T h e L A N T H A N I D E S in
BETTER WAYS OF PUTTING CHEMICAL PIECES TOGETHER
V
Lanthanide-exchanged zeolites — with outstanding (hydro)thermal stability — are the heart of current ^3dBC^UiÎLBL·Σi^iLlfe5i6^Lâf3i r c o n v e r t ' ing crude oil fractions to gasoline, the largest volume use of any catalyst system.
Acetylene can be polymerized by lanthanide alkoxide/aluminum alkyl systems to form polyacetylene of high cis content; subsequent doping produces ΙΜιΜΙΜΙΙιΙιΙΙΐΒΓΠΠΕΙ — of interest in battery development.
Textile fibers, cellulosics and starches can be modified by the graft copolymerization onto them of PS, PMMA, PVAc and such — initiated with free radicals produced by Ce(IV) systems. Special properties, such as water absorbency can be imparted.
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Stereospecif ic polymerization of dienes with lanthanide-based catalysts can produce high stereo-regularity, e.g. butadiene is converted 97% into cis-1,4-polymer. Improved routes to elastomers and thermoplastics are possible.
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Cerium in automobilel^M^IIJ^illlTO'HTldoes more than stabilize the gamma-alumina support against high-temperature degradation. It also aids in oxidizing the pollutants under fuelrich air-poor conditions; Ce0 2 can "donate oxygen" through formation of non-stoichiometric oxide.
Aldehydes and ketones treated with (stoichiometric) organo-Ce and -Sm reagents will form addition products, differing from those made by classic organo-metallics, as intermediates for pharmaceuticals and specialties
Intermetallic compounds of the lanthanides with other elements offer catalytic variety t0
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chemicals; the interplay between adsorbed H2, reactive Η, and other intermediates is a factor.
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MOLYCORP
THE LANTHANIDE MINERAL is bastnasite, 12% of the ore we mine at Mtn. Pass, California (supplying over half of free world need). It contains all nine of the principal lanthanides, in proportions much as in the exploding pie chart at the left. Forty million tons of ore are in the deposit — ample for decades to come. OR CIRCLE 36 ON
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Yield and efficiency in photovoltaic devices for utilizinafcTnT?prnrf7TObv catalytically splitting water for electricity and hydrogen, can be improved with Ce or Eu redox systems or with lanthanide-containing perovskite-based semi conducting anodes.
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Sulfur dioxide is removed from gas streams by catalysts containing lanthanide oxides; furthermore lanthanum oxysulfide is active for coreduction of S0 2 with COS and CO. •ΗΤΠΊrrnΜΠ^ΤΤΡΗΤΜΪΗΪΤΓΤΝΪffTiTTIΓΜ can be thus' achieved. ^ ^ ^ ^ ^ ^
Abstracts and data on these classes of Ln catalysis ate ^ Mailable. Just ask ^-^
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MOLYCORP, INC. 709 Westchester Avenue White Plains, NY 10604 914/997-8880 * TWX 710/568-0305
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My concern with catalysis is
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