Effect of Al-containing precursors on ionothermal synthesis of aluminophosphate molecular sieve

Aluminophosphate molecular sieve AlPO4-11 was synthesized in the room temperature ionic liquid 1-ethyl-3-methylimidazolium bromide as both the solvent and template with different Al sources at ambient pressure. The effects of composition of incipient gels, crystallization time and crystallization temperature on synthesis of AlPO4-11 molecular sieve with different Al sources were investigated. The structure of A1PO4-11 molecular sieve was characterized by X-ray diffraction and scanning electron microscopy. The results indicated that the different properties of raw materials lead to the different mechanisms and rules on the ionothermal synthesis. When Al[OCH(CH3)2]3 was used as the Al source, the optimal ratio of P/Al in the incipient gels was 3/1, the crystallization was slow. When Al2O(CH3COO)4·4H2O was used as the Al source, the ratio of P/Al in the incipient gels was low (P/Al=1.5/1) and the crystallization was rapid.