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以二异丙胺为模板剂,利用微波辐射法合成了AlPO4-11和SAPO4-11分子筛,考察了合成压力、HF用量对合成AlPO4-11分子筛的影响;利用X射线衍射和扫描电子显微镜对所合成分子筛的结晶度及晶体形貌进行了表征。实验结果表明,利用微波技术合成的具有AEL晶体结构的AlPO4-11和SAPO4-11分子筛结晶度高、晶粒均匀(为长约5μm的棒状晶体)。通过考察晶化时间对合成产物的影响发现,微波合成的AlPO4-11分子筛是由六方晶系的正磷酸铝发生晶相转化而来的。利用X射线能谱对合成的SAPO4-11分子筛表面硅原子的含量进行了测定,并结合吡啶吸附傅里叶变换红外光谱表征结果证实,SAPO4-11分子筛具有B酸和L酸两种酸性位,但由于合成产物表面硅原子含量较少,因此酸性位也较少。
AlPO4-11 and SAPO4-11 zeolites were synthesized by microwave irradiation using diisopropylamine as template. The effects of synthesis pressure and amount of HF on synthesis of AlPO4-11 zeolite were investigated. XRD and SEM were used to characterize the synthesized Molecular sieve crystallinity and crystal morphology were characterized. The experimental results show that AlPO4-11 and SAPO4-11 with AEL crystal structure synthesized by microwave technology have high crystallinity and uniform grain size (about 5μm in length). By examining the influence of crystallization time on the synthesized product, it was found that the microwave-synthesized AlPO4-11 molecular sieve was transformed by the crystal phase of hexagonal aluminum orthophosphate. The content of silicon atom on the surface of synthesized SAPO4-11 zeolite was determined by X-ray energy dispersive spectroscopy. Combined with the results of pyridine adsorption Fourier transform infrared spectroscopy, it was confirmed that SAPO4-11 zeolite possesses two acidic sites of B acid and L acid, However, due to the synthesis of the surface of the silicon content is less, so less acidic position.