Hydrothermal synthesis of pure AlPO_4-5 without fluoride medium: synthesis, characterization and application as a support

摘要

Hydrothermal synthesis of pure AIPO_4-5 crystals using various reaction gels is reported. The influence of synthesis conditions on the purity of the AlPO_4-5 has been studied by changing Al sources and factors affecting the pH of the starting gel. It was observed that the additive acid to adjust the gel pH value has strongly influenced both the crystallinity and purity of the resulting AIPO_4-5 crystals. The crystals were characterized by XRD, FT-IR, TGA, BET, SEM and TPD techniques. The resulting microporous AlPO_4-5 was used as an efficient support for a functional polymer to produce an efficient heterogeneous basic nanocomposite catalyst. The catalytic activity of this novel nanocomposite was tested for Knoevenagel reaction under solvent-free conditions at room temperature. The catalyst showed a considerable degree of reusability besides very good activity.