Mesoporous ZSM-5 loaded with amino acids: does secondary mesoporosity affect sorption capacity and thermal regeneration?

Hierarchically Organized ZSM-5 is built on a multilevel pore network, which makes it a promising adsorbent for biochemical molecules, such as amino acids. Despite their primary role in the enhancement of catalyst effectiveness, no structural investigation about amino acids adsorption/desorption processes on mesoporous ZSM-5 have ever been performed. In this work, the in situ structural characterization of mesoporous ZSM-5 after adsorption of l-lysine (C6H14N2O2) and leucine (C6H13NO2), as single compounds from aqueous solution is presented for the first time. All the results obtained through in situ Synchrotron X-ray powder diffraction (MCX Beamline, Elettra) allowed to determine mesoporous ZSM-5 sorption capacity as well as thermal regenerability, which are fundamental information for the development of superior zeolite biocatalysts.