1
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Sun B, Wang GC. Investigation of the oxygen coverage effect on the direct epoxidation of propylene over copper through DFT calculations. Phys Chem Chem Phys 2023; 25:30612-30626. [PMID: 37933192 DOI: 10.1039/d3cp04362b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The direct epoxidation of propylene is one of the most important selective oxidation reactions in industry. The development of high-performance copper-based catalysts is the key to the selective oxidation technology and scientific research of propylene. The mechanism of propylene's partial oxidation catalyzed by Cu(111) under different oxygen coverage conditions was studied using density functional theory calculations and microkinetic modeling. We report here in detail two parallel reaction pathways: dehydrogenation and epoxidation. The transition states and energy distributions of the intermediates and products were calculated. The present results showed that propylene oxide (PO) selectivity was high under low oxygen coverage, and increasing the oxygen coverage would decrease the PO selectivity but increase the PO activity, and there was an inverse relationship between PO selectivity and activity. Increasing oxygen coverage would reduce the energy barrier for the C-O bond formation of C3H5O due to the weaker adsorption strength of C3H5, thus decreasing the PO formation selectivity. On the other hand, increasing oxygen coverage would reduce the energy barrier for the possible reaction steps of propylene epoxidation in general, and thus increasing the catalytic activity. It might be proposed that the active site for propylene epoxidation is the metallic copper or partially oxidized copper in terms of the change of PO formation selectivity with oxygen coverage.
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Affiliation(s)
- Ben Sun
- Frontiers Science Center for New Organic Matter, Tianjin key Lab and Molecule-based Material Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
| | - Gui-Chang Wang
- Frontiers Science Center for New Organic Matter, Tianjin key Lab and Molecule-based Material Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.
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2
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Performance, Reaction Pathway, and Pretreatment of Au Catalyst Precursor in H2/O2 Atmosphere for the Epoxidation of Propylene. Catalysts 2022. [DOI: 10.3390/catal12050540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Gas-phase epoxidation of propylene in the copresence of H2 and O2 was performed over the catalyst of Au on as-synthesized TS-1 that contained a small amount of anatase TiO2. The catalytic performance was studied by washing or nonwashing the catalyst precursor to modulate the content of purity (K, Cl) and then calcining the samples in O2 or H2 prior to reaction. The results show that the catalytic performance of Au/TS-1 can be improved without washing (more K+ and Au maintained) and O2 pretreatment. It was found that the calcination in O2 was able to maintain more metallic Au and form more surface-active oxygen species and thus providing a better yield of propylene oxide with the assistance of potassium. Interestingly, more acrolein can be produced over the catalysts with respect to the in situ calcination in O2 than that in H2 when the feed only contained 10% O2 and 10% propylene in argon, while there was no formation of propylene oxide. On the other hand, the catalyst precursor calcined in H2 prefers the formation of successive oxygenates of PO.
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3
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Abstract
The epoxidation of propene without forming a substantial amount of byproducts is one of the holy grails of catalysis. Supported Cu, Ag and Au catalysts are studied for this reaction and the activity of the supported metals is generally well understood. On the contrary, limited information is available on the influence of the support on the epoxide selectivity. The reaction of propene with equal amounts of hydrogen and oxygen was tested over gold nanoparticles deposited onto CeO2, TiO2, WO3, γ-Al2O3, SiO2, TiO2-SiO2 and titanosilicate-1. Several metal oxide supports caused further conversion of the synthesized propene oxide. Strongly acidic supports, such as WO3 and titanosilicate-1, catalyzed the isomerization of propene oxide towards propanal and acetone. Key factors for achieving high PO selectivity are having inert or neutralized surface sites, a low specific surface and/or a low density of surface -OH groups. This work provides insights and practical guidelines to which metal oxide support properties lead to which products in the reaction of propene in the presence of oxygen and hydrogen over supported gold catalysts.
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4
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Brindle J, Sufyan SA, Nigra MM. Support, composition, and ligand effects in partial oxidation of benzyl alcohol using gold–copper clusters. Catal Sci Technol 2022. [DOI: 10.1039/d2cy00137c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The effect of metallic composition, support, and ligands on catalytic performance using AuCu clusters in benzyl alcohol oxidation is investigated.
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Affiliation(s)
- Joseph Brindle
- Department of Chemical Engineering, University of Utah, Salt Lake City, Utah 84112, USA
| | - Sayed Abu Sufyan
- Department of Chemical Engineering, University of Utah, Salt Lake City, Utah 84112, USA
| | - Michael M. Nigra
- Department of Chemical Engineering, University of Utah, Salt Lake City, Utah 84112, USA
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5
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Tada K, Kitta M, Tanaka S. CO oxidation activity of Au on spinel titanate supports: Improvement of catalytic activity via alkali cation substitution from Li4Ti5O12 to Na3LiTi5O12. CHEM LETT 2021. [DOI: 10.1246/cl.210594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Kohei Tada
- Research Institute of Electrochemical Energy, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Mitsunori Kitta
- Research Institute of Electrochemical Energy, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Shingo Tanaka
- Research Institute of Electrochemical Energy, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31, Midorigaoka, Ikeda, Osaka 563-8577, Japan
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6
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Xiao TT, Wang GC. Crystal-plane-controlled selectivity and activity of copper catalysts in propylene oxidation with O 2. Catal Sci Technol 2021. [DOI: 10.1039/d1cy00007a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The selectivity of PO is inversely proportional to its activity on copper catalysts.
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Affiliation(s)
- Tian-Tian Xiao
- Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) and the
- Tianjin Key Lab and Molecule-Based Material Chemistry
- College of Chemistry
- Nankai University
- Tianjin 300071
| | - Gui-Chang Wang
- Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) and the
- Tianjin Key Lab and Molecule-Based Material Chemistry
- College of Chemistry
- Nankai University
- Tianjin 300071
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7
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Lu Z, Kunisch J, Gan Z, Bunian M, Wu T, Lei Y. Gold Catalysts Synthesized Using a Modified Incipient Wetness Impregnation Method for Propylene Epoxidation. ChemCatChem 2020. [DOI: 10.1002/cctc.202001053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zheng Lu
- Department of Chemical and Materials Engineering University of Alabama in Huntsville 301 Sparkman Drive Huntsville AL 35899 USA
| | - Jacob Kunisch
- Department of Chemical and Materials Engineering University of Alabama in Huntsville 301 Sparkman Drive Huntsville AL 35899 USA
| | - Zhuoran Gan
- Department of Chemical and Materials Engineering University of Alabama in Huntsville 301 Sparkman Drive Huntsville AL 35899 USA
| | - Muntaseer Bunian
- Department of Chemical and Materials Engineering University of Alabama in Huntsville 301 Sparkman Drive Huntsville AL 35899 USA
| | - Tianpin Wu
- X-ray Science Division Argonne National Laboratory 9700 South Cass Avenue Lemont IL 60439 USA
| | - Yu Lei
- Department of Chemical and Materials Engineering University of Alabama in Huntsville 301 Sparkman Drive Huntsville AL 35899 USA
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8
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García-Aguilar J, Fernández-Catalá J, Juan-Juan J, Such-Basáñez I, Chinchilla L, Calvino-Gámez J, Cazorla-Amorós D, Berenguer-Murcia Á. Novelty without nobility: Outstanding Ni/Ti-SiO2 catalysts for propylene epoxidation. J Catal 2020. [DOI: 10.1016/j.jcat.2020.04.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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9
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Ishida T, Murayama T, Taketoshi A, Haruta M. Importance of Size and Contact Structure of Gold Nanoparticles for the Genesis of Unique Catalytic Processes. Chem Rev 2019; 120:464-525. [DOI: 10.1021/acs.chemrev.9b00551] [Citation(s) in RCA: 249] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Tamao Ishida
- Department of Applied Chemistry for Environment, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
- Research Center for Gold Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Toru Murayama
- Department of Applied Chemistry for Environment, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
- Research Center for Gold Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Ayako Taketoshi
- Department of Applied Chemistry for Environment, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
- Research Center for Gold Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Masatake Haruta
- Research Center for Gold Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan
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10
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Lu Z, Liu X, Zhang B, Gan Z, Tang S, Ma L, Wu T, Nelson GJ, Qin Y, Turner CH, Lei Y. Structure and reactivity of single site Ti catalysts for propylene epoxidation. J Catal 2019. [DOI: 10.1016/j.jcat.2019.07.051] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Yu B, Ayvalı T, Wang ZQ, Gong XQ, Bagabas AA, Tsang SCE. Gas phase selective propylene epoxidation over La2O3-supported cubic silver nanoparticles. Catal Sci Technol 2019. [DOI: 10.1039/c9cy00567f] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It is shown that the Ag nanocube/La2O3 interface catalyses gas phase oxidation of propylene to propylene oxide cooperatively with enhanced selectivity and conversion. Dioxygen is preferentially activated and dissociated by La2O3(001) and the active atomic oxygen over the Ag(100) facet leads to selective propylene epoxidation.
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Affiliation(s)
- Bin Yu
- Wolfson Catalysis Centre
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Tuğçe Ayvalı
- Wolfson Catalysis Centre
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Zhi-Qiang Wang
- Key Laboratory for Advanced Materials
- Centre for Computational Chemistry and
- Research Institute of Industrial Catalysis
- Chemistry and Molecular Engineering
- East China University of Science and Technology
| | - Xue-Qing Gong
- Key Laboratory for Advanced Materials
- Centre for Computational Chemistry and
- Research Institute of Industrial Catalysis
- Chemistry and Molecular Engineering
- East China University of Science and Technology
| | - Abdulaziz A. Bagabas
- National Petrochemical Technology Center (NPTC)
- Materials Science Research Institute (MSRI)
- King Abdulaziz City for Science and Technology (KACST)
- Riyadh 11442
- Kingdom of Saudi Arabia
| | - S. C. Edman Tsang
- Wolfson Catalysis Centre
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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12
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Mononuclear gold species anchored on TS-1 framework as catalyst precursor for selective epoxidation of propylene. J Catal 2018. [DOI: 10.1016/j.jcat.2018.09.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Theoretical Studies on the Direct Propylene Epoxidation Using Gold-Based Catalysts: A Mini-Review. Catalysts 2018. [DOI: 10.3390/catal8100421] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Direct propylene epoxidation using Au-based catalysts is an important gas-phase reaction and is clearly a promising route for the future industrial production of propylene oxide (PO). For instance, gold nanoparticles or clusters that consist of a small number of atoms demonstrate unique and even unexpected properties, since the high ratio of surface to bulk atoms can provide new reaction pathways with lower activation barriers. Support materials can have a remarkable effect on Au nanoparticles or clusters due to charge transfer. Moreover, Au (or Au-based alloy, such as Au–Pd) can be loaded on supports to form active interfacial sites (or multiple interfaces). Model studies are needed to help probe the underlying mechanistic aspects and identify key factors controlling the activity and selectivity. The current theoretical/computational progress on this system is reviewed with respect to the molecular- and catalyst-level aspects (e.g., first-principles calculations and kinetic modeling) of propylene epoxidation over Au-based catalysts. This includes an analysis of H2 and O2 adsorption, H2O2 (OOH) species formation, epoxidation of propylene into PO, as well as possible byproduct formation. These studies have provided a better understanding of the nature of the active centers and the dominant reaction mechanisms, and thus, could potentially be used to design novel catalysts with improved efficiency.
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14
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Khetrapal NS, Wang LS, Zeng XC. Determination of CO Adsorption Sites on Gold Clusters Au n- ( n = 21-25): A Size Region That Bridges the Pyramidal and Core-Shell Structures. J Phys Chem Lett 2018; 9:5430-5439. [PMID: 30180587 DOI: 10.1021/acs.jpclett.8b02372] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We perform a joint photoelectron spectroscopy and theoretical study to investigate CO adsorption sites on midsized gold clusters, Au n- ( n = 21-25), a special size region that bridges the highly symmetric pyramidal cluster Au20- (Li et al. Science 2003, 299, 864) and the prevailing core-shell clusters starting from Au26- (Schaefer et al. ACS Nano 2014, 8, 7413). Particular attention is placed on whether the CO binding can significantly change structures of the host clusters in view of the fact that the size-dependent structural change already occurs for bare gold clusters in this size range. A transition from hollow-tubular to fused-planar structures is identified for the Au nCO- clusters even though the CO molecule mostly binds to an apex gold atom. The computed CO adsorption energy and HOMO-LUMO gap of the gold clusters suggest that among the five gold clusters the Au23- cluster exhibits the strongest CO binding and thereby could be a good catalytic model system.
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Affiliation(s)
- Navneet Singh Khetrapal
- Department of Chemistry , University of Nebraska-Lincoln , Lincoln , Nebraska 68588 , United States
| | - Lai-Sheng Wang
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Xiao Cheng Zeng
- Department of Chemistry , University of Nebraska-Lincoln , Lincoln , Nebraska 68588 , United States
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15
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Tada K, Koga H, Hayashi A, Kondo Y, Kawakami T, Yamanaka S, Okumura M. Theoretical Clarification of the Coexistence of Cl Effects on Au/TiO2: The Interaction between Au Clusters and the TiO2 Surface, and the Aggregation of Au Clusters on the TiO2 Surface. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2017. [DOI: 10.1246/bcsj.20160359] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Kohei Tada
- Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Hiroaki Koga
- Element Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520
| | - Akihide Hayashi
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Yudai Kondo
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Takashi Kawakami
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Shusuke Yamanaka
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Mitsutaka Okumura
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
- Element Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Katsura, Kyoto 615-8520
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16
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Li Z, Wang Y, Zhang J, Wang D, Ma W. Better performance for gas-phase epoxidation of propylene using H2 and O2 at lower temperature over Au/TS-1 catalyst. CATAL COMMUN 2017. [DOI: 10.1016/j.catcom.2016.12.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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17
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Perez Ferrandez DM, Herguedas Fernandez I, Teley MP, de Croon MH, Schouten JC, Nijhuis TA. Kinetic study of the selective oxidation of propene with O2 over Au–Ti catalysts in the presence of water. J Catal 2015. [DOI: 10.1016/j.jcat.2015.07.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Puértolas B, Hill A, García T, Solsona B, Torrente-Murciano L. In-situ synthesis of hydrogen peroxide in tandem with selective oxidation reactions: A mini-review. Catal Today 2015. [DOI: 10.1016/j.cattod.2014.03.054] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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19
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Au/TS-1 catalyst prepared by deposition–precipitation method for propene epoxidation with H2/O2: Insights into the effects of slurry aging time and Si/Ti molar ratio. J Catal 2015. [DOI: 10.1016/j.jcat.2015.02.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Gas-phase epoxidation of propylene in the presence of H2 and O2 over small gold ensembles in uncalcined TS-1. J Catal 2014. [DOI: 10.1016/j.jcat.2014.02.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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Enhanced reaction rate for gas-phase epoxidation of propylene using H2 and O2 by Cs promotion of Au/TS-1. J Catal 2013. [DOI: 10.1016/j.jcat.2013.05.023] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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22
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23
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Lu X, Zhao G, Lu Y. Propylene epoxidation with O2 and H2: a high-performance Au/TS-1 catalyst prepared via a deposition–precipitation method using urea. Catal Sci Technol 2013. [DOI: 10.1039/c3cy00339f] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Lee WS, Lai LC, Cem Akatay M, Stach EA, Ribeiro FH, Delgass WN. Probing the gold active sites in Au/TS-1 for gas-phase epoxidation of propylene in the presence of hydrogen and oxygen. J Catal 2012. [DOI: 10.1016/j.jcat.2012.08.021] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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25
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Lee WS, Cem Akatay M, Stach EA, Ribeiro FH, Nicholas Delgass W. Reproducible preparation of Au/TS-1 with high reaction rate for gas phase epoxidation of propylene. J Catal 2012. [DOI: 10.1016/j.jcat.2011.12.019] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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26
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27
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Hutchings GJ, Edwards JK. Application of Gold Nanoparticles in Catalysis. METAL NANOPARTICLES AND NANOALLOYS 2012. [DOI: 10.1016/b978-0-08-096357-0.00001-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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28
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Huang J, Haruta M. Gas-phase propene epoxidation over coinage metal catalysts. RESEARCH ON CHEMICAL INTERMEDIATES 2011. [DOI: 10.1007/s11164-011-0424-6] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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29
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Qi C, Huang J, Bao S, Su H, Akita T, Haruta M. Switching of reactions between hydrogenation and epoxidation of propene over Au/Ti-based oxides in the presence of H2 and O2. J Catal 2011. [DOI: 10.1016/j.jcat.2011.03.028] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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30
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Gaudet J, Bando KK, Song Z, Fujitani T, Zhang W, Su DS, Oyama ST. Effect of gold oxidation state on the epoxidation and hydrogenation of propylene on Au/TS-1. J Catal 2011. [DOI: 10.1016/j.jcat.2011.03.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Bracey CL, Carley AF, Edwards JK, Ellis PR, Hutchings GJ. Understanding the effect of thermal treatments on the structure of CuAu/SiO2 catalysts and their performance in propene oxidation. Catal Sci Technol 2011. [DOI: 10.1039/c0cy00003e] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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32
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Chen J, Halin SJA, Schouten JC, Nijhuis TA. Kinetic study of propylene epoxidation with H2 and O2 over Au/Ti–SiO2 in the explosive regime. Faraday Discuss 2011; 152:321-36; discussion 393-413. [DOI: 10.1039/c1fd00014d] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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33
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Nijhuis TA, Chen J, Kriescher SMA, Schouten JC. The Direct Epoxidation of Propene in the Explosive Regime in a Microreactor—A Study into the Reaction Kinetics. Ind Eng Chem Res 2010. [DOI: 10.1021/ie1004306] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- T. Alexander Nijhuis
- Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory for Chemical Reactor Engineering, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Jiaqi Chen
- Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory for Chemical Reactor Engineering, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Stefanie M. A. Kriescher
- Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory for Chemical Reactor Engineering, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - Jaap C. Schouten
- Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory for Chemical Reactor Engineering, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
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34
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Effect of composition and promoters in Au/TS-1 catalysts for direct propylene epoxidation using H2 and O2. Catal Today 2009. [DOI: 10.1016/j.cattod.2008.09.005] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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35
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Cavani F, Teles JH. Sustainability in catalytic oxidation: an alternative approach or a structural evolution? CHEMSUSCHEM 2009; 2:508-534. [PMID: 19536755 DOI: 10.1002/cssc.200900020] [Citation(s) in RCA: 354] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This Review documents some examples of recent innovations in the field of catalytic selective oxidation from an industrial point of view. The use of alkanes as building blocks for the synthesis of bulk chemicals and intermediates is discussed, along with the main properties that catalysts should possess in order to efficiently catalyse the selective oxidation of these hydrocarbons. The currently developed processes for propene oxide and new processes under investigation for the synthesis of adipic acid are also described, highlighting innovative aspects for a better sustainability of the chemical industry.
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Affiliation(s)
- Fabrizio Cavani
- Dipartimento di Chimica Industriale e dei Materiali, ALMA MATER STUDIORUM Università di Bologna, Italy.
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Cui F, Hua Z, Wei C, Li J, Gao Z, Shi J. Highly dispersed Au nanoparticles incorporated mesoporous TiO2 thin films with ultrahigh Au content. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b912016e] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Wang F, Qi C, Ma J. The study of the uncalcined Au catalyst and inorganic salts on direct gas-phase epoxidation of propylene. CATAL COMMUN 2007. [DOI: 10.1016/j.catcom.2007.03.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Highly Active/Selective Heterogeneous Catalyst Co/Ts-1 for Epoxidation of Styrene by Molecular Oxygen: Effects of Catalyst Preparation Conditions and Reaction Conditions on the Reaction. Catal Letters 2007. [DOI: 10.1007/s10562-007-9273-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lu J, Zhang X, Bravo-Suárez JJ, Tsubota S, Gaudet J, Oyama ST. Kinetics of propylene epoxidation using H2 and O2 over a gold/mesoporous titanosilicate catalyst. Catal Today 2007. [DOI: 10.1016/j.cattod.2007.02.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Taylor B, Lauterbach J, Delgass WN. The effect of mesoporous scale defects on the activity of Au/TS-1 for the epoxidation of propylene. Catal Today 2007. [DOI: 10.1016/j.cattod.2007.01.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Joshi AM, Tucker MH, Delgass WN, Thomson KT. CO adsorption on pure and binary-alloy gold clusters: a quantum chemical study. J Chem Phys 2007; 125:194707. [PMID: 17129150 DOI: 10.1063/1.2375094] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
We performed density-functional theory analysis of nondissociative CO adsorption on 22 binary Au-alloy (Au(n)M(m)) clusters: n=0-3, m=0-3, and m+n=2 (dimers) or 3 (trimers), M=Cu/Ag/Pd/Pt. We report basis-set superposition error corrections to adsorption energies and include both internal energy of adsorption (DeltaU(ads)) and Gibbs free energy of adsorption (DeltaG(ads)) at standard conditions (298.15 K and 1 atm). We found onefold (atop) CO binding on all the clusters except Pd2 (twofold/bridged), Pt2 (twofold/bridged), and Pd3 (threefold). In agreement with the experimental results, we found that CO adsorption is thermodynamically favorable on pure Au/Cu clusters but not on pure Ag clusters and also observed the following adsorption affinity trend: Pd>Pt>Au>Cu>Ag. For alloy dimers we found the following patterns: Au2>M Au>M2 (M=Ag/Cu) and M2>M Au>Au2 (M=Pd/Pt). Alloying Ag/Cu dimers with (more reactive) Au enhanced adsorption and the opposite effect was observed for PdPt dimers. The Ag-Au, Cu-Au, and Pd-Au trimers followed the trends observed on dimers: Au3>M Au2>M2Au>M3 (M=Ag/Cu) and Pd3>Pd2Au>PdAu2>Au3. Interestingly, Pt-Au trimers reacted differently and alloying with Au systematically increased the adsorption affinity: PtAu2>Pt2Au>Pt3>Au3. A strikingly different behavior of Pt is also manifested by the triplet spin state and onefold (atop) binding in Pt3-CO which is in contradiction with the singlet spin state and threefold binding in Pd3-CO. We found a linear correlation between CO binding energy (BE) and elongation of the CO bond. For Ag-Au and Cu-Au clusters, the increase in CO BE (and elongation of the C-O bond which is probably due to the back donation) is accompanied by the decrease in the cluster-CO distance suggesting that the donation (from 5sigma highest occupied molecular orbital in CO to cluster lowest unoccupied molecular orbital) mechanism also contributes to the BE. For Pd-Au clusters, the cluster-CO distance (and CO bond length) increases with increase in the BE, suggesting that the donation mechanism may not be important for those clusters. No clear trend was observed for Pt-Au clusters.
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Affiliation(s)
- Ajay M Joshi
- School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA.
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Joshi AM, Delgass WN, Thomson KT. Analysis of O2 Adsorption on Binary−Alloy Clusters of Gold: Energetics and Correlations. J Phys Chem B 2006; 110:23373-87. [PMID: 17107188 DOI: 10.1021/jp063610f] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We report a B3LYP density-functional theory (DFT) analysis of O(2) adsorption on 27 Au(n)M(m) (m, n = 0-3 and m + n = 2 or 3; M = Cu, Ag, Pd, Pt, and Na) clusters. The LANL2DZ pseudopotential and corresponding double-zeta basis set was used for heavy atoms, while a 6-311+G(3df) basis set was used for Na and O. We employed basis-set superposition error (BSSE) corrections in the electronic adsorption energies at 0 K (deltaE(ads)) and also calculated adsorption thermodynamics at standard conditions (298.15 K and 1 atm), i.e., internal energy of adsorption (deltaU(ads)) and Gibbs free energy of adsorption (deltaG(ads)). Natural Bond Orbital (NBO) analysis showed that all the clusters donated electron density to adsorbed O(2) and we successfully predicted intuitive linear correlations between the NBO charge on adsorbed O(2), O-O bond length, and O-O stretching frequency. Although there was no clear trend in the O(2) binding energy (BE = -deltaE(ads)) on pure and alloy dimers, we found the following interesting trend for trimers: BE (MAu(2)) < BE (M(3)) < or = BE (M(2)Au). The alloy trimers containing only one Au atom are most reactive toward O(2) while those with two Au atoms are least reactive. These trends are discussed in the context of the ensemble effect and coulomb interactions. We found an approximate linear correlation between the O(2) BE and charge transfer to O(2) for all 27 clusters. The clusters having strongly electropositive Na atoms (e.g., Na(3) and Na(2)Au) donated almost one full electron to adsorbed O(2), and the BE is maximum on these clusters. Although O(2) dissociation is likely in such cases, we have restricted this study to trends in the adsorption of molecular O(2) only. We also found an approximate linear correlation between the charge transfer and BE versus energy difference between the bare-cluster HOMO and O(2) LUMOs, which we speculate to be a fundamental descriptor of the reactivity of small clusters toward O(2). Part of the scatter in these correlations is attributed to the differences in the O(2) binding orientations on different clusters (geometric effect). Relatively higher bare-cluster HOMO energy eases the charge transfer to adsorbed O(2) and enhances the reactivity toward O(2). The Frontier Orbital Picture (FOP) is not always useful in predicting the most favorable O(2) binding site on clusters. It successfully predicted the cluster-O(2) ground-state configurations for 10 clusters, but failed for the others. Finally, the energetics of fragmentation suggest that the bare and O(2)-covered clusters reported here are stable.
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Affiliation(s)
- Ajay M Joshi
- School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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Wells DH, Joshi AM, Delgass WN, Thomson KT. A Quantum Chemical Study of Comparison of Various Propylene Epoxidation Mechanisms Using H2O2and TS-1 Catalyst. J Phys Chem B 2006; 110:14627-39. [PMID: 16869565 DOI: 10.1021/jp062368+] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a comparison of the following prominent propylene epoxidation mechanisms using H2O2/TS-1 at a consistent density functional theory (DFT) method: (1) the Sinclair and Catlow mechanism on tripodal site through Ti-OOH species, (2) the Vayssilov and van Santen mechanism on tetrapodal site without Ti-OOH formation, (3) the Munakata et al. mechanism involving peroxy (Ti-O-O-Si) species, (4) the defect site mechanism with a partial silanol nest, and (5) the defect site mechanism with a full silanol nest. We have reproduced the previously published (ethylene epoxidation) pathways (1-3) for propylene epoxidation using larger and SiH3-terminated cluster models of the T-6 crystallographic site of TS-1. Mechanism 5 is a new mechanism reported here for the first time. The use of a consistent level of theory for all the pathways allows for the first time a meaningful comparison of the energetics representing the aforementioned pathways. We have rigorously identified the important reaction intermediates and transition states and carried out a detailed thermochemical analysis at 298.15 K and 1 atm. On the basis of the Gibbs free energy of activation, the Sinclair and Catlow mechanism (Delta G(act) = 7.9 kcal/mol) is the energetically most favorable mechanism, which is, however, likely to operate on the external surface of TS-1 due to the tripodal nature of the Ti site in their model. The newly reported defect site mechanism (with a full silanol nest) is a competitive propylene epoxidation mechanism. There are two main steps: (1) hydroperoxy formation (Delta G(act) = 8.9 kcal/mol) and (2) propylene epoxidation (Delta G(act) = 4.6 kcal/mol). This mechanism is likely to represent the chemistry occurring inside the TS-1 pores in the liquid-phase epoxidation (H2O2/TS-1) process and could operate in direct gas-phase epoxidation (H2/O2/Au/TS-1) as well. If only the propylene epoxidation step is considered, then the Munakata peroxo intermediate (Si-O-O-Ti) is the most reactive intermediate, which can epoxidize propylene with a negligible activation barrier. However, formation of the Munakata intermediate is a very activated step (Delta G(act) = 19.8 kcal/mol). We also explain the trends in the activation barriers in different mechanisms using geometric and electronic features such as orientation of adsorbed H2O2 and propylene, hydrogen bonding, O1-Ti bond distance in the Ti-O1-O2-H intermediate, and O1-O2 stretching in the transition state. Implications of different Ti site models are also discussed in light of the nature of external/internal and nondefect/defect sites of TS-1.
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Affiliation(s)
- David H Wells
- School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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Joshi AM, Delgass WN, Thomson KT. Adsorption of Small Aun (n = 1−5) and Au−Pd Clusters Inside the TS-1 and S-1 Pores. J Phys Chem B 2006; 110:16439-51. [PMID: 16913775 DOI: 10.1021/jp061754o] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We used a hybrid quantum-mechanics/molecular-mechanics (QM/MM) approach to simulate the adsorption of Au(n)() (n = 1-5), AuPd, and Au(2)Pd(2) clusters inside the TS-1 and S-1 pores. We studied nondefect and metal-vacancy defect sites in TS-1 and S-1 for a total of four different environments around the T6 crystallographic site. We predict stronger binding of all clusters near Ti sites in Ti-substituted framework compared to adsorption near Si sites-consistent with the experimental finding of a direct correlation between the Ti-loading and the Au-loading on the Au/TS-1 catalysts with high Si/Ti ratio. The cluster binding is also stronger near lattice-metal vacancies compared to fully coordinated, nondefect sites. In all the cases, a trend of binding energy (BE) versus Au cluster size (n) shows a peak at around n = 3-4. Our results show that there is enough room for the attack of H(2)O(2) on the Ti-defect site even with Au(1-4) adsorbed-a result that supports the possibility of H(2)O(2) spillover from the Au clusters to the adjacent Ti-defect sites. Mulliken charge analysis indicates that in all the cases there is electron density transfer to adsorbed clusters from the zeolite lattice. In the case of both gas-phase and adsorbed Au-Pd clusters, all the Pd atoms were positively charged, and all the Au atoms were negatively charged due to the higher electron-affinity of Au. We also found a correlation between the BE and the charge transfer to the clusters (the higher the charge transfer to the clusters, the higher the BE), and a universal correlation was found for Au(2-5) when BE and charge transfer were plotted on a per atom basis. A relatively larger charge transfer to the adsorbed clusters was found for the Ti sites versus the Si sites, and for the defect sites versus the nondefect sites. The trends in the BE were corroborated using Gibbs free energy of adsorption (DeltaG(ads)), and the implications of DeltaG(ads) in sintering of Au clusters are also discussed. Our results confirm that electronic factors such as cluster-charging are potentially important support effects for the Au/TS-1 catalyst.
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Affiliation(s)
- Ajay M Joshi
- School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA.
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Kobayashi H, Shimodaira Y. Density functional study of propylene oxidation on Ag and Au surfaces. Comparison to ethylene oxidation. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.theochem.2005.08.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Joshi AM, Delgass WN, Thomson KT. Partial Oxidation of Propylene to Propylene Oxide over a Neutral Gold Trimer in the Gas Phase: A Density Functional Theory Study. J Phys Chem B 2006; 110:2572-81. [PMID: 16471857 DOI: 10.1021/jp054809f] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report a B3LYP study of a novel mechanism for propylene epoxidation using H(2) and O(2) on a neutral Au(3) cluster, including full thermodynamics and pre-exponential factors. A side-on O(2) adsorption on Au(3) is followed by dissociative addition of H(2) across one of the Au-O bonds (DeltaE(act) = 2.2 kcal/mol), forming a hydroperoxy intermediate (OOH) and a lone H atom situated on the Au(3) cluster. The more electrophilic O atom (proximal to the Au) of the Au-OOH group attacks the C=C of an approaching propylene to form propylene oxide (PO) with an activation barrier of 19.6 kcal/mol. We predict the PO desorption energy from the Au(3) cluster with residual OH and H to be 11.5 kcal/mol. The catalytic cycle can be closed in two different ways. In the first subpathway, OH and H, hosted by the same terminal Au atom, combine to form water (DeltaE(act) = 26.5 kcal/mol). We attribute rather a high activation barrier of this step to the breaking of the partial bond between the H atom and the central Au atom in the transition state. Upon water desorption (DeltaE(des) = 9.9 kcal/mol), the Au(3) is regenerated (closure). In the second subpathway, H(2) is added across the Au-OH bond to form water and another Au-H bond (DeltaE(act) = 22.6 kcal/mol). Water spontaneously desorbs to form an obtuse angle Au(3) dihydride, with one H atom on the terminal Au atom and the other bridging the same terminal Au atom and the central Au atom. A slightly activated rearrangement to a symmetric triangular Au(3) intermediate with two equivalent Au-H bonds, addition of O(2) into the Au-H bond, and rotation reforms the hydroperoxy intermediate in the main cycle. On the basis of the DeltaG(act), which contains contribution from both pre-exponetial factor and activation energy, we identify the propylene epoxidation step as the actual rate-determining step (RDS) in both the pathways. The activation barrier of the RDS (epoxidation step: DeltaE(act) = 19.6 kcal/mol) is in the same range as that in the published computationally investigated olefin epoxidation mechanisms involving Ti sites (without Au involved) indicating that isolated Au clusters and possibly Au clusters on non-Ti supports can be active for gas-phase partial oxidation, even though cooperative mechanisms involving Au clusters/Ti-based-supports may be favored.
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Affiliation(s)
- Ajay M Joshi
- School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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Joshi AM, Delgass WN, Thomson KT. Comparison of the Catalytic Activity of Au3, Au4+, Au5, and Au5- in the Gas-Phase Reaction of H2 and O2 to Form Hydrogen Peroxide: A Density Functional Theory Investigation. J Phys Chem B 2005; 109:22392-406. [PMID: 16853917 DOI: 10.1021/jp052653d] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report a detailed density functional theory (B3LYP) analysis of the gas-phase H2O2 formation from H2 and O2 on Au3, Au4+, Au5, and Au5-. We find that H2, which interacts only weakly with the Au clusters, is dissociatively added across the Au-O bond, upon interaction with AunO2. One H atom is captured by the adsorbed O2 to form the hydroperoxy intermediate (OOH), while the other H atom is captured by the Au atom. Once formed, the hydroperoxy intermediate acts as a precursor for the closed-loop catalytic cycle. An important common feature of all the pathways is that the rate-determining step of the catalytic cycle is the second H2 addition to form H2O2. The H2O2 desorption is followed by O2 addition to AunH2 to form the hydroperoxy intermediate, thus leading to the closure of the cycle. On the basis of the Gibbs free energy of activation, out of these four clusters, Au4+ is most active for the formation of the H2O2. The 0 K electronic energy of activation and the DeltaGact at the standard conditions are 12.6 and 16.6 kcal/mol respectively. The natural bond orbital charge analysis suggests that the Au clusters remain positively charged (oxidic) in almost all the stages of the cycle. This is interesting in the context of the recent experimental evidence for the activity of cationic Au in CO oxidation and water-gas shift catalysts. We have also found preliminary evidence for a correlation between the activation barrier for the first H2 addition and the O2 binding energy on the Au cluster. It suggests that the minimum activation barrier for the first H2 addition is expected for the Au clusters with 7.0-9.0 kcal/mol O2 binding energy, i.e., in the midrange of the expected interaction energy. This represents a balance between more favorable H2 dissociation when the Aun-O2 interaction is weaker and high O2 coverage when the interaction is stronger. On the basis of this work, we predict that the hydroperoxy intermediate formation can be both thermodynamically and kinetically viable only in a narrow range of the O2 binding energy (10.0-12.0 kcal/mol)-a useful estimate for computationally screening Au-cluster-based catalysts. We also show that a competitive channel for the OOH desorption exists. Thus, in propylene epoxidation both OOH radicals and H2O2 can attack the active Ti in/on the Au/TS-1 and generate the Ti-OOH sites, which can convert propylene to propylene oxide.
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Affiliation(s)
- Ajay M Joshi
- School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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