Microwave synthesis of AFI-type aluminophosphate molecular sieve under solvent-free conditions

Abstract AlPO 4 -5 aluminophosphate molecular sieve with AFI topology has been successfully synthesized by microwave irradiation under solvent-free conditions. The key influential factors controlling the crystallization of AFI structure were thoroughly investigated. The optimum synthetic conditions of this material are as follows: the initial composition is 1.0Al 2 O 3 : 3.0P 2 O 5 : 2.0HF: 8.0TEABr(tetraethylammonium bromide): 125C, aluminum isopropoxide is the best aluminum source, and activated carbon needs to be pretreated before used as the reaction medium and hard template. The resultant AlPO 4 -5 molecular sieves were characterized by X-ray diffraction (XRD), N 2 physisorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results reveal that the obtained samples exhibit hierarchically porous characteristic.