Synthesis of ZSM-5 zeolites using hexamethylene imine as a template: Effect of microwave aging

Zeolite ZSM-5 can be synthesized from gels containing hexamethylene imine (HMI) as an inexpensive template under adequate conditions. Microwave aging under suitable conditions is essential for the crystallization of ZSM-5 from gels containing HMI. Moreover, adequate reaction conditions (such as Al ₂O₃/SiO₂, HMI/SiO₂ and H ₂O/SiO₂ ratios, pHs, reaction times and so on) for ZSM-5 syntheses are also suggested. The obtained ZSM-5, after ion exchange to the proton form, can be applied in acid-catalyzed reactions because the acidity and surface area of the zeolite are similar to those of commercial ZSM-5 zeolite. For example, the H-ZSM-5 can be applied in the dehydration of bioalcohols such as ethanol and n-butanol into olefins or aromatics, quite similar to a commercial H-ZSM-5 zeolite.