Combustion Synthesis of Gamma-Lithium Aluminate

Lithium aluminate (LiAlO2) powder, which can be used as a tritium breeding material for fusion reactors due to its thermal and mechanical properties, was prepared by fuel-assisted combustion synthesis from lithium nitrate and aluminium nitrate. Various fuels such as citric acid, urea, and mixed fuels of citric acid and urea were tested. A mixed fuel of citric acid and urea was found to produce gamma LiAlO2 powder with good crystallinity. A proper mixing composition of reactants was found to be 5/18M of citric acid and 5/2M of urea for 1M of each nitrate. The synthesised powder had an average particle size of 0.14 micron and a specific surface area of 16.4 m2/g. The activation energy of the combustion synthesis was found to be 54.4 plus or minus 6.4 kJ/mole. 23 refs.