Computational Modeling and Advanced Synthesis Techniques for the Improved Design of ZSM-5 Zeolite Catalysts

ORAL

Abstract

Zeolites are the most widely used catalysts in industry. Active sites in zeolites are created by Al substitution of framework Si atoms in crystallographically different positions on the exterior or in the porous interior of zeolite crystals. This leads to heterogeneous chemical/kinetic behavior of various active sites, which can be employed to tune the properties of zeolites in catalytic processes. On the experimental side of this project, the shape selectivity of ZSM-5, an important zeolite catalyst in the petrochemical industry, is enhanced by manipulating its active site distribution. An advanced synthesis method was designed to passivate the external surface of ZSM-5 particles and suppress the reaction of bulky reactants over the exterior of the catalyst particles. The investigation of the impact of heterogeneous distribution of H-ZSM-5 active sites is continued through density functional theory (DFT) simulation, which reveals a large variation in the characteristics of 12 distinct active sites. The modeling of a test reaction indicates that pore confinement effects vary among different H-ZSM-5 active site locations, resulting in non-identical kinetic behavior through different extents of transition state stabilization. This heterogeneous performance not only causes different rates of reaction, but also impacts the dominant reaction mechanism at typical reaction conditions.

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Authors

  • Arian Ghorbanpour

    University of Houston

  • Jonathan Tan

    Duquesne University, Baker Hughes, Hampton University, Korea Research Institute of Standards and Science, Electronics and Telecommunications Research Institute, Texas Christian University, University of North Texas Health Science Center, Austin Peay State University, Virginia Military Institute, Pennsylvania State University, University of Virginia, Washington University, National Institute for Materials Science, Japan, Tokyo Metropolitan University, Japan, Univ of Kentucky, Argonne National Laboratory, Oak Ridge National Laboratory, Univ of Virginia, James Madison University, Department of Chemistry & Biochemistry, High Point University, Department of Chemistry, High Point University, Department of Physics, James Madison University, Department of Physics & Astronomy, Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA, Institute of Renewable Energy and Environment Technology, University of Bolton, Bolton, UK, Division of Materials Science and Engineering, Ames Laboratory, US Dept. of Energy, Ames, IA, Lehigh University, University of Pardubice, Universite de Rennes, Jan Dlugosz University, Translume, NSCL/FRIB, Duke University, University of Massachusetts - Amherst, University of St. Andrews, National Radio Astronomy Observatory, University of Florida, Yale University, None, Georgia College & State Univ, Georgia College & State University, National University of Sciences and Technology (NUST), Univ of Tennessee Space Inst, The University of Virginia, Chiang Mai University, DHA Suffa University, Faculty of Chemical Technology, University of Pardubice, Pardubice, Czech Republic, Department of Physics and Astronomy, Austin Peay State University, Clarksville, TN, United States, George Mason University, Northern Virginia Community College, Department of Physics, University of Virginia, Istanbul University, Georgia College and State University, University of Houston, Western Kentucky Univ, James Madison University, Virginia Polytechnic Institute and State University, Pontifica Universidad Catolica de Chile, Trent University, Univ of Arizona, Ohio State University, NRAO, University of Virginia/NRAO

  • Jonathan Tan

    Duquesne University, Baker Hughes, Hampton University, Korea Research Institute of Standards and Science, Electronics and Telecommunications Research Institute, Texas Christian University, University of North Texas Health Science Center, Austin Peay State University, Virginia Military Institute, Pennsylvania State University, University of Virginia, Washington University, National Institute for Materials Science, Japan, Tokyo Metropolitan University, Japan, Univ of Kentucky, Argonne National Laboratory, Oak Ridge National Laboratory, Univ of Virginia, James Madison University, Department of Chemistry & Biochemistry, High Point University, Department of Chemistry, High Point University, Department of Physics, James Madison University, Department of Physics & Astronomy, Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA, Institute of Renewable Energy and Environment Technology, University of Bolton, Bolton, UK, Division of Materials Science and Engineering, Ames Laboratory, US Dept. of Energy, Ames, IA, Lehigh University, University of Pardubice, Universite de Rennes, Jan Dlugosz University, Translume, NSCL/FRIB, Duke University, University of Massachusetts - Amherst, University of St. Andrews, National Radio Astronomy Observatory, University of Florida, Yale University, None, Georgia College & State Univ, Georgia College & State University, National University of Sciences and Technology (NUST), Univ of Tennessee Space Inst, The University of Virginia, Chiang Mai University, DHA Suffa University, Faculty of Chemical Technology, University of Pardubice, Pardubice, Czech Republic, Department of Physics and Astronomy, Austin Peay State University, Clarksville, TN, United States, George Mason University, Northern Virginia Community College, Department of Physics, University of Virginia, Istanbul University, Georgia College and State University, University of Houston, Western Kentucky Univ, James Madison University, Virginia Polytechnic Institute and State University, Pontifica Universidad Catolica de Chile, Trent University, Univ of Arizona, Ohio State University, NRAO, University of Virginia/NRAO