The How and Why for Reusing Rare Earth Magnets Gwen Spicer Gwen Spicer Spicer Art Conservation, LLC www.spicerart.com gwen@spicerart.com Inside the Conservators Studio @ blogspot
Rare Earths - Lanthanide! Commonly found in the Earth s crust and are not rare! Composed of the group of elements located at the lower region of the periodic table! The Lanthanides numbers 57 To 71 on the periodic table! First found in the late nineteenth century, but took time to understand how to separate the various elements! All are susceptible to corrosion
(Gschneider 2015)
Light group Heavy group (Zepf 2013)
Lanthanum (57)! Electron Filling Order! Lanthanides fill the 4f valance shell (Gray 2011)
Process developments needed for separation! Repeat precipitation or crystallization! 1839, Solvent distraction (Heating and dissolving in nitric acid)! 1879, Optical-flame spectroscopy! 1909, X-ray Spectra! 1940s (Manhattan Project) Chemical ion exchange
(Zepf 2013)
(Zepf 2013)
Silent Revolution! (Livingston 1996)! Various uses of magnets in automobiles for which rare earths are used.
Ear Buds
Green Technology - Toyota Prius! 30 pounds of rare earths in each one! In the motor is 1 kilogram (2.2 pounds) of Neodymium! In each battery is 10 to 15 Kg (22-33 lbs) of lanthanum! The car is described as the biggest user of REs of any object in the world! Reached 4.8 Million cumulative sales by Sept. 2014 (67.7% of hybrids sold worldwide).
World Production & Trade! 1880s Brazil s Eastern Coast! 1948 Brazil and India dominated supply! 1950s South Africa! 1960s 80s US, Mountain Pass, CA! 1990s US domestically supplied its own RE needs! 2010 China, Inner Mongolia, 95% of the world wide supply.! 2011 China announced 40 % reduction of mining! 2012 China, continues reduction, resulting increase in costs temporally
(Humphries 2013)
Open Pit Mining! Mountain Pass, California! Russia
Bastnasite Ore (7% REO) Crushing Grinding Classification Steam Soda Ash Fluosilicate Steam Conditioner 1 Conditioner 2 Steam Steam Steam! REE mineral processing flow chart Conditioner 6 Rougher Flotation Tall Oil C-30 Cleaner Flotation 1 Conditioner 5 Conditioner 4 Cleaner Flotation 2, 3, 4 Ammonium Lignin Sulfonate Thickener Drum Filter Conditioner 3! Mountain Pass Mine! Bastnasite ore Tailings (1 to 2% REO) Ce Carbonate (90% CeO 2 ) Scavenger Flotation Regrind Rotary Kiln Dryer Bastnasite Concentrate (60% REO) Redox Separation Ce Concentrate (57% CeO 2 ) Thickener and Filter Oxidizing Roast Acid Leach HCl Filter SX Mixers Bastnasite Concentrate (85% REO) SX Loading Mixer-Settlers Bastnasite Concentrate (70% REO) SX Stripping Mixer-Settlers Precipitation Filter Calcination Nitrification HNO 3 Eu Redox Separation Nd Oxide La(NO 3 ) 3 Nd Pr SX Separation La Nd Pr SX Separation Sm Gd SX Separation Eu Purification Precipitation Filter Calcination Acid Treatment La Chloride HCl Precipitation Filter Calcination Precipitation Filter Calcination Precipitation Filter Calcination Pr Oxide Gd Oxide Sm Oxide Eu Oxide
Baotou, Inner Mongolia, China Bayon Obo Mine Satellites images
RE Metal Extraction! Open pit mining! Chemically treated using acid and alkali solutions! Solvent extraction or ion exchange! REEs are found with a mixture of radioactive elements Library of Congress
Care and handling of Nd-Fe-Br Magnets RE magnet sensitivities! Hest! Mechanical Shock! Do not use hot melt glue! Limit shock and snapping together! Use separators or embed into other materials! Moisture! Protect applied coating
Storage! Use small boxes! Cushion sides of boxes! Place spacers between each magnet! Use contact lens cases! Store in another location from ferrite magnets and other electronic equipment.
Cross-section view 2-ply mat board strips Hollytex or Mat board Magnets (Holbrow & Taira, 2011). Length view Fabric covering for internal support Needle-punch batting or carved Ethafoam Fender washer embedded into the support board that creates the footprint of the artifact base. Artifact with internal cavity (Carrel et al., 2005; Spicer, 2013). Display fabric Volara, thickness same as the embedded magnet Display deck made of DiBond
Thank you Gwen Spicer Spicer Art Conservation, LLC 518/ 765-2142 www.spicerart.com gwen@spicerart.com Inside the Conservators Studio @ blogspot