SAPO-5分子筛酸性调变研究进展

Research progressin acid modulation of SAPO-5 zeolites

综述了SAPO-5分子筛的酸性调变方法,包括酸处理、盐处理、蒸汽处理、碳改性、金属改性以及构建多级孔等,其中金属改性和构建多级孔改性的方法研究较多。金属改性可以通过掺杂、浸渍、离子交换、微波处理和固态反应法将过渡金属阳离子引入到晶格中,部分或完全取代骨架元素来调变表面酸性,缺点是晶格阳离子被金属元素取代后容易形成晶格缺陷。构建多级孔包括微-微多级孔和微-介多级孔,该方法可以结合多种孔道优势并改变分子筛酸性达到多功能催化的目的。未来的发展趋势是将构建多级孔与金属改性相结合。

The acid modulation methods of SAPO-5 zeolites are reviewed, including treatments by acids, salts and steam, modifications by carbon and metals and hierarchical poreconstruction. Among them, the methods of metal modification and hierarchical mesoporeconstruction were studied widely. Metal modification can introduce transition metal cations？into the crystal lattice and partly or completely replace the skeleton elements to adjust the surface acidity by doping, impregnation, ion exchange, microwave treatment and solid state reaction method, but it has the disadvantage thatit is easy to form the lattice defect after the lattice cation is replaced by the metal element.？Hierarchical poreconstructions include micro-micro and micro-meso hierarchical pores, which can be used to combine various pore channels and change the acidity of the zeolites to achieve the purpose of the multi function catalysis. The development trend of the future is to combine the hierarchical poreconstruction withthemetal modification.