Page 167 - CW E-Magazine (5-8-2025)
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Special Report                                                                 Special Report



 The fi rst use that comes to mind for   An  unintended  consequence  of  ral gas or biogas; however the quality   the traditional electrode of yttria-stabi-  Regional trends  Sc O  producers, and most of the pro-
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 these alloys is aerospace, as it makes  these traits is that it could reduce basic  requirements  for  inputs  are  stringent.   lized zirconia (YSZ). Other advantages   duction  is from acid  wastes  of  TiO
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 for lighter and stronger structures. The  aluminium consumption.  SOFCs operate at high temperatures up   of SSZ use are:  China  industry.
 MIG-29 aircraft, made in Russia, sup-  to 900°C.    Improved ionic  conductivity: Add-  China is the world’s largest producer
 posedly uses Al-scandium alloy struc-  Sold Oxide Fuel Cells (SOFCs)  ing scandium oxide (Sc O ) helps  of scandium, but exact statistics are   Bayan Obo is the world’s largest
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 tures. In the passenger aircraft segment,   SOFCs are high effi  ciency station-  When Scandia-Stabilized-Zirconia   boost conductivity, improving the  diffi  cult to get as under HS classifi ca-  known  REE  deposit.  The  fl uorspar
 Airbus  introduced Al-Mg-Sc  alloys.  ary fuels cells with 80-85% (even 90%)  (SSZ) is used as the  solid electrolyte   fuel cell’s performance.  tion rare earth metals and scandium are  content of  the  ores  also makes  it  the
 The 45% weight reduction for its A320  effi  ciency with a modular capacity up  layer of the SOFC, it allows longer life     Increased durability: Sc O  helps  clubbed together and scandium may be  world’s  largest  fl uorspar  deposit.
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 planes reduces its fuel consumption  to 250-kW. They can operate with natu-  and higher power density compared to   stabilize  parts of the fuel  cell,  a very small percentage of the total.  Reserves are estimated at more than
 and lowers its  carbon footprint.   making them more resistant to heat   40-mt of REE minerals grading at 3-5.4%
 Table 2: Applications of Sc O  in SOFCs  and mechanical stress.  The vast majority  of Sc O  pro-  REE (70% of world’s known REE
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 There is also very large potential   Application  Benefi ts    Lower operating temperature: Scan-  duced in China comes from the waste  reserves); 1 million tons of neodymium
 use  for  Al-Sc  alloys in the auto-  Stationary power generation  Sc O -enhanced SOFCs  are  perfect for   dium provides the highest known  acid discharged during the production  oxide  (Nd O ) and 470-mt of iron.
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 motive  industry if the cost can be   stationary power generation, such as power   rate of transport of oxygen, and  of TiO  by the sulphuric acid process.  The  quantity  of  REE  deposits  mined
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 brought down.   plants, backup systems, and distributed   this permits the SOFC to operate at  For every tonne of  TiO  produced,  is not clear, but  there  are  two  large
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 energy. Their high effi  ciency and durability   temperatures  around 700°C, much  about  8-10 tonnes of waste  acid  con-  mines. Various ores in the Bayan Obo
 Scandium is also used in manu-  make them a reliable source of clean energy,   lower than the roughly 1000°C of  taining  10-25 mg/l Sc2O  is released  deposit have  Sc O  contents between
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 facture of  premium tennis rackets,   especially in remote areas or where a steady   conventional yttrium-doped SOFCs.  during the hydrolysis process.   40-169 ppm. In the REE ore tailing,
 baseball bats, sports cycles, tent poles   power supply is critical.  This lower operating  tempera-  the Sc O  content reaches 250-ppm,
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 and mountain climbing gear. Smith &  Transportation  Sc O -enhanced SOFCs can power vehicles   ture makes the system much more   With the wide application of TiO ,  therefore it is expected it should be a
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 Wesson revolvers are a faster draw as   where long-range and low emissions are   mechanically robust with less wear  increasing  amount of waste acid con-  major producer.
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 they have become lighter with use of   essential (e.g., trucks, ships, and even planes).   on the materials, a longer lifespan,  taining  scandium will be discharged
 Al-Sc alloys. Some of the other uses   Their ability to use diff erent fuels makes them   and reduced cost of insulation and  during the production of TiO . There-  Hunan Oriental  Scandium extracts
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 of Al-Sc alloys are high-performance,   fl exible for various transport needs.  cooling.  fore, TiO   waste  acid  is  a  signifi cant  scandium  from waste acid  of  TiO
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 lightweight mobility devices –  such    raw material for recovering Sc O .  plants. The company’s products include
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 as wheelchairs,  walkers, scooters,   Combined heat and power (CHP)  SOFCs generate electricity and use leftover   The  future of Sc O  in  SOFCs is   Sc O  and scandium metal.  It has a
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 crutches, canes, and prosthetic and or-  systems  heat for heating, boosting overall effi  ciency   promising. As the need for clean energy   China  has TiO   capacity  of 7-mtpa,  Sc O  production line with a capacity
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 thotic device – that can enable people   to about  85%. Sc O  improves  the  perfor-  grows, so will the demand for effi  cient  of which about 12-13% is via the chloride  of more than 10-tpa. The oxide is used
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 with physical disabilities participate in   mance and durability of these systems, mak-  and reliable fuel cells. Ongoing re-  route, and the rest by the sulphate route.  in the preparation of Al-Sc master alloy
 sports and other physical activities are   ing them more attractive  for homes, busi-  search aims to enhance Sc O ’s proper-  and the development and production
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 also made from Al-Sc alloys.  nesses, and factories.  ties,  making  it  even  more  eff ective   China is known to have a dozen  of Al-Sc alloys for civilian use. It has
 Table 1: Properties and the benefi ts of Al-Sc alloys  in fuel cells.  Advances in production   Table 3: Sc O  producers in China
 Property  Benefi t  methods may also  help reduce  costs,   Company  2  3                 Scandium source
 Increased strength to weight ratio  Overall weight may reduce by 10-15%.  making Sc O  more accessible.  Bayan Obo Deposit (REE plant and recovery of Sc O )  REE
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 Increased fuel effi  ciency  Reduction in fuel consumption and consequently emissions.  Bloom Energy (USA) has commer-  Hunan Oriental Scandium Co. Ltd. (TiO ) route  2  3  TiO  waste acid
 Enhanced weldability and durability  Typically, high-strength aluminium alloys suff er from poor weldability, limit-  cialised  use of Sc O  in SOFCs  and   2  2
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 ing its use. Components made from Al-Sc alloys can be welded without losing   appears to be the biggest scandium   Taojiang Ruilong Metals New Materials Ltd.  TiO  waste acid
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 strength at the weld joints, maintaining durability and longevity in structural   consumer globally.  Guangxi Maoxin Technology Co., Ltd.  TiO  waste acid
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 applications.                           Jiaozuo Rongjia Scandium Industry Science & Technology  TiO  waste acid
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 Improved high-temperature performance  Al-Sc alloys remain  stronger and more  stable  at  higher  temperatures  than   Other applications  Co., Ltd.
 conventional aluminium alloys, making it ideal for use in aerospace and auto-  Scandium-based lasers have unique   MCC Ramu New Energy Technology Co., Ltd.  Nickel recovery
 motive components, where materials are subjected to extreme heat.  This   properties:  Huizhou Top Metal Material Co., Ltd.  TiO  waste acid
 makes them especially useful in engines, exhaust systems, and other high-heat     Erbium-chromium: yttrium scandium-  2
 applications.  gallium-garnet  (Er,  Cr:  YSGG)   Hunan Jinkun New Material Co., Ltd.    REE
          lasers are used in dentistry.
 Increased corrosion resistance  Al-Sc alloys off er excellent resistance to corrosion, including pitting and stress     Gadolinium scandium-gallium gar-  Ganzhou  Wanfeng  Advanced Material  Technology Co.,  REE
 corrosion cracking, particularly in harsh environments such as marine with   net (GSGG) lasers have been   Ltd.
 exposure to salt water.  extensively studied in strategic   Hunan Kunwell Advanced Materla Co. Ltd.   TiO  waste acid
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 Enhanced formability  Can be easily shaped into complex structures without compromising mechanical   defence applications (laser defence   Henan Rongija Scandium Vanadium Technology Co., Ltd. TiO  waste acid
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 properties. There is improved toughness and enhanced fatigue resistance.  systems).  Hunan Oriental Scandium New Material Co., Ltd.  TiO  waste acid
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 166  Chemical Weekly  August 5, 2025  Chemical Weekly  August 5, 2025                                 167
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