Talk:Scandium
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Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 14:18, 2 July 2005 by Femto (previous revision was that of 13:05, 12 June 2005).
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[edit] Information Sources
Some of the text in this entry was rewritten from Los Alamos National Laboratory - Scandium. Additional text was taken directly from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table were obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but were reformatted and converted into SI units.
[edit] Talk Proper
Under the applications heading "...used in indoor or night-time color televisions." What does this mean? Someone, please clarify
- That should not say "in" (television) but "with" (camera color reproduction), I guess. Reorganized the section. Femto 14:02, 20 Mar 2005 (UTC)
[edit] Reduction to metal
The language
- In 1937 metallic scandium was prepared for the first time by electrolysis of a eutectic melt of potassium, lithium, and scandium chlorides at 700 to 800° C.
is ambiguous, suggesting that perhaps the metal was prepared earlier than 1937, by other means. I am recasting the sentance without being absolutely certain, to save others wondering, since the plausible alternative is unlikely to have been expressed this way.
--Jerzy (t) 02:21, 2005 Mar 29 (UTC)
The language
- Tungsten wire in a pool of liquid zinc were the electrodes in a graphite crucible.
is ungrammatical and too vague in general. Can someone who understands what it is trying to communicate recast it, to state clearly
- two identical electrodes, each consisting of a W wire immersed in a pool of molten Zn, or
- one W wire electrode, and one pool of Zn, or
- something else.
Personally i'm picturing
- a graphite crucible containing eutectic chloride melt;
- two pools of Zn floating on the chloride melt, or in hollows below it at the bottom of the crucible;
- each pool making contact with both a W wire and the adjacent chloride melt;
- Sc metal accumulating at one of the melt-Zn interfaces;
- probably Sc metal being scraped off the solidified Zn and/or chloride melt after the apparatus was permitted to cool.
But i ain't gonna stick my neck out that far in the article.
--Jerzy (t) 02:21, 2005 Mar 29 (UTC)
Actually, the melt is ambiguously described as well:
- Sc chlorides mixed with K & Li, or
- Sc chloride mixed with multiple chlorides of K and Li, or
- a mixture containing the chloride of each of Sc, K, and Li.
Again, those better informed could clarify.
--Jerzy (t) 02:43, 2005 Mar 29 (UTC)
[edit] Independent discovery by Cleve
This appears mostly in WP-based sources, perhaps including periodic-table.org.uk which confusedly contrasts (as if two discoveries of different substances; emphasis added by Jerzy)
- Scandium was discovered by Lars Nilson in 1879. Per Teodor Cleve discovered scandium oxide at about the same time as Nilson.
Trivia-library quotes the curt and ambiguous "The People's Almanac" series:
- Predicted by Dmitri Mendeleev of Russia in 1871. Lars Nilson of Sweden discovered its oxide in 1879, and Per Teodor Cleve of Sweden identified it later in that year.
Rare Earth Elements on the Web cites other independent element discoveries, but not this supposed one.
Ask Dr Rob says
- 1840 Swedish chemist Lars Frederik Nilson born (died 1899). He discovered the element scandium, which he named after his native Scandinavia.
- 1840 Swedish chemist Per Teodor Cleve, discoverer of the elements thulium and holmium born (died 1905).
The idea is likely to be the result of confusing Cleve's discovery that Sc matches Eka-B with an independent discovery. E.g., EB 1911 and Michael D. Gordin, A Well-Ordered Thing, p. 40 mention the inference but not discovery or isolation. Gordin in fact quotes Cleve (emphasis added by Jerzy)
- I have the honor to inform you that your element eka-boron has been isolated. It is scandium, discovered by Nilson....
and makes a point not about Cleve working on that particular rare earth but about his being another Swede, making accessible to him what was not to Mendeleev.
I'm removing his supposed discovery of the element, pending a solid citation.
--Jerzy (t) 10:54, 2005 Mar 29 (UTC)
Note that the bio Per Teodor Cleve has never endorsed this presumed error (tho it also has not mentioned his undisputedly real role).
--Jerzy (t) 15:54, 2005 Mar 29 (UTC)
[edit] Precautions
I've temporarily removed the small Precautions section from the article:
NFPA 704
Scandium burns easily, so flammibility number is incorrect. Someone please change 0 to 2. Thank you.
Both the NFPA diamond and the assertion that it is incorrect are unsourced and I've been unable to find info such as an MSDS for pure scandium to back up either claim. So I've moved it here until it can be verified one way or another. --Ed (Edgar181) 16:16, 22 November 2006 (UTC)
[edit] Percentage in alloys
I have removed the last part of the sentence "at the rate of 2-5% Sc.[1]" from the Scandium market section. The 2-5% mentioned in the source is for the master alloy, which is them further diluted with the main alloy metal (aluminium) to make the final alloy product. Source is http://www.theodoregray.com/PeriodicTable/Elements/021/index.s7.html in the Aluminum-scandium master alloy section. Perhaps someone with knowlege of the final percentage used in alloys can enter this data.
Apologies for putting this in here as I'm not sure how to edit the pages properly. Just some more information.
I'm Tim Worstall and I'm mentioned elsewhere in Wikipedia as being part of the "international scandium oligopoly".
So a few bits and pieces.
That $600 price per kg is for the oxide, Sc2O3. As a rough and ready guide to value that's fine.
Finished alloys tend to be 0.1% to 0.2% scandium by weight. The 2% refers to the standard grade of the master alloy.
I would hesitate to say that scandium is "rare". It's rare to find it in any concentrated form, yes, and there are very few people who extract it from these diffuse sources. But in terms of the tonnage potentially available it isn't rare.
Light bulbs: almost all metal halide bulbs (some 100 million a year) use a sodium/scandium iodide phosphor. It's not just TV lighting. It provides "sunlight" to the spectrum of emissions.
Very little scandium is as yet used in aircraft, other than a few late Soviet designs. There might be a future use in making wings and fuselages. Two different things there. Look in a patent database for "Lenzowski + scandium" and you should find the Airbus one about wing surfaces. "A. Norman + friction stir welding" might find the one about fuselages.)
Thortveitite and kolbeckite are NOT the primary sources. No extraction has been done from these for at least a decade. There is some from Chinese rare earth mines, yes. The uranium mine tailings...not in the Ukraine at all. In Kazakhstan. There's been a long running story about the world's only scandium mine in the Ukraine and it is just that, a story. There was indeed an iron ore mine that (Zhivty Vod from memory) wished to extract it but they only ever produced a few kilos.
Further, it's not so much mine tailings, rather, the use of a technique called in situ leaching that enables Sc to be extracted from the uranium ore.
I would be amazed if there's any extraction as a result of nickel cobalt copper or PGE mining. I certainly don't know of any, although I also agree that it is possible.
Use as much or as little as you wish.
