Direct synthesis of mesoporous Fe-MFI zeolite

摘要

The direct synthesis of mesoporous Fe-MFI zeolite via a novel route is reported. A whole range of as-synthesised Fe-MFI zeolites with varying iron (0.075 – 0.6 wt%) and aluminium (0 – 1.1 wt%) concentrations contain mesopores. The main difference of the new method with respect to conventional synthesis of Fe-MFI zeolites is that instead of adding iron salts (eg Fe(NO3)3) to the solution gel, a synthesis gel starting from metallic iron foil dissolved in nitric acid is used. A broad mesopore-size distribution is observed with transmission electron microscopy for all as-synthesised Fe-MFI zeolite samples. The mesopores are retained after calcination as well as after subsequent mild steaming.