Print Email Facebook Twitter The adsorption mechanisms of organic micropollutants on high-silica zeolites causing S-shaped adsorption isotherms Title The adsorption mechanisms of organic micropollutants on high-silica zeolites causing S-shaped adsorption isotherms: An experimental and Monte Carlo simulation study Author Jiang, N. (TU Delft Sanitary Engineering) Erdös, M. (TU Delft Engineering Thermodynamics) Moultos, O. (TU Delft Engineering Thermodynamics) Shang, R. (TU Delft Sanitary Engineering) Vlugt, T.J.H. (TU Delft Engineering Thermodynamics) Heijman, Sebastiaan (TU Delft Sanitary Engineering) Rietveld, L.C. (TU Delft Sanitary Engineering) Date 2020 Abstract The adsorption of organic micropollutants (OMPs) on high-silica zeolites is characterized by adsorption isotherms with various shapes. The occurrence of an S-shaped adsorption isotherm indicates the lack of adsorption affinity for OMPs at low, environmentally relevant equilibrium concentrations. In this study, S-shaped isotherms were observed during batch experiments with 2,4,6-trichlorophenol (TCP) and FAU zeolites. This is the first time that an S-shaped isotherm is reported for the adsorption of OMPs on high-silica zeolites. Monte Carlo (MC) simulations in the grand-canonical ensemble were used to obtain a better understanding of the mechanism of the S-shaped adsorption isotherms. From the MC simulation results, it was observed that multiple TCP molecules were adsorbed in the supercages of the FAU zeolites. It was found that the π-π interactions between TCP molecules give rise to the adsorption of multiple TCP molecules per supercage, and thus causing an S-shaped adsorption isotherm. Simulations also revealed that water molecules were preferentially adsorbed in the supercages and sodalite cages of the FAU zeolites. FAU zeolites with a higher Al content adsorbed a higher amount of water molecules and a lower amount of TCP, and showed less pronounced S-shaped isotherms. Subject High-silica zeolitesMonte Carlo simulationOrganic micropollutantsS-shaped adsorption isotherms To reference this document use: http://resolver.tudelft.nl/uuid:fbe947e4-0fb1-4189-a663-11be9f303e51 DOI https://doi.org/10.1016/j.cej.2019.123968 ISSN 1385-8947 Source Chemical Engineering Journal, 389, 1-9 Part of collection Institutional Repository Document type journal article Rights © 2020 N. Jiang, M. Erdös, O. Moultos, R. Shang, T.J.H. Vlugt, Sebastiaan Heijman, L.C. Rietveld Files PDF 1_s2.0_S1385894719333832_main.pdf 1.36 MB Close viewer /islandora/object/uuid:fbe947e4-0fb1-4189-a663-11be9f303e51/datastream/OBJ/view