AlPO-91: A 16-Layer ABC-6 Aluminophosphate with Five Distinct Cage Types

The properties and pore structure of microporous materials are dictated by the composite building units that link together to form the crystal structure. Cage-based building units predominate in the ABC-6 family of molecular sieves, and of all the known ABC-6 materials, none are observed to have more than four different cage types in their framework structure. We present here a new aluminophosphate material, AlPO-91, which has five distinct cage types present in its framework. AlPO-91 was discovered through modifications to the synthesis of a related and previously reported material, AlPO-78. AlPO-91 and AlPO78 represent an interesting subclass of ABC-6 materials in which a number of d6r and s6r subunits are equal. This property has important implications for the porosity and potential applications of AlPO-91 and related materials.