that yields of vanadium in excess of 98% can be achieved by reducing 2 Chemical Week. New Process That Solves Aluminum Can Recycling Problems. V. 111, No. 8, Aug. 23, 1972, p. 24. Hanawalt, J. D. Practical Protective Atmospheres for Molten Magnesium. Metals Engineer,ng Quarterly, November 1972.
http://rightsstatements.org/vocab/NoC-US/1.0/| As a work of the United States government, this material is in the public domain.| For information on re-use see: http://digital.library.wisc.edu/1711.dl/Copyright