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Generally, the crystal bar process can be performed using any number of metals using whichever halogen or combination of halogens is most appropriate for that sort of transport mechanism, based on the reactivities involved. The only metals it has been used to purify on an industrial scale are
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filament (1400 °C). As more metal is deposited the filament conducts better and thus a greater electric current is required to maintain the temperature of the filament. The process can be performed in the span of several hours or several weeks, depending on the particular setup.
258:. Now it is used in the production of small quantities of ultrapure titanium and zirconium. It primarily involves the formation of the metal iodides and their subsequent decomposition to yield pure metal, for example at one of the
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melts at 499 °C and boils at 600 °C. The boiling points are lower at reduced pressure. The gaseous metal tetraiodide is decomposed on a white hot
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titanium, zirconium and hafnium, and in fact it is still in use today on a much smaller scale for special purity needs.
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Van Arkel, A. E.; De Boer, J. H. (1925). "Darstellung von reinem
Titanium-, Zirkonium-, Hafnium- und Thoriummetall".
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at 50–250 °C. The patent specifically involved the intermediacy of
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Process for the commercial production of pure titanium and zirconium
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As seen in the diagram below, impure titanium, zirconium,
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melts at 150 °C and boils at 377 °C, while ZrI
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An apparatus used for the process. The main body is
362:Zeitschrift für anorganische und allgemeine Chemie
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265:This process was superseded commercially by the
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246:and some other metals. It was developed by
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305:is heated in an evacuated vessel with a
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173:Shaping processes in crystal growth
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143:Fractional crystallization
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469:. You can help Knowledge by
163:Laser-heated pedestal growth
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326:At atmospheric pressure TiI
153:Hydrothermal synthesis
118:Bridgman–Stockbarger method
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531:Methods of crystal growth
228:van Arkel–de Boer process
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123:Van Arkel–de Boer process
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374:10.1002/zaac.19251480133
148:Fractional freezing
556:20th-century inventions
541:Metallurgical processes
128:Czochralski method
465:-related article is a
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260:Allegheny Technologies
248:Anton Eduard van Arkel
105:Methods and technology
440:U.S. patent 4,487,629
427:U.S. patent 1,709,781
414:U.S. patent 1,718,616
401:U.S. patent 1,666,800
388:U.S. patent 1,582,860
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516:Industrial processes
230:, also known as the
252:Jan Hendrik de Boer
236:crystal-bar process
97:Single crystal
77:Crystal growth
551:1925 introductions
536:Titanium processes
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168:Micro-pulling-down
546:Materials science
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262:' Albany plants.
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158:Kyropoulos method
87:Seed crystal
82:Recrystallization
51:Crystal structure
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188:Zone melting
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38:Fundamentals
138:Flux method
510:Categories
347:References
256:Philips Nv
56:Nucleation
521:Zirconium
244:zirconium
463:industry
336:tungsten
295:vanadium
240:titanium
64:Concepts
307:halogen
299:thorium
291:hafnium
285:Process
133:Epitaxy
46:Crystal
113:Boules
461:This
467:stub
316:and
250:and
226:The
370:doi
366:148
318:ZrI
311:TiI
301:or
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