Synthesis Of Aluminophosphate Zeolites In Imidazolium Based Ionic Liquids

Synthesis of zeolites in ionic liquids,termed as "ionthermal synthesis",is a very promising approach for preparing porous materials,and has received much attention recently. In this thesis,various conditions were investigated in the synthesis of aluminophosphate zeolites in imidazolium based ionic liquids.XRD,³¹p MAS NMR,²⁷Al MAS NMR,¹³C MAS NMR and SEM/TEM were used to characterize the structure of the resultant zeolites.It is found that crystallization temperature and time,the type and amount of ionic liquids,P/Al ratio,the amount of HF and organic amine have great influence on the product phases. Different zeolite phases with AEL,AFI or LTA structure can be obtained depending on the synthesis conditions.The role of organic amine in the ionthermal synthesis has also been studied.Multinuclear NMR results confirm the intermolecular interaction between morpholine and ionic liquids,which may result in the co-templating effect of organic amine and ionic liquids in directing different zeolite phases.Moreover,the nanosized AFI zeolites with average particle size of 60 nm were also successfully prepared.In our synthesis system, the nanosized zeolites can only be obtained during the phase transformation from AFI structure to AEL structure.