I want to synthesis ZSM-5 with pure Bronsted and Pure Lewis acid sites separately. Is it possible to synthesis these two catalysts with same metal ( i.e. Al or any other) via incorporation in their framework during hydrothermal treatment. Can I synthesis these catalysts by Impregnation/Ion-exchange with particular metal to create desired type of acidity. In literature I found Sn, Ti, Zr, Hf have been used for Lewis acid sites, which metal I can use to generate pure Bronsted acid site (without LAS)? Please recommend some literature and share your kind experience.