Alternatives for Producing Hafnium-Free Zirconium from Zircon

9 ALTERNATIVES FOR PRODUCING HAFNIUM-FREE ZIRCONIUM FROM ZIRCON 

Die foregoing processes for extracting zirconium from zircon, separating zirconium from hafnium, and reducing zirconium compounds to metal can be combined in a number of ways, some of which are shown in Fig. 7.15. The combination of processes used in the United States in 1978 is at the left of this figure. 

American Society for Testing and Materials 1976 Annual Book of ASTM Standards part 8, Nonferrous Metals-Nickel, Lead and Tin Alloys, Precious Metals, Primary Metals Reactive Metals, American Society for Testing and Materials, Philadelphia, 1976. 

Ampian, S. G. In Minerals Yearbook, 1974, vol. I, Metrds, Minerals and Fuels, U.S. Government Printing Office, Washington, D.C., 1976, pp. 1397-1415. 

Mueller Zirconium Hydrides and Hafnium Hydrides, in Metal Hydrides, W. M. Mueller, J. P. Blackledge, and G. G. Libowitz (eds.). Academic Press, New York, 1968, chap. 7. 

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