Jerome a Paris: wikipediaAlthough it belongs to "rare earth metals," neodymium is not rare at all. It constitutes 38 ppm of the Earth's crust. I'm pretty sure it's not one tonne per turbine Maybe not.
Although it belongs to "rare earth metals," neodymium is not rare at all. It constitutes 38 ppm of the Earth's crust.
I'm pretty sure it's not one tonne per turbine
Maybe not.
is there enough outside of China to sustain a continued expansion of industry that is dependent on neodymium
Relatively speaking, Mountain Pass--whose rare-earth deposits were discovered in 1949--is not too radioactive, and through the 1950s the ore was mostly used to make flints for lighters. <...> ... in the early 1990s, cheaper Chinese rare earths began eating into the mine's market share. <...> As Chinese ore came onto the market, the price fell from $11,700 a ton in 1992 to $7,430 a ton by 1996 (in constant dollars). <...> Mountain Pass couldn't compete on price alone--especially given the mine's growing ecological costs. In 1998, chemical processing at the mine was stopped after a series of wastewater leaks. Hundreds of thousands of gallons of water carrying radioactive waste spilled into and around Ivanpah Dry Lake. ...
... in the early 1990s, cheaper Chinese rare earths began eating into the mine's market share. <...> As Chinese ore came onto the market, the price fell from $11,700 a ton in 1992 to $7,430 a ton by 1996 (in constant dollars). <...>
Mountain Pass couldn't compete on price alone--especially given the mine's growing ecological costs. In 1998, chemical processing at the mine was stopped after a series of wastewater leaks. Hundreds of thousands of gallons of water carrying radioactive waste spilled into and around Ivanpah Dry Lake. ...
On the second, probably not because there was already Nd mining before China began to expand Nd mining, increasing supply. But those lower prices, due to Chinese mining, do put a stop on Nd mining elsewhere. The mines listed in the diary above are currently not on-line because their current ore model is simply not profitable, partly because of environmental and labour regulations, but I wouldn't be surprised if the grade of the ore is lower as well.
But by all of this, I'd guess that building more wind turbines (if they really need that much Nd) would only stimulate industry elsewhere around the world.
Historically, mischmetal was prepared from monazite, an anhydrous phosphate of the light lanthanides and thorium. The ore was "cracked" by reaction at high temperature either with concentrated sulfuric acid, or with sodium hydroxide. Thorium was removed by taking advantage of its weaker basicity relative to the trivalent lanthanides, the radioactive radium isotope daughter products of thorium were precipitated out using entrainment in barium sulfate, and the remaining lanthanides were converted to the chloride. The resulting "Rare Earth Chloride" (Hexahydrate), sometimes known as "Lanthanide Chloride", was the major commodity chemical of the rare earth industry. By careful heating, preferably with ammonium chloride or in an atmosphere of hydrogen chloride, the hexahydrate could be dehydrated to provide the anhydrous chloride. Electrolysis of the molten anhydrous chloride (admixed with other anhydrous halide to improve the melt behavior) led to the formation of molten Mischmetal, which would then be cast into ingots. Any samarium content of the ore tended not to be reduced to the metal, but accumulated in the molten halide, from which it could later be profitably isolated. Monazite-derived Mischmetal typically was about 48% cerium, 25% lanthanum, 17% neodymium, and 5% praseodymium, with the balance being the other lanthanides. When bastnaesite started being processed for rare earth content in about 1965, it too was converted to a version of rare earth chloride, and on to Mischmetal. This version was higher in lanthanum and lower in neodymium. Currently (2007), the high demand for neodymium has made it profitable to remove all of the heavier lanthanides and neodymium (and sometimes all of the praseodymium as well) from the natural-abundance lanthanide mixture for separate sale, and to include only La-Ce-Pr or La-Ce in the most economical forms of Mischmetal. The light lanthanides are so similar in their metallurgical properties, that any application for which the original composition would have been suitable, would be equally well served by these truncated mixtures. The traditional "Rare Earth Chloride", as a commodity chemical, was also used to extract the individual rare earths by companies that did not wish to process the ores directly. Mischmetal is typically priced at less than 10 dollars per kilogram, and the underlying rare earth chloride mixtures are typically less than 5 dollars per kilogram (as of 2007).
Currently (2007), the high demand for neodymium has made it profitable to remove all of the heavier lanthanides and neodymium (and sometimes all of the praseodymium as well) from the natural-abundance lanthanide mixture for separate sale, and to include only La-Ce-Pr or La-Ce in the most economical forms of Mischmetal. The light lanthanides are so similar in their metallurgical properties, that any application for which the original composition would have been suitable, would be equally well served by these truncated mixtures. The traditional "Rare Earth Chloride", as a commodity chemical, was also used to extract the individual rare earths by companies that did not wish to process the ores directly. Mischmetal is typically priced at less than 10 dollars per kilogram, and the underlying rare earth chloride mixtures are typically less than 5 dollars per kilogram (as of 2007).
Rhône-Poulenc process of separation: Rhone-Poulenc, is the world No 1 rare earth producer, Rare earths are separated using a continuous separation process by extraction with solvents. Solubilization: in the Rhone-Poulenc plant in La Rochelle (17), monazite (or any other rare earth minerals), after grinding, is attacked by soda (NaOH)to 60% by mass to 180 ° C, autoclave for about 3 hours. The formed Trisodium phosphate (Na3PO4) solution is removed with hot water. Hydroxides of rare earths and thorium, after filtration and washing are dissolved in nitric acid. Step 2: Rare earth separation / thorium-uranium / impurities: by liquid-liquid separation units. Thorium nitrate (99.9%) and uranium nitrate are produced at this stage. Effluents are radioactive and are treated and the residues are stored. Until 1991, these wastes, low-level radioactive, were stored on the ANDRA La Hague site (for France) near the plant for the reprocessing of spent fuel at La Hague (see Uranium). Since this site is now saturated they are now stored temporarily in Cadarache. Faced with the difficulties in storing such waste, Rhone-Poulenc decided to change its supply of ore. Instead of monazite imported from Australia, since late 1994, the ore used (bastnasite) is pretreated at the place of extraction (Bayun Oba, China and Mountain Pass, United States) before extraction of rare earths to La Rochelle. Step 3 Separation of rare earths: again with solvent extraction units, lanthanum (at 99,995% purity) is extracted, and cerium (99.5%), the DIDYME (Nd-Pr alloy composed of Pr and 98% to 95% Nd) [note: the very names for Pr and Nd comes from ancient greek "twins" (dyme), illustrating the difficulties in separating them. Indeed, they were considered at first as only one element], samarium / europium (separated into 98% Sm and Eu 99.99%), the gadolinium / Terbium (separate then 99.99% Gd and Tb in 99.9%), and all other rare earths, yttrium is obtained, after extraction, 99.99%. During the various extractions, many types of solvents are used: acid di (2-ethylhexyl) phosphate, tri (n-butyl) phosphate, quaternary ammonium salts, carboxylic acids ... In the factory of La Rochelle, more than 1 500 steps of mixer-settlers treatment are used. Rare earths are separated delivered in the form of oxides or salts, the purity is, in general, expressed in mass compared to other rare earths, regardless of any other impurities present. Step 4: Metals and especially neodymium, yttrium and terbium, are prepared by calciothermie to over 1 000 ° C, from the fluoride in the case of neodymium according to the reaction: 2NdF3 + 3 Ca ---> 2Nd + 3CaF2 These operations are metallurgical, Rhône-Poulenc, conducted in the United States, Phoenix (Arizona)
Solubilization: in the Rhone-Poulenc plant in La Rochelle (17), monazite (or any other rare earth minerals), after grinding, is attacked by soda (NaOH)to 60% by mass to 180 ° C, autoclave for about 3 hours. The formed Trisodium phosphate (Na3PO4) solution is removed with hot water. Hydroxides of rare earths and thorium, after filtration and washing are dissolved in nitric acid.
Step 2: Rare earth separation / thorium-uranium / impurities: by liquid-liquid separation units. Thorium nitrate (99.9%) and uranium nitrate are produced at this stage. Effluents are radioactive and are treated and the residues are stored. Until 1991, these wastes, low-level radioactive, were stored on the ANDRA La Hague site (for France) near the plant for the reprocessing of spent fuel at La Hague (see Uranium). Since this site is now saturated they are now stored temporarily in Cadarache. Faced with the difficulties in storing such waste, Rhone-Poulenc decided to change its supply of ore. Instead of monazite imported from Australia, since late 1994, the ore used (bastnasite) is pretreated at the place of extraction (Bayun Oba, China and Mountain Pass, United States) before extraction of rare earths to La Rochelle.
Step 3 Separation of rare earths: again with solvent extraction units, lanthanum (at 99,995% purity) is extracted, and cerium (99.5%), the DIDYME (Nd-Pr alloy composed of Pr and 98% to 95% Nd) [note: the very names for Pr and Nd comes from ancient greek "twins" (dyme), illustrating the difficulties in separating them. Indeed, they were considered at first as only one element], samarium / europium (separated into 98% Sm and Eu 99.99%), the gadolinium / Terbium (separate then 99.99% Gd and Tb in 99.9%), and all other rare earths, yttrium is obtained, after extraction, 99.99%.
During the various extractions, many types of solvents are used: acid di (2-ethylhexyl) phosphate, tri (n-butyl) phosphate, quaternary ammonium salts, carboxylic acids ... In the factory of La Rochelle, more than 1 500 steps of mixer-settlers treatment are used.
Rare earths are separated delivered in the form of oxides or salts, the purity is, in general, expressed in mass compared to other rare earths, regardless of any other impurities present.
Step 4: Metals and especially neodymium, yttrium and terbium, are prepared by calciothermie to over 1 000 ° C, from the fluoride in the case of neodymium according to the reaction:
2NdF3 + 3 Ca ---> 2Nd + 3CaF2
These operations are metallurgical, Rhône-Poulenc, conducted in the United States, Phoenix (Arizona)
General info:Purification/extraction process is long and costly. Difficulties will increase with radioactive ore content, and decrease if the use can make fit of low purity alloys.
There is an obvious pro-Rhône Poulenc spin in this text, but I don't think it will affect the general information about extraction steps. A free fox in a free henhouse!
