(97f) Confinement Effects on Solvation Thermodynamics of Biomass Adsorbates in Zeolites

Biomass is an abundant resource that can be converted into fuels and commodities using zeolite catalysts. Zeolites are microporous aluminosilicate materials that exhibit high reaction selectivities due to having different pore sizes, which promote formation of certain products depending on their size and shape. This confinement effect is amplified in aqueous phase, since the pores additionally influence the solvent molecules. Specifically, the pore structure constrains the arrangement and density of water molecules, and this can have a significant impact on catalytic chemistry. A more detailed understanding of the relationship between the properties of the zeolite catalyst and the adsorbate on solvation phenomena is thus key to design of zeolites for aqueous phase catalysis. We are specifically interested on the influence of confinement on the free energies of solvation of interfacial species. Hence, herein, we compute the free energies of solvation of biomass intermediates adsorbed in zeolite pores under explicit water solvent using the method of multiscale sampling (MSS), which uses a combination of density functional theory and classical molecular dynamics to compute free energies of solvation of interfacial species. We specifically investigate how zeolite hydrophilicity, zeolite pore geometry, adsorbate geometry, and adsorbate polarity influence the enthalpies and entropies of solvation. Influence of these properties on free energies of solvation of interfacial species and hence on catalytic chemistry will be discussed.