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Nifant'ev I, Komarov P, Sadrtdinova G, Safronov V, Kolosov N, Ivchenko P. Mechanistic Insights of Ethylene Polymerization on Phillips Chromium Catalysts. Polymers (Basel) 2024; 16:681. [PMID: 38475365 DOI: 10.3390/polym16050681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Silica-supported chromium oxide catalysts, also named Phillips chromium catalysts (PCCs), provide more than half of the world's production of high- and medium-density polyethylenes. PCCs are usually prepared in the Cr(VI)/SiO2 form, which is subjected to reductive activation. It has been explicitly proven that CO reduces Cr(VI) to Cr(II) species that initiate ethylene polymerization; ethylene activates Cr(VI) sites as well, but the nature of the catalytic species is complicated by the presence of the ethylene oxidation products. It is widely accepted that the catalytic species are of a Cr(III)-alkyl nature, but this common assumption faces the challenge of "extra" hydrogen: the formation of similar species under the action of even-electron reducing agents requires an additional H atom. Relatively recently, it was found that saturated hydrocarbons can also activate CrOx/SiO2, and alkyl fragments turn out to be bonded with a polyethylene chain. In recent years, there have been numerous experimental and theoretical studies of the structure and chemistry of PCCs at the different stages of preparation and activation. The use of modern spectral methods (such as extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES), and others); operando IR, UV-vis, EPR, and XAS spectroscopies; and theoretical approaches (DFT modeling, machine learning) clarified many essential aspects of the mechanisms of CrOx/SiO2 activation and catalytic behavior. Overall, the Cosse-Arlman mechanism of polymerization on Cr(III)-alkyl centers is confirmed in many works, but its theoretical support required the development of nontrivial and contentious mechanistic concepts of Cr(VI)/SiO2 or Cr(II)/SiO2 activation. On the other hand, conflicting experimental data continue to be obtained, and certain mechanistic concepts are being developed with the use of outdated models. Strictly speaking, the main question of what type of catalytic species, Cr(II), Cr(III), or Cr(IV), comes into polymerization still has not received an unambiguous answer. The role of the chemical nature of the support-through the prism of the nature, geometry, and distribution of the active sites-is also not clear in depth. In the present review, we endeavored to summarize and discuss the recent studies in the field of the preparation, activation, and action of PCCs, with a focus on existing contradictions in the interpretation of the experimental and theoretical results.
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Affiliation(s)
- Ilya Nifant'ev
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
- Department of Chemistry, M.V. Lomonosov Moscow University, 1-3 Leninskie Gory, 119991 Moscow, Russia
| | - Pavel Komarov
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
| | - Guzelia Sadrtdinova
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
- Faculty of Chemistry, National Research University Higher School of Economics, Myasnitskaya St. 20, 101100 Moscow, Russia
| | | | | | - Pavel Ivchenko
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
- Department of Chemistry, M.V. Lomonosov Moscow University, 1-3 Leninskie Gory, 119991 Moscow, Russia
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2
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Brigiano FS, Gierada M, Tielens F, Pietrucci F. Mechanism and Free-Energy Landscape of Peptide Bond Formation at the Silica–Water Interface. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Flavio Siro Brigiano
- General Chemistry (ALGC), Materials Modeling Group, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Maciej Gierada
- General Chemistry (ALGC), Materials Modeling Group, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Faculty of Chemical Engineering and Technology, Cracow University of Technology, ul. Warszawska 24, 31-155 Kraków, Poland
| | - Frederik Tielens
- General Chemistry (ALGC), Materials Modeling Group, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Fabio Pietrucci
- Sorbonne Université, Muséum National d’Histoire Naturelle, UMR CNRS 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, F-75005 Paris, France
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3
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Myradova M, Węgrzynowicz A, Węgrzyniak A, Gierada M, Jodlowski P, Łojewska J, Handzlik J, Michorczyk P. Tuning metathesis performance of molybdenum oxide-based catalyst by silica support acidity modulation and high temperature pretreatment. Catal Sci Technol 2022. [DOI: 10.1039/d1cy02064a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molybdenum oxide-based catalysts containing 5 wt. % of Mo obtained by simple impregnation of silica mesoporous support were studied in olefin metathesis reaction at 50 °C. Effect of support modification...
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4
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Piovano A, Groppo E. Flexible ligands in heterogeneous catalysts for olefin polymerization: Insights from spectroscopy. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214258] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Handzlik J, Kurleto K, Gierada M. Computational Insights into Active Site Formation during Alkene Metathesis over a MoO x/SiO 2 Catalyst: The Role of Surface Silanols. ACS Catal 2021. [DOI: 10.1021/acscatal.1c03912] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Jarosław Handzlik
- Faculty of Chemical Engineering and Technology, Cracow University of Technology, ul. Warszawska 24, Kraków 31-155, Poland
| | - Kamil Kurleto
- Faculty of Chemical Engineering and Technology, Cracow University of Technology, ul. Warszawska 24, Kraków 31-155, Poland
| | - Maciej Gierada
- Faculty of Chemical Engineering and Technology, Cracow University of Technology, ul. Warszawska 24, Kraków 31-155, Poland
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6
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Monai M, Gambino M, Wannakao S, Weckhuysen BM. Propane to olefins tandem catalysis: a selective route towards light olefins production. Chem Soc Rev 2021; 50:11503-11529. [PMID: 34661210 DOI: 10.1039/d1cs00357g] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
On-purpose synthetic routes for propylene production have emerged in the last couple of decades in response to the increasing demand for plastics and a shift to shale gas feedstocks for ethylene production. Propane dehydrogenation (PDH), an efficient and selective route to produce propylene, saw booming investments to fill the so-called propylene gap. In the coming years, however, a fluctuating light olefins market will call for flexibility in end-product of PDH plants. This can be achieved by combining PDH with propylene metathesis in a single step, propane to olefins (PTO), which allows production of mixtures of propylene, ethylene and butenes, which are important chemical building blocks for a.o. thermoplastics. The metathesis technology introduced by Phillips in the 1960s and mostly operated in reverse to produce propylene, is thus undergoing a renaissance of scientific and technological interest in the context of the PTO reaction. In this review, we will describe the state-of-the-art of PDH, propylene metathesis and PTO reactions, highlighting the open challenges and opportunities in the field. While the separate PDH and metathesis reactions have been extensively studied in the literature, understanding the whole PTO tandem-catalysis system will require new efforts in theoretical modelling and operando spectroscopy experiments, to gain mechanistic insights into the combined reactions and finally improve catalytic selectivity and stability for on-purpose olefins production.
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Affiliation(s)
- Matteo Monai
- Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Marianna Gambino
- Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Sippakorn Wannakao
- SCG Chemicals Co., Ltd, 1 Siam-Cement Rd, Bang sue, Bangkok 1080, Thailand
| | - Bert M Weckhuysen
- Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
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Liu K, Liu Z, Cheng R, He X, Liu B. Mechanistic study of vanadium-modified and sulfation-modified Phillips catalyst. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2021.111777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Trummer D, Searles K, Algasov A, Guda SA, Soldatov AV, Ramanantoanina H, Safonova OV, Guda AA, Copéret C. Deciphering the Phillips Catalyst by Orbital Analysis and Supervised Machine Learning from Cr Pre-edge XANES of Molecular Libraries. J Am Chem Soc 2021; 143:7326-7341. [PMID: 33974429 DOI: 10.1021/jacs.0c10791] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Unveiling the nature and the distribution of surface sites in heterogeneous catalysts, and for the Phillips catalyst (CrO3/SiO2) in particular, is still a grand challenge despite more than 60 years of research. Commonly used references in Cr K-edge XANES spectral analysis rely on bulk materials (Cr-foil, Cr2O3) or molecules (CrCl3) that significantly differ from actual surface sites. In this work, we built a library of Cr K-edge XANES spectra for a series of tailored molecular Cr complexes, varying in oxidation state, local coordination environment, and ligand strength. Quantitative analysis of the pre-edge region revealed the origin of the pre-edge shape and intensity distribution. In particular, the characteristic pre-edge splitting observed for Cr(III) and Cr(IV) molecular complexes is directly related to the electronic exchange interactions in the frontier orbitals (spin-up and -down transitions). The series of experimental references was extended by theoretical spectra for potential active site structures and used for training the Extra Trees machine learning algorithm. The most informative features of the spectra (descriptors) were selected for the prediction of Cr oxidation states, mean interatomic distances in the first coordination sphere, and type of ligands. This set of descriptors was applied to uncover the site distribution in the Phillips catalyst at three different stages of the process. The freshly calcined catalyst consists of mainly Cr(VI) sites. The CO-exposed catalyst contains mainly Cr(II) silicates with a minor fraction of Cr(III) sites. The Phillips catalyst exposed to ethylene contains mainly highly coordinated Cr(III) silicates along with unreduced Cr(VI) sites.
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Affiliation(s)
- David Trummer
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Keith Searles
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Alexander Algasov
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090.,Institute of Mathematics, Mechanics and Computer Science, Southern Federal University, Milchakova 8a, Rostov-on-Don, Russia, 344090
| | - Sergey A Guda
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090.,Institute of Mathematics, Mechanics and Computer Science, Southern Federal University, Milchakova 8a, Rostov-on-Don, Russia, 344090
| | - Alexander V Soldatov
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090
| | | | | | - Alexander A Guda
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
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Deng S, Liu Z, Liu B, Jin Y. Unravelling the Role of Al‐alkyl Cocatalyst for the VO
x
/SiO
2
Ethylene Polymerization Catalyst: Diethylaluminum Chloride Vs. Triethylaluminum. ChemCatChem 2021. [DOI: 10.1002/cctc.202001929] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Shiheng Deng
- Key Laboratory for Biobased Materials and Energy of Ministry of Education College of Materials and Energy South China Agricultural University Guangzhou 510630 P.R. China
- Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510630 P.R. China
| | - Zhen Liu
- State Key Laboratory of Chemical Engineering School of Chemical Engineering East China University of Science and Technology Shanghai 200237 P.R. China
| | - Boping Liu
- Key Laboratory for Biobased Materials and Energy of Ministry of Education College of Materials and Energy South China Agricultural University Guangzhou 510630 P.R. China
- Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510630 P.R. China
| | - Yulong Jin
- Key Laboratory for Biobased Materials and Energy of Ministry of Education College of Materials and Energy South China Agricultural University Guangzhou 510630 P.R. China
- Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510630 P.R. China
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Deraet X, Turek J, Alonso M, Tielens F, Cottenier S, Ayers PW, Weckhuysen BM, De Proft F. Reactivity of Single Transition Metal Atoms on a Hydroxylated Amorphous Silica Surface: A Periodic Conceptual DFT Investigation. Chemistry 2021; 27:6050-6063. [PMID: 33368741 DOI: 10.1002/chem.202004660] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/15/2020] [Indexed: 11/08/2022]
Abstract
The drive to develop maximal atom-efficient catalysts coupled to the continuous striving for more sustainable reactions has led to an ever-increasing interest in single-atom catalysis. Based on a periodic conceptual density functional theory (cDFT) approach, fundamental insights into the reactivity and adsorption of single late transition metal atoms supported on a fully hydroxylated amorphous silica surface have been acquired. In particular, this investigation revealed that the influence of van der Waals dispersion forces is especially significant for a silver (98 %) or gold (78 %) atom, whereas the oxophilicity of the Group 8-10 transition metals plays a major role in the interaction strength of these atoms on the irreducible SiO2 support. The adsorption energies for the less-electronegative row 4 elements (Fe, Co, Ni) ranged from -1.40 to -1.92 eV, whereas for the heavier row 5 and 6 metals, with the exception of Pd, these values are between -2.20 and -2.92 eV. The deviating behavior of Pd can be attributed to a fully filled d-shell and, hence, the absence of the hybridization effects. Through a systematic analysis of cDFT descriptors determined by using three different theoretical schemes, the Fermi weighted density of states approach was identified as the most suitable for describing the reactivity of the studied systems. The main advantage of this scheme is the fact that it is not influenced by fictitious Coulomb interactions between successive, charged reciprocal cells. Moreover, the contribution of the energy levels to the reactivity is simultaneously scaled based on their position relative to the Fermi level. Finally, the obtained Fermi weighted density of states reactivity trends show a good agreement with the chemical characteristics of the investigated metal atoms as well as the experimental data.
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Affiliation(s)
- Xavier Deraet
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Elsene, Brussels, Belgium
| | - Jan Turek
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Elsene, Brussels, Belgium
| | - Mercedes Alonso
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Elsene, Brussels, Belgium
| | - Frederik Tielens
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Elsene, Brussels, Belgium
| | - Stefaan Cottenier
- Department of Electrical Energy, Metals, Mechanical Constructions and Systems, Ghent University, Technologiepark 46, 9052, Zwijnaarde, Belgium.,Center for Molecular Modeling, Ghent University, Technologiepark 46, 9052, Zwijnaarde, Belgium
| | - Paul W Ayers
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario, L8S 4M1, Canada
| | - Bert M Weckhuysen
- Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Frank De Proft
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Elsene, Brussels, Belgium
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11
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Jongkind MK, Meirer F, Bossers KW, ten Have IC, Ohldag H, Watts B, van Kessel T, Friederichs N, Weckhuysen BM. Influence of Metal-Alkyls on Early-Stage Ethylene Polymerization over a Cr/SiO 2 Phillips Catalyst: A Bulk Characterization and X-ray Chemical Imaging Study. Chemistry 2021; 27:1688-1699. [PMID: 32729972 PMCID: PMC7898848 DOI: 10.1002/chem.202002632] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/22/2020] [Indexed: 12/03/2022]
Abstract
The Cr/SiO2 Phillips catalyst has taken a central role in ethylene polymerization since its invention in 1953. The uniqueness of this catalyst is related to its ability to produce broad molecular weight distribution (MWD) PE materials as well as that no co-catalysts are required to attain activity. Nonetheless, co-catalysts in the form of metal-alkyls can be added for scavenging poisons, enhancing catalyst activity, reducing the induction period, and tailoring polymer characteristics. The activation mechanism and related polymerization mechanism remain elusive, despite extensive industrial and academic research. Here, we show that by varying the type and amount of metal-alkyl co-catalyst, we can tailor polymer properties around a single Cr/SiO2 Phillips catalyst formulation. Furthermore, we show that these different polymer properties exist in the early stages of polymerization. We have used conventional polymer characterization techniques, such as size exclusion chromatography (SEC) and 13 C NMR, for studying the metal-alkyl co-catalyst effect on short-chain branching (SCB), long-chain branching (LCB) and molecular weight distribution (MWD) at the bulk scale. In addition, scanning transmission X-ray microscopy (STXM) was used as a synchrotron technique to study the PE formation in the early stages: allowing us to investigate the produced type of early-stage PE within one particle cross-section with high energy resolution and nanometer scale spatial resolution.
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Affiliation(s)
- Maarten K. Jongkind
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Florian Meirer
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Koen W. Bossers
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Iris C. ten Have
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Hendrik Ohldag
- Advanced Light Source, MicroscopyLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA
- Department of Materials Science and EngineeringStanford University450 Serra MallStanfordCA943505USA
- Department of PhysicsUniversity of California Santa Cruz1156 High StreetSanta CruzCA95064USA
| | - Benjamin Watts
- Laboratory for Synchotron Radiation—Condensed Matter (LSC)Paul Scherrer Institute (PSI)Forschungsstrasse 1115232VilligenSwitzerland
| | - Theo van Kessel
- Technology and Innovation DepartmentSABICUrmonderbaan 226167 RDGeleenThe Netherlands
| | - Nic. Friederichs
- Technology and Innovation DepartmentSABICUrmonderbaan 226167 RDGeleenThe Netherlands
| | - Bert M. Weckhuysen
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
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Tielens F, Gierada M, Handzlik J, Calatayud M. Characterization of amorphous silica based catalysts using DFT computational methods. Catal Today 2020. [DOI: 10.1016/j.cattod.2019.03.062] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Khan SA, Vandervelden CA, Scott SL, Peters B. Grafting metal complexes onto amorphous supports: from elementary steps to catalyst site populationsviakernel regression. REACT CHEM ENG 2020. [DOI: 10.1039/c9re00357f] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We use transition state theory, kernel regression, and population balance modeling techniques to model the grafting of metal complexes onto amorphous catalyst supports.
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Affiliation(s)
- Salman A. Khan
- Department of Chemical Engineering
- University of California
- Santa Barbara
- USA
| | | | - Susannah L. Scott
- Department of Chemical Engineering
- University of California
- Santa Barbara
- USA
- Department of Chemistry & Biochemistry
| | - Baron Peters
- Department of Chemical & Biomolecular Engineering
- University of Illinois at Urbana-Champaign
- Urbana
- USA
- Department of Chemistry
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Groppo E, Martino GA, Piovano A, Barzan C. The Active Sites in the Phillips Catalysts: Origins of a Lively Debate and a Vision for the Future. ACS Catal 2018. [DOI: 10.1021/acscatal.8b02521] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elena Groppo
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| | - Giorgia Antonina Martino
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| | - Alessandro Piovano
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| | - Caterina Barzan
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
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