Abstract
Atomistic scale models were developed and coupled with experimental investigation to deliver a functional understanding of catalytic activity and selectivity in the conversion of ethanol to 1,3-butadiene over Ag/ZrO2/SiO2. A detailed evaluation of the structural and electronic properties of the resultant catalyst models led to the identification of critical active sites of the catalyst. More importantly, the extent of Ag dispersion on the SiO2 support and relative proximity to ZrO2 were found to vary with the oxidation state of Ag and local coordination environment (Ag-OSiO2), allowing for critical control of ethanol conversion towards butadiene or ethylene. Simulations revealed that less dispersed or clustered Ag contain predominantly Ag0 charge state and promote conversion of ethanol to ethylene. The well-dispersed Ag/ZrO2/SiO2 catalyst instead contain a larger fraction of cationic Agδ+ and predominantly promote ethanol dehydrogenation and subsequent production of butadiene. The theoretical insights drawn were validated and confirmed experimentally using TEM, XRD and reactivity measurements demonstrating the effect of Ag dispersion on the selectivity of ethanol conversion.
| Original language | English |
|---|---|
| Pages (from-to) | 30-38 |
| Number of pages | 9 |
| Journal | Journal of Catalysis |
| Volume | 386 |
| DOIs | |
| State | Published - Jun 2020 |
Funding
The authors gratefully acknowledge funding for this research, provided by the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies Office (BETO), at the Pacific Northwest National Laboratory (PNNL), and in collaboration with the Chemical Catalysis for Bioenergy Consortium (ChemCatBio), a member of the Energy Materials Network (EMN). PNNL is a multi-program national laboratory operated for DOE by Battelle Memorial Institute. Use of catalyst characterization equipment and computational resources was provided by a user proposal at the William R. Wiley Environmental Molecular Sciences Laboratory, which is a national scientific user facility sponsored by the DOE Office of Biological and Environmental Research and located at PNNL in Richland, WA. SAA preformed part of calculations and manuscript preparation of this work under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. The authors gratefully acknowledge funding for this research, provided by the U.S. Department of Energy (DOE) , Office of Energy Efficiency and Renewable Energy (EERE) , Bioenergy Technologies Office (BETO) , at the Pacific Northwest National Laboratory (PNNL) , and in collaboration with the Chemical Catalysis for Bioenergy Consortium (ChemCatBio) , a member of the Energy Materials Network (EMN) . PNNL is a multi-program national laboratory operated for DOE by Battelle Memorial Institute. Use of catalyst characterization equipment and computational resources was provided by a user proposal at the William R. Wiley Environmental Molecular Sciences Laboratory, which is a national scientific user facility sponsored by the DOE Office of Biological and Environmental Research and located at PNNL in Richland, WA. SAA preformed part of calculations and manuscript preparation of this work under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344 .
Keywords
- Ab initio molecular dynamics (AIMD)
- Ag
- Biomass
- Butadiene
- Density functional theory (DFT)
- Ethanol
- Ethanol upgrading
- Heterogeneous catalysis
- Packed bed
- SiO
- Thermal catalysis
- ZrO