Formation of lanthanum aluminate during coprecipitation of carbonate and hydroxide compounds of lanthanum and aluminium

Chemical interaction of lanthanum and aluminium salts upon their combined precipitation with ammonium carbonate and ammonia has been studied by the methods of chemical, thermal, microscopic, X-ray phase, and electron diffraction analyses. It has been established that interaction of carbonate (pH 7.5-8.5) and hydroxide (pH 8.5-9) compounds of lanthanum and aluminium at room temperature in an aqueous medium yields lanthanum aluminate which crystallizes in a cubic structure of the perovskite type (a=3.8 A). The degree of interaction of lanthanum and aluminium salts increases with ageing of precipitates