Original paper(Vol.48 No.6 pp.571)

Selective synthesis of a crystalline aluminum orthophosphate in organic solvent

Sakamoto Kiyoko; Yamaguchi Shunro; Nakahira Atsushi

Abstract:Crystalline aluminum orthophosphate AlPO 4 has various polymorphic forms. However, it is difficult to prepare a pure single phase AlPO 4. In order to synthesize a single phase of AlPO 4, we have undertaken the dehydration of aluminum orthophosphate dihydrate AlPO4 center dot 2H2O (metavariscite) in organic solvent. The crystalline phases of obtained products were identified by X ray diffraction method and measurement of MAS NMR super 3 super 1P and super 2 super 7Al. A crystalline AlPO 4 (berlinite, tridymite form, cristobalite form, or A form) was selectively synthesized by controlling the amount of H3PO 4 and sort of organic solvent (1 butanol and isobutyl methyl ketone).

Key Words:crystalline aluminum orthophosphate, metavarriscite, berlinite, tridymite-form, cristobalite-form, organic solvent