1
|
Abstract
Methane is an abundant resource and its direct conversion into value-added chemicals has been an attractive subject for its efficient utilization. This method can be more efficient than the present energy-intensive indirect conversion of methane via syngas, a mixture of CO and H2. Among the various approaches for direct methane conversion, the selective oxidation of methane into methane oxygenates (e.g., methanol and formaldehyde) is particularly promising because it can proceed at low temperatures. Nevertheless, due to low product yields this method is challenging. Compared with the liquid-phase partial oxidation of methane, which frequently demands for strong oxidizing agents in protic solvents, gas-phase selective methane oxidation has some merits, such as the possibility of using oxygen as an oxidant and the ease of scale-up owing to the use of heterogeneous catalysts. Herein, we summarize recent advances in the gas-phase partial oxidation of methane into methane oxygenates, focusing mainly on its conversion into formaldehyde and methanol.
Collapse
|
2
|
Bao X, Behrens M, Ertl G, Fu Q, Knop-Gericke A, Lunkenbein T, Muhler M, Schmidt CM, Trunschke A. A Career in Catalysis: Robert Schlögl. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xinhe Bao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), 457 Zhongshan Road, Dalian 116023, People’s Republic of China
| | - Malte Behrens
- Institute of Inorganic Chemistry, Solid State Chemistry and Catalysis, Kiel University, Max-Eyth-Straße 2, 24118 Kiel, Germany
| | - Gerhard Ertl
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Departments of Physical Chemistry and Inorganic Chemistry, Faradayweg 4-6, 14195 Berlin, Germany
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), 457 Zhongshan Road, Dalian 116023, People’s Republic of China
| | - Axel Knop-Gericke
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Departments of Physical Chemistry and Inorganic Chemistry, Faradayweg 4-6, 14195 Berlin, Germany
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstraße 34-36, 45470 Mülheim, Germany
| | - Thomas Lunkenbein
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Departments of Physical Chemistry and Inorganic Chemistry, Faradayweg 4-6, 14195 Berlin, Germany
| | - Martin Muhler
- Industrial Chemistry, Ruhr University Bochum, Universitätsstraße 150, 44780 Bochum, Germany
| | - Christoph M. Schmidt
- RWI - Leibniz-Institut für Wirtschaftsforschung, Hohenzollernstraße 1-3, 45128 Essen, Germany
| | - Annette Trunschke
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Departments of Physical Chemistry and Inorganic Chemistry, Faradayweg 4-6, 14195 Berlin, Germany
| |
Collapse
|
3
|
Abstract
We review oxygen K-edge X-ray absorption spectra of both molecules and solids. We start with an overview of the main experimental aspects of oxygen K-edge X-ray absorption measurements including X-ray sources, monochromators, and detection schemes. Many recent oxygen K-edge studies combine X-ray absorption with time and spatially resolved measurements and/or operando conditions. The main theoretical and conceptual approximations for the simulation of oxygen K-edges are discussed in the Theory section. We subsequently discuss oxygen atoms and ions, binary molecules, water, and larger molecules containing oxygen, including biomolecular systems. The largest part of the review deals with the experimental results for solid oxides, starting from s- and p-electron oxides. Examples of theoretical simulations for these oxides are introduced in order to show how accurate a DFT description can be in the case of s and p electron overlap. We discuss the general analysis of the 3d transition metal oxides including discussions of the crystal field effect and the effects and trends in oxidation state and covalency. In addition to the general concepts, we give a systematic overview of the oxygen K-edges element by element, for the s-, p-, d-, and f-electron systems.
Collapse
Affiliation(s)
- Federica Frati
- Inorganic
chemistry and catalysis, Debye Institute for Nanomaterials Science, Utrecht University, 3584CG Utrecht, The Netherlands
| | | | - Frank M. F. de Groot
- Inorganic
chemistry and catalysis, Debye Institute for Nanomaterials Science, Utrecht University, 3584CG Utrecht, The Netherlands
| |
Collapse
|
4
|
Che‐Galicia G, López‐Isunza F, Corona‐Jiménez E, Castillo‐Araiza CO. The role of kinetics and heat transfer on the performance of an industrial wall‐cooled packed‐bed reactor: Oxidative dehydrogenation of ethane. AIChE J 2019. [DOI: 10.1002/aic.16900] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Gamaliel Che‐Galicia
- Facultad de Ingeniería QuímicaBenemérita Universidad Autónoma de Puebla Puebla Mexico
| | - Felipe López‐Isunza
- Laboratory of Catalytic Reactor Engineering Applied to Chemical and Biological Systems (LCRE), Departamento de Ingeniería de Procesos e HidráulicaUniversidad Autónoma Metropolitana‐Iztapalapa Ciudad de México Mexico
| | - Edith Corona‐Jiménez
- Facultad de Ingeniería QuímicaBenemérita Universidad Autónoma de Puebla Puebla Mexico
| | - Carlos O. Castillo‐Araiza
- Laboratory of Catalytic Reactor Engineering Applied to Chemical and Biological Systems (LCRE), Departamento de Ingeniería de Procesos e HidráulicaUniversidad Autónoma Metropolitana‐Iztapalapa Ciudad de México Mexico
| |
Collapse
|
5
|
Xie Q, Zhang H, Kang J, Cheng J, Zhang Q, Wang Y. Oxidative Dehydrogenation of Propane to Propylene in the Presence of HCl Catalyzed by CeO2 and NiO-Modified CeO2 Nanocrystals. ACS Catal 2018. [DOI: 10.1021/acscatal.8b00650] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Quanhua Xie
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Huamin Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jincan Kang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jun Cheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Qinghong Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Ye Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| |
Collapse
|
6
|
Sprenger P, Kleist W, Grunwaldt JD. Recent Advances in Selective Propylene Oxidation over Bismuth Molybdate Based Catalysts: Synthetic, Spectroscopic, and Theoretical Approaches. ACS Catal 2017. [DOI: 10.1021/acscatal.7b01149] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paul Sprenger
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Wolfgang Kleist
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
- Institute
of Catalysis Research and Technology, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
| | - Jan-Dierk Grunwaldt
- Institute
for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
- Institute
of Catalysis Research and Technology, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
| |
Collapse
|
7
|
Wang Y, Chen SL, Gao YL, Cao YQ, Zhang Q, Chang WK, Benziger JB. Enhanced Methanol to Olefin Catalysis by Physical Mixtures of SAPO-34 Molecular Sieve and MgO. ACS Catal 2017. [DOI: 10.1021/acscatal.7b01285] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ya Wang
- State
Key Laboratory of Heavy Oil Processing and Department of Chemical
Engineering, China University of Petroleum, Beijing, 102249, People’s Republic of China
| | - Sheng-Li Chen
- State
Key Laboratory of Heavy Oil Processing and Department of Chemical
Engineering, China University of Petroleum, Beijing, 102249, People’s Republic of China
| | - Yu-Li Gao
- State
Key Laboratory of Heavy Oil Processing and Department of Chemical
Engineering, China University of Petroleum, Beijing, 102249, People’s Republic of China
| | - Ying-Qian Cao
- State
Key Laboratory of Heavy Oil Processing and Department of Chemical
Engineering, China University of Petroleum, Beijing, 102249, People’s Republic of China
| | - Qi Zhang
- State
Key Laboratory of Heavy Oil Processing and Department of Chemical
Engineering, China University of Petroleum, Beijing, 102249, People’s Republic of China
| | - Wei-Ke Chang
- State
Key Laboratory of Heavy Oil Processing and Department of Chemical
Engineering, China University of Petroleum, Beijing, 102249, People’s Republic of China
| | - Jay B. Benziger
- Department
of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
8
|
Thompson LM, Jarrold CC, Hratchian HP. Explaining the MoVO4− photoelectron spectrum: Rationalization of geometric and electronic structure. J Chem Phys 2017; 146:104301. [DOI: 10.1063/1.4977418] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Lee M. Thompson
- Chemistry and Chemical Biology, University of California, Merced, California 95343, USA
| | - Caroline C. Jarrold
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA
| | - Hrant P. Hratchian
- Chemistry and Chemical Biology, University of California, Merced, California 95343, USA
| |
Collapse
|
9
|
Schlögl R. Selective Oxidation: From a Still Immature Technology to the Roots of Catalysis Science. Top Catal 2016. [DOI: 10.1007/s11244-016-0684-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
10
|
Kühn S, Weber D, Lerch M, Ressler T. Effects of Anion Substitution in (Mo,V) 5O 14on Catalytic Performance in Selective Propene Oxidation to Acrolein. ChemCatChem 2016. [DOI: 10.1002/cctc.201501076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- S. Kühn
- Department of Chemistry; Technische Universität Berlin; Strasse des 17. Juni 135 10623 Berlin Germany
| | - D. Weber
- Department of Chemistry; Technische Universität Berlin; Strasse des 17. Juni 135 10623 Berlin Germany
| | - M. Lerch
- Department of Chemistry; Technische Universität Berlin; Strasse des 17. Juni 135 10623 Berlin Germany
| | - T. Ressler
- Department of Chemistry; Technische Universität Berlin; Strasse des 17. Juni 135 10623 Berlin Germany
| |
Collapse
|
11
|
Thompson LM, Hratchian HP. Modeling the Photoelectron Spectra of MoNbO2– Accounting for Spin Contamination in Density Functional Theory. J Phys Chem A 2015; 119:8744-51. [DOI: 10.1021/acs.jpca.5b04625] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lee M. Thompson
- Chemistry and Chemical Biology, University of California, Merced, California 95343, United States
| | - Hrant P. Hratchian
- Chemistry and Chemical Biology, University of California, Merced, California 95343, United States
| |
Collapse
|
12
|
|
13
|
Abstract
A heterogeneous catalyst is a functional material that continually creates active sites with its reactants under reaction conditions. These sites change the rates of chemical reactions of the reactants localized on them without changing the thermodynamic equilibrium between the materials.
Collapse
Affiliation(s)
- Robert Schlögl
- Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany) http://www.fhi-berlin.mpg.de http://www.cec.mpg.de; Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim a.d. Ruhr (Germany).
| |
Collapse
|
14
|
Hamid SBA, Schlögl R. The Impact of Nanoscience in Heterogeneous Catalysis. THE NANO‐MICRO INTERFACE 2015:405-430. [DOI: 10.1002/9783527679195.ch20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
|
15
|
Guo Z, Liu B, Zhang Q, Deng W, Wang Y, Yang Y. Recent advances in heterogeneous selective oxidation catalysis for sustainable chemistry. Chem Soc Rev 2014; 43:3480-524. [PMID: 24553414 DOI: 10.1039/c3cs60282f] [Citation(s) in RCA: 448] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Oxidation catalysis not only plays a crucial role in the current chemical industry for the production of key intermediates such as alcohols, epoxides, aldehydes, ketones and organic acids, but also will contribute to the establishment of novel green and sustainable chemical processes. This review is devoted to dealing with selective oxidation reactions, which are important from the viewpoint of green and sustainable chemistry and still remain challenging. Actually, some well-known highly challenging chemical reactions involve selective oxidation reactions, such as the selective oxidation of methane by oxygen. On the other hand some important oxidation reactions, such as the aerobic oxidation of alcohols in the liquid phase and the preferential oxidation of carbon monoxide in hydrogen, have attracted much attention in recent years because of their high significance in green or energy chemistry. This article summarizes recent advances in the development of new catalytic materials or novel catalytic systems for these challenging oxidation reactions. A deep scientific understanding of the mechanisms, active species and active structures for these systems are also discussed. Furthermore, connections among these distinct catalytic oxidation systems are highlighted, to gain insight for the breakthrough in rational design of efficient catalytic systems for challenging oxidation reactions.
Collapse
Affiliation(s)
- Zhen Guo
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.
| | | | | | | | | | | |
Collapse
|
16
|
Wu LB, Wu LH, Yang WM, Frenkel AI. Study of the local structure and oxidation state of iron in complex oxide catalysts for propylene ammoxidation. Catal Sci Technol 2014. [DOI: 10.1039/c4cy00197d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A combination of X-ray absorption, Raman and UV-visible spectroscopy reveals the competing redox reactions during the deactivation of Fe-based complex catalysts.
Collapse
Affiliation(s)
- Li-bin Wu
- Shanghai Research Institute of Petrochemical Technology
- Shanghai 201208, China
- Physics Department
- Yeshiva University
- New York, USA
| | - Liang-hua Wu
- Shanghai Research Institute of Petrochemical Technology
- Shanghai 201208, China
| | - Wei-min Yang
- Shanghai Research Institute of Petrochemical Technology
- Shanghai 201208, China
| | | |
Collapse
|
17
|
Eichelbaum M, Glaum R, Hävecker M, Wittich K, Heine C, Schwarz H, Dobner CK, Welker-Nieuwoudt C, Trunschke A, Schlögl R. Towards Physical Descriptors of Active and Selective Catalysts for the Oxidation ofn-Butane to Maleic Anhydride. ChemCatChem 2013. [DOI: 10.1002/cctc.201200953] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
18
|
van Schooneveld MM, Suljoti E, Campos-Cuerva C, Gosselink RW, van der Eerden AMJ, Schlappa J, Zhou KJ, Monney C, Schmitt T, de Groot FMF. Transition-Metal Nanoparticle Oxidation in a Chemically Nonhomogenous Environment Revealed by 2p3d Resonant X-ray Emission. J Phys Chem Lett 2013; 4:1161-1166. [PMID: 26282036 DOI: 10.1021/jz4002696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
X-ray absorption spectroscopy (XAS) is often employed in fields such as catalysis to determine whether transition-metal nanoparticles are oxidized. Here we show 2p3/2 XAS and 2p3d resonant X-ray emission spectroscopy (RXES) data of oleate-coated cobalt nanoparticles with average diameters of 4.0, 4.2, 5.0, 8.4, and 15.2 nm. Two particle batches were exposed to air for different periods of time, whereas the others were measured as synthesized. In the colloidal nanoparticles, the cobalt sites can have different chemical environments (metallic/oxidized/surface-coordinated), and it is shown that most XAS data cannot distinguish whether the nanoparticles are oxidized or surface-coated. In contrast, the high-energy resolution RXES spectra reveal whether more than the first metal layer is oxidized based on the unique energetic separation of spectral features related to the formal metal (X-ray fluorescence) or to a metal oxide (d-d excitations). This is the first demonstration of metal 2p3d RXES as a novel surface science tool.
Collapse
Affiliation(s)
| | | | | | | | | | - Justine Schlappa
- ‡Paul Scherrer Institut (PSI), Swiss Light Source, CH-5232 Villigen, Switzerland
| | - Kejin J Zhou
- ‡Paul Scherrer Institut (PSI), Swiss Light Source, CH-5232 Villigen, Switzerland
| | - Claude Monney
- ‡Paul Scherrer Institut (PSI), Swiss Light Source, CH-5232 Villigen, Switzerland
| | - Thorsten Schmitt
- ‡Paul Scherrer Institut (PSI), Swiss Light Source, CH-5232 Villigen, Switzerland
| | | |
Collapse
|
19
|
Conte M, Liu X, Murphy DM, Whiston K, Hutchings GJ. Cyclohexane oxidation using Au/MgO: an investigation of the reaction mechanism. Phys Chem Chem Phys 2012; 14:16279-85. [PMID: 23132082 DOI: 10.1039/c2cp43363j] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The liquid phase oxidation of cyclohexane was undertaken using Au/MgO and the reaction mechanism was investigated by means of continuous wave (CW) EPR spectroscopy employing the spin trapping technique. Activity tests aimed to determine the conversion and selectivity of Au/MgO catalyst showed that Au was capable of selectivity control to cyclohexanol formation up to 70%, but this was accompanied by a limited enhancement in conversion when compared with the reaction in the absence of catalyst. In contrast, when radical initiators were used, in combination with Au/MgO, an activity comparable to that observed in industrial processes at ca. 5% conversion was found, with retained high selectivity. By studying the free radical autoxidation of cyclohexane and the cyclohexyl hydroperoxide decomposition in the presence of spin traps, we show that Au nanoparticles are capable of an enhanced generation of cyclohexyl alkoxy radicals, and the role of Au is identified as a promoter of the catalytic autoxidation processes, therefore demonstrating that the reaction proceeds via a radical chain mechanism.
Collapse
Affiliation(s)
- Marco Conte
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
| | | | | | | | | |
Collapse
|
20
|
Waller SE, Mann JE, Rothgeb DW, Jarrold CC. Study of MoNbOy (y = 2–5) Anion and Neutral Clusters Using Photoelectron Spectroscopy and Density Functional Theory Calculations: Impact of Spin Contamination on Single Point Calculations. J Phys Chem A 2012; 116:9639-52. [DOI: 10.1021/jp306790z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sarah E. Waller
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington,
Indiana 47405, United States
| | - Jennifer E. Mann
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington,
Indiana 47405, United States
| | - David W. Rothgeb
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington,
Indiana 47405, United States
| | - Caroline C. Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington,
Indiana 47405, United States
| |
Collapse
|
21
|
|
22
|
|
23
|
Conte M, Chechik V. Spin trapping of radical intermediates in gas phase catalysis: cyclohexane oxidation over metal oxides. Chem Commun (Camb) 2010; 46:3991-3. [DOI: 10.1039/c0cc00157k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
24
|
Steric Effect on the Catalytic Performance of the Selective Oxidation of Alcohols Over Novel Crystalline Mo–V–O Oxide. Top Catal 2008. [DOI: 10.1007/s11244-008-9109-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
25
|
Kampe P, Giebeler L, Samuelis D, Kunert J, Drochner A, Haass F, Adams AH, Ott J, Endres S, Schimanke G, Buhrmester T, Martin M, Fuess H, Vogel H. Heterogeneously catalysed partial oxidation of acrolein to acrylic acid—structure, function and dynamics of the V–Mo–W mixed oxides. Phys Chem Chem Phys 2007; 9:3577-89. [PMID: 17612723 DOI: 10.1039/b700098g] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The major objective of this research project was to reach a microscopic understanding of the structure, function and dynamics of V-Mo-(W) mixed oxides for the partial oxidation of acrolein to acrylic acid. Different model catalysts (from binary and ternary vanadium molybdenum oxides up to quaternary oxides with additional tungsten) were prepared via a solid state preparation route and hydrochemical preparation of precursors by spray-drying or crystallisation with subsequent calcination. The phase composition was investigated ex situ by XRD and HR-TEM. Solid state prepared samples are characterised by crystalline phases associated to suitable phase diagrams. Samples prepared from crystallised and spray-dried precursors show crystalline phases which are not part of the phase diagram. Amorphous or nanocrystalline structures are only found in tungsten doped samples. The kinetics of the partial oxidation as well as the catalysts' structure have been studied in situ by XAS, XRD, temperature programmed reaction and reduction as well as by a transient isotopic tracing technique (SSITKA). The reduction and re-oxidation kinetics of the bulk phase have been evaluated by XAS. A direct influence not only of the catalysts' composition but also of the preparation route is shown. Altogether correlations are drawn between structure, oxygen dynamics and the catalytic performance in terms of activity, selectivity and long-term stability. A model for the solid state behaviour under reaction conditions has been developed. Furthermore, isotope exchange experiments provided a closer image of the mechanism of the selective acrolein oxidation. Based on the in situ characterisation in combination with micro kinetic modelling a detailed reaction model which describes the oxygen exchange and the processes at the catalyst more precisely is discussed.
Collapse
Affiliation(s)
- Philip Kampe
- Darmstadt University of Technology, Faculty of Chemistry, Technical Chemistry, Petersenstr. 20, D-64287, Darmstadt, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Gouma PI, Prasad AK, Iyer KK. Selective nanoprobes for 'signalling gases'. NANOTECHNOLOGY 2006; 17:S48-S53. [PMID: 21727353 DOI: 10.1088/0957-4484/17/4/008] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The use of arrays of chemical detectors has been realized in electronic nose applications. Recently attention has been focused on the application of e-Noses in the medical arena. These are electronic devices that typically employ non-selective gas sensitive elements for the monitoring of odours and other gaseous analytes. Currently, the lack of relative specificity to a mixture of gaseous analytes for these sensing elements makes the use of pattern recognition algorithms to process the signal and match the acquired data profile to a known pattern necessary, thus identifying the signature of the odour or gas detected. An alternative approach to chemical detection through the use of small arrays (two or three elements) of selective gas sensors made of nanostructured semiconducting films and membranes is described in this work. Sensor selectivity is defined here as higher sensitivity to a given gas or class of gases in the presence of interfering gaseous species. Transition metal oxides are key sensing elements of resistive type chemical detectors. A given oxide may be found in several polymorph phases, each having a distinct structural configuration. Gas-oxide interactions are strongly dependent on the 'structure sensitivity' of the polymorph used in sensing. This paper reviews the effect of polymorphism on the gas specificity and the importance of nanoscale processing for stabilizing the desirable oxide phases, and it introduces a gas-polymorph selection library for building the next generation of gas sensing systems with inherent selectivity to be used as non-invasive disease diagnosis tools.
Collapse
Affiliation(s)
- P I Gouma
- Department of Materials Science and Engineering, 314, Old Engineering Building, SUNY at Stony Brook, Stony Brook, NY 11794-2275, USA
| | | | | |
Collapse
|
27
|
Schimanke G, Martin M, Kunert J, Vogel H. Characterization of Mo-V-W Mixed Oxide Catalysts byex situ andin situ X-Ray Absorption Spectroscopy. Z Anorg Allg Chem 2005. [DOI: 10.1002/zaac.200500064] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
28
|
|
29
|
Liu C, Ozkan US. Spectroscopic and Structural Characterization of Chlorine Loading Effects on Mo/Si:Ti Catalysts in Oxidative Dehydrogenation of Ethane. J Phys Chem A 2005; 109:1260-8. [PMID: 16833438 DOI: 10.1021/jp045726m] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structural changes induced in a silica-titania mixed-oxide support (1:1 molar ratio) by chlorine addition at different loading levels, their relation to the structural characteristics of supported MoOx species over the support, and their correlation with ethane oxidative dehydrogenation (ODH) activity have been examined. The molybdenum and chlorine precursors are incorporated into the Si/Ti support network as it forms during gelation by using a "one-pot" modified sol-gel/coprecipitation technique. In situ X-ray diffraction during calcination shows the Si/Ti 1:1 mixed-oxide support is in a state of nanodispersed anatase titania over amorphous silica. With the addition of molybdenum and chlorine modifier, this anatase feature becomes more pronounced, indicating a decreased dispersion of titania. The effective titania surface area on the chlorine-doped Si:Ti support obtained from 2-propanol temperature-programmed reaction supports this observation. Raman spectra of dehydrated samples point to an enhanced interaction of MoOx species with silica at the expense of titania. X-ray photoelectron spectroscopic results show that, without forming a molybdenum chloride, the presence of chlorine significantly alters the relative surface concentration of Si vs Ti, the electronic structure of the surface MoOx species, and the oxygen environment around supported MoOx species in the Si/Ti network. Secondary ion mass spectrometry detected the existence of SiCl fragments from the mass spectra, which provides molecular insight into the location of chlorine in Mo/Si:Ti catalysts. The observed increase in ethane ODH selectivity with chlorine modification may be ascribed to the MoOx species sharing more complex ligands with silica and titania with the indirect participation of chlorine. Steady-state isotopic transient kinetic analysis (SSITKA) is used to to examine the oxygen insertion and exchange mechanisms. The catalysts show very little oxygen exchange with the gas phase in the absence of a reaction medium. During the steady-state ODH reaction, lattice oxygen appears to be the primary source of oxygen in the formation of water and CO2.
Collapse
Affiliation(s)
- Chang Liu
- Department of Chemical Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | | |
Collapse
|
30
|
Grunwaldt JD, Baiker A. Axial variation of the oxidation state of Pt-Rh/Al2O3 during partial methane oxidation in a fixed-bed reactor: An in situ X-ray absorption spectroscopy study. Catal Letters 2005. [DOI: 10.1007/s10562-005-0770-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
31
|
Grunwaldt JD, Baiker A. In situ spectroscopic investigation of heterogeneous catalysts and reaction media at high pressure. Phys Chem Chem Phys 2005; 7:3526-39. [PMID: 16294227 DOI: 10.1039/b509667g] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In situ characterization of catalysts by means of complementary spectroscopic techniques can be regarded as the first step towards rational catalyst design. Spurred by the growing interest of catalytic reactions in supercritical fluids and by several industrial reactions traditionally performed at high pressure (>10 bar), new demands and challenges are put to in situ spectroscopic characterization of heterogeneous catalytic reactions. In this article, we discuss the development and the use of spectroscopic and related techniques suitable for elucidating such high-pressure reactions. Selected examples from phase behaviour studies with a view cell, investigations with transmission and attenuated total reflection (ATR) infrared spectroscopy as well as X-ray absorption spectroscopy (EXAFS, XANES), are presented to show the strategies, opportunities and limitations of such high pressure in situ studies. Different facets appear to be important to gain insight into catalytic reactions in supercritical fluids: the identification of the phase behaviour of the reaction mixture, the behaviour of the fluid inside the porous catalyst, the processes occurring at the solid-fluid interface, the possible dissolution of active species and, similar as in gas-solid reactions, the establishment of structure-activity relationships.
Collapse
Affiliation(s)
- Jan-Dierk Grunwaldt
- Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Hönggerberg HCI, CH-8093 Zürich, Switzerland.
| | | |
Collapse
|
32
|
Liu C, Ozkan US. Effect of chlorine on redox and adsorption characteristics of Mo/Si:Ti catalysts in the oxidative dehydrogenation of ethane. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.molcata.2004.03.049] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
33
|
Choi HC, Jung YM, Kim SB. Characterization of the electrochemical reactions in the Li(1+x)V3O8/Li cell by soft X-ray absorption spectroscopy and two-dimensional correlation analysis. APPLIED SPECTROSCOPY 2003; 57:984-990. [PMID: 14661842 DOI: 10.1366/000370203322258959] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We applied soft X-ray absorption spectroscopy (XAS) and two-dimensional (2D) correlation analysis to the first lithium insertion-extraction cycle in a Li(1+x)V3O8/Li cell in order to investigate the electrochemical reactions of lithium with the Li(1+x)V3O8 electrode. The V L(II,III)-edge and O K-edge spectra of the Li(1+x)V3O8 electrode were obtained for varying electrode lithium content. The insertion of lithium leads to the reduction of the V5+ species present in the pristine Li(1+x)V3O8 electrode, and to the red shift and the broadening of the spectral features of the V L(II,III) edge compared to those of the pristine electrode. In the extraction process, the main spectral features at the highest value of the extraction of lithium show some differences compared to the features of the pristine electrode spectrum due to the residual lithium ions in the Li(1+x)V3O8 structure. The O K-edge spectra revealed that the insertion of lithium mainly affects the V 4sp-O 2p bonds and consequently induces a change in bonding geometry. The 2D correlation analysis of these spectra clearly shows that V-O bonds are significantly perturbed by the insertion-extraction of lithium into the Li(1+x)V3O8 electrode.
Collapse
Affiliation(s)
- Hyun Chul Choi
- Laboratory for Vibrational Spectroscopy, Department of Chemistry, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Republic of Korea
| | | | | |
Collapse
|
34
|
Propane and propylene adsorption effects over MoOx-based catalysts induced by low levels of alkali doping. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1169(02)00476-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
35
|
Watson RB, Ozkan US. Spectroscopic and Structural Characterization of Low-Level Alkali Doping Effects on Mo/Silica−Titania Catalysts. J Phys Chem B 2002. [DOI: 10.1021/jp025512+] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
36
|
Reaction Mechanism and Control of Selectivity in Catalysis by Oxides: Some Challenges and Open Questions. Int J Mol Sci 2001. [DOI: 10.3390/i2050183] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|