Preparation and Characterization of the Lithium Metatitanate Ceramics by Solution-Combustion Method for Indian LLCB TBM

In fusion DEMO reactors, the blanket requires lithium-containing ceramics as the tritium breeder material. Lithium metatitanate (Li₂TiO₃) is being considered as a promising tritium breeding material for thermonuclear fusion reactors because of its reasonable lithium atom density, prominent tritium release rate at low temperatures, low activation characteristics, low thermal expansion coefficient, high thermal conductivity, etc. Li₂TiO₃ will be used in the Indian Lead-Lithium–Cooled Ceramic Breeder concept to be tested in ITER. Li₂TiO₃ powder has been synthesized by the solution-combustion technique using a less expensive precursor of titanium, i.e., titanium dioxide (TiO₂), at Institute for Plasma Research. Titanium oxynitrate [TiO(NO₃)₂] and lithium carbonate (Li₂CO₃) with citric acid fuel are used as the raw materials. The combustion reaction was carried out at citrate-to-metal ratios of 0.8 to 1.5, as well as for various pH values ranging from 1 to 5. Citric acid was used as a fuel material for the reaction. Calcination of the powder was carried out at 600°C. The powders were characterized for phase purity, grain size, and surface area using X-ray diffraction, scanning electron microscopy, and a Brunauer-Emmett-Teller surface area analyzer. Finally, Li₂TiO₃ pebbles were prepared by extrusion followed by spheronization with a diameter range from 1 to 1.5 mm. The details of the powder systemization, pebble formation, and their various characterizations are discussed in this paper.