O que está realmente em movimento
Heavy rare earths do not come from a conventional orebody. They come from weathered granite where the metal ions cling loosely to clay, and they are recovered by washing a salt solution through the hillside. The grade is tiny; the strategic weight is enormous.
- O material
- Dysprosium
- A variedade
- Ion-adsorption clay, very low grade, unusually rich in heavy rare earths
- Onde começa
- China — Weathered granite hills in Jiangxi, Guangdong and Fujian
Passo a passo, e fronteira a fronteira
China · Jiangxi and Guangdong detido por State-consolidated producers (Produtor estatal)
Leaching the hill in place
Ammonium sulfate solution is injected into the weathered granite and collected downslope. The rare-earth ions swap places with ammonium on the clay and come out in solution. Nothing is blasted and, in modern practice, little is dug.
O que aconteceu ao restante: Older, uncontrolled in-situ leaching left serious groundwater and slope-stability damage, which is much of why the industry was consolidated under state control.
Por que aqui: This deposit type needs a specific granite, a specific climate and millions of years. It is not a matter of looking harder elsewhere.
China · On site detido por Producers (Químico)
Precipitating a mixed carbonate
The pregnant solution is precipitated into a mixed rare-earth carbonate — the intermediate everything downstream starts from.
Por que aqui: Concentrating before transport, as always.
China · Ganzhou, Jiangxi detido por China Rare Earth Group and affiliates (Refinador)
Separating the heavies
Solvent extraction, but far harder than for the light rare earths: dysprosium, terbium, holmium and erbium are even more alike than neodymium and praseodymium, so it takes more stages and more patience.
O que aconteceu ao restante: Terbium, yttrium, gadolinium and the rest come out alongside. Yttrium is by far the largest fraction; dysprosium and terbium are the ones everyone actually wants.
Por que aqui: Heavy separation capacity is concentrated here to a degree unmatched by any other material in this atlas.
China · Magnet plants detido por Magnet manufacturers (Fabricante)
Diffused into a magnet's grain boundaries
Rather than alloying dysprosium throughout the magnet, it is painted on and diffused into the grain boundaries where it does the most good. The technique cut dysprosium use per magnet several-fold.
O que aconteceu ao restante: This is substitution by engineering rather than by chemistry — same performance, a fraction of the scarce element.
Por que aqui: Grain-boundary diffusion is a process advantage held by a small number of manufacturers.
Germany · Traction motors and turbines detido por Motor manufacturers (Fabricante)
A motor that can get hot
Without dysprosium a neodymium magnet begins losing strength around 80 °C. A traction motor or a turbine nacelle routinely runs hotter than that. 15 kg is enough for several thousand car motors.
Por que aqui: A few kilograms of a metal from a Chinese hillside is what lets an electric motor survive a summer traffic jam.
Este é um exemplo elaborado. Acompanha uma quantidade inicial declarada através de rendimentos e recuperações típicos publicados, pelo que as proporções são verificáveis; não é o registo de uma remessa específica. Os factos relativos à rota — quais os países, quais os processos e por que o material não pode simplesmente ser tratado noutro local — são compilados a partir de informação pública.