Japan team maps 'semi-infinite' rare earth reserves - Page 1
Forum section: electronics / general

author: splin
author_rank: Frequent Contributor
timestamp: April 12, 2018, 09:01:23 am
content: https://phys.org/news/2018-04-japan-team-semi-infinite-rare-earth.htmlEncouraging news to prevent China holding the world to ransom for many important materials. Let's hope they can be recovered economically without significant ecological damage though I doubt either is a given.

author: BravoV
author_rank: Super Contributor
timestamp: April 12, 2018, 09:23:14 am
content: As both countries developed love & hate through decades, China politically can make a nasty move to dump it globally that made the price falls like a rock, if Japan invested heavily on the mining infrastructure that will affect on long term profitability, leaving a joint venture or China acquisition as one of the options.

author: IanMacdonald
author_rank: Frequent Contributor
timestamp: April 12, 2018, 10:29:09 am
content: I think Japan will be more careful about the ecological aspect. China never has cared two hoots about the environment.

author: filssavi
author_rank: Frequent Contributor
timestamp: April 12, 2018, 11:35:07 am
content: The problem with rare earths is not their rarity (the name is kind of a misnomer) Neodymium is in fact about as rare as copper or nickel, the big problem of rare earths is that they are only found alloyed together and their similarity makes purification exceedingly difficult and polluting, so unless new greener separation techniques are found I don’t see the situation changing anytime soon.The only truly rare rare earth is promethium because it is a radioactive element with a relatively short half life (at most 3/4 years)

author: raptor1956
author_rank: Frequent Contributor
timestamp: April 13, 2018, 08:56:16 pm
content: Quote from: BravoV on April 12, 2018, 09:23:14 amDid you even read the article -- "That came after Japan arrested the captain of a Chinese trawler that was involved in a run-in with Japanese coastguards near the disputed Senkaku Islands, claimed by China as the Diaoyus."So, I don't think Japan will be bending over backwards to assist China in maintaining a stranglehold on rara earths.Brian

author: Kleinstein
author_rank: Super Contributor
timestamp: April 14, 2018, 08:28:56 am
content: Quote from: filssavi on April 12, 2018, 11:35:07 amThat is an very important point. Producing rare earth materials is more about chemistry than about mining.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 14, 2018, 09:24:38 am
content: In case anyone was wondering, the concentrations are extremely low in seawater:http://oceanplasma.org/documents/chemistry.htmlIt's interesting that the article says the REY is mostly in biogenic minerals. It must be concentrated very strongly indeed, during and/or after life, for it to be magnified so strongly!I wonder how many years of deposits were measured (I didn't notice an estimate in the article). If very old, that could maybe explain the ability to concentrate so much.Alternately, if it's actually an ore body from some as-yet-unknown deposit or event, and the deposition rate is slow enough (evidently, ~cm / 1 kyr), maybe that's what they're seeing, or it's been chemically modified by water flow through the sediments. I guess it can't be too old, or nonuniform, because the depth they measured, should be about a million years old (at the bottom), and you'd expect stratification if there's an enrichment process going on in situ.Tim

author: filssavi
author_rank: Frequent Contributor
timestamp: April 14, 2018, 09:50:27 am
content: After some more digging (Out of curiosity) I was able to get a decent understanding (I hope) if the problemBasically it’s two separate problems that compound each other, the first is that the element concentration in the ore is very low (10% max) and thus it has to be processed to bring it up to 60/70%, by itself this is not too different from other mining processes, here is where the second problem comes into play, that is to say that there is no neodymium ore (for example) but just generic rare earths oxides with more or less everything inside, and since rare earths are physically and chemically all very similar a long series of acid whashes are necessary to selectively leach out all different componentsThis generates a vast amount of acid liquid wastes that are easier to release in the environment than to properly treat and neutraliseP.S. If someone with a better chemistry knowledge spots some errors fell free to correct them

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 14, 2018, 08:17:20 pm
content: Offhand, they'd probably start with as much sorting as they can, maybe a flotation/froth separation if feasible. Anything that enriches it without too much application of chemicals (including dissolving it wholesale). Then, it's probably dissolved. Sulfuric acid might be used, separating soluble REY sulfates from lower solubility acid phosphate (which can be sold as fertilizer). Maybe some further cleanup and concentration, and then on to the chromatography stages. (Ionically activated, porous plastic beads adsorb the ions at different rates, so that when the solution is pumped in one end, they come out the other end separated, sort of like fractional distillation.)It would be really cool if REY can be concentrated on a very specialized substrate. This would again use porous plastic beads, but functionalized with a specially shaped group that preferentially binds REY.) Then the process would be even simpler: filter the concentrated, dissolved ore over the substrate, then rinse, and elute with acid to free the REY salts in order. The depleted ore solution would probably be concentrated and sold as acid phosphate or phosphoric acid.But this is my speculation; if you're now more curious, you should be able to find real process information out there.Tim