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New generations of crystalline microporous molecular sieve oxides have been discovered based on the novel aluminophosphate family by incorporating one or more of an additional thirteen elements from the Periodic Table into the AIPO4 framework. Elements incorporated include Li, Be, B, Mg, Si, Ga, Ge, As, Ti, Hn, Fe, Co, and Zn, spanning monovalent through pentavalent framework cationic species. The new materials comprise more than two dozen structures and two hundred compositions, including multi-element frameworks containing combinations of up to six framework cations. Pore sizes range from 0.3nm to 0.8nm encompassing small, intermediate and large pore structures. The new molecular sieves are synthesized by hydrothermal crystallization of reactive aluminophosphate gels containing the additional framework elements and an organic template. Proof of framework incorportion includes the formation of novel structures, the enhancement of catalytic activity, elemental analysis, and various spectroscopic evidence. The Bronsted acidity observed ranges from weakly to strongly acidic. This landmark discovery of new generations of molecular sieve materials represents a remarkable diversity in crystal structure and crystal chemistry, and offers a nearly unlimited number of design parameters to tailor adsorptive and catalytic properties. |
