Fabrication of Li2TiO3 spherical microparticles from TiCl4 by a classical, inorganic sol-gel route; characteristics and tritium release properties

摘要

Medium sized spherical particles of Li2TiO3 (with diameters below 100 mum) can be fabricated by a classical, inorganic sol-gel process, from commercially available TiCl4. Elaborated process consists of the following main steps: (1) dissolving of TiCl4 in concentrated aqueous HCl; (2) formation of sol emulsion in 2-ethylhexanol-1 containing the surfactant SPAN-80 (EH); (3) gelation of emulsion drops by extraction of water with partially dehydrated EH; (4) impregnation of gel to Li : Ti molar ratio (MR) = 2; (5) thermal treatment at 1200degreesC. This temperature can be significantly lowered (to 750degreesC) by chemical treatment of chloride precursors (gels or starting solution TiCl4) with aq. ammonia or better with nitric acid. Tritium release from sol-gel made Li2TiO3 micro-spheres were found very close to that observed for other traditional materials, however for the first sample process starts slightly earlier. (C) 2002 Kluwer Academic Publishers. [References: 9]