Everything about The Crystal Bar Process totally explained
The
crystal bar process (or
iodide process) was discovered by
Anton Eduard van Arkel and
Jan Hendrik de Boer in 1925. It is also known as the van Arkel - de Boer process. This process was the first industrial process for the commercial production of pure ductile metallic
zirconium. It is used in the production of small quantities of ultra-pure titanium and zirconium. It primarily involves the formation of the metal iodides and their subsequent decomposition to yield pure metal. This process was superseded commercially by the
Kroll process.
Impure titanium or zirconium is heated in an evacuated vessel with iodine at 50-250
oC. Titanium or zirconium iodide (TiI
4 or ZrI
4) is formed and is volatilized (leaving impurities as solid). At atmospheric pressure TiI
4 melts at 150
oC and boils at 377
oC, while ZrI
4 melts at 499
oC and boils at 600
oC. The boiling points are lower at reduced pressure. The gaseous metal tetraiodide is decomposed on a white hot tungsten filament (1400
oC). As more metal is deposited the filament conducts better and thus a greater electric current is required to maintain the temperature of the filament.
Further Information
Get more info on 'Crystal Bar Process'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://crystal_bar_process.totallyexplained.com">Crystal bar process Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |