Synthesis and adsorption properties of zeolite-like aluminophosphates

Zeolite-like aluminophosphates AlPO4-5, AlPO4-18, and AlPO4-20, were prepared in conditions which differ from those described in the literature. The adsorption isotherms of H2O, CH3OH, n-C4H9OH, and i-C4H49OH at 18°C and Ar at −196°C were investigated. The observed molecular-sieve effect is in agreement with the concepts on the structure of these aluminophosphates. An unusual shape of the water adsorption isotherms was observed. Similarities were observed in the isobaric absorption of water molecules by crystal hydrates and the zeolite-like aluminophosphates.