Phase composition and texture of Sr(La)Mn hexaaluminates

Hexaaluminates synthesized by precipitation and calcined at 700–1400°C have been characterized by atomic absorption spectroscopy, thermal analysis, X-ray powder diffraction, and adsorption methods. The heat treatment of the Mn-substituted and unsubstituted materials at 1100 and 1200°C yields a hexaaluminate phase. The specific surface area of the samples calcined at 1100°C is 20–49 m2/g. The texture of the samples calcined at 1000°C is characterized by a unimodal mesoporous pore size distribution with a mean pore diameter of 290 A.