Adsorption of Polyols and Furfurals in All-Silica Zeolites

Polyols and furfurals are important commodity compounds that can be produced through biomass conversion. To increase the efficiency and lower the energy cost of the separation of these molecules from reactor effluents, adsorptive separation using nanoporous materials has been proposed as a promising technique. In order to better understand the capacity and the selectivity of all-silica zeolites to polyols and furfurals, configurational-bias Monte Carlo simulations in the Gibbs ensemble were performed to compute adsorption isotherms from solution phases. The TraPPE force field is extended to furfural and its derivatives and intramolecular potentials are determined for some polyols; good agreement with experimental liquid density and vapor pressure data is found for the unary vapor-liquid equilibria of these compounds.  The trends in the adsorption isotherms, the free energies of transfer, and selectivities of several selected polyol and furfural molecules are explained in terms of hydrogen-bond speciation and confinement effects in zeolite structures.