Key words: aluminum oxide, lanthanum oxide, water fluid, hydration, lanthanum aluminate, morphology
The effect of the synthesis method on the formation of the structure and composition of materials composed of porous alumina supported lanthanum oxide, has been studied. The effect of the morphology of porous aluminum oxide (α-modification) on the formation of various compounds (oxide La2O3 and aluminates LaAlO3 and La10Al4O21) during thermal treatment of a support impregnated with a solution of lanthanum nitrate is shown. It was found that when systems are treated in a water fluid, the processes of structuring and phase formation proceed at a much lower temperature and more intensively than under thermal action, which is due to the high mobility of structural elements in a hydrated state. It is shown that the formation of LaAlO3 aluminate is limited by the hydration of the initial aluminum oxide, which proceeds more intensively in the case of its γ-modification. Varying the sequence and conditions of the stages of treatment in a water fluid and thermal action makes it possible to obtain composites of various morphologies and containing various single and complex oxide compounds and phases.
doi:10.34984/SCFTP.2021.16.3.008