A5085930816- Catalytic Processes in Materials Science
- Zeolite Catalysis and Synthesis
- Catalysis and Oxidation Reactions
- Mesoporous Materials and Catalysis
- Catalysis and Hydrodesulfurization Studies
- Metal-Organic Frameworks: Synthesis and Applications
- X-ray Diffraction in Crystallography
- Catalysis for Biomass Conversion
- Advanced NMR Techniques and Applications
- Catalysts for Methane Reforming
- Electrocatalysts for Energy Conversion
- Nanomaterials for catalytic reactions
- Crystallization and Solubility Studies
- Chemical Synthesis and Characterization
- Ammonia Synthesis and Nitrogen Reduction
- Spectroscopy Techniques in Biomedical and Chemical Research
- Thermochemical Biomass Conversion Processes
- Advanced Photocatalysis Techniques
- 2D Materials and Applications
- Spectroscopy and Quantum Chemical Studies
- Polyoxometalates: Synthesis and Applications
- Clay minerals and soil interactions
- Machine Learning in Materials Science
- Spectroscopy and Chemometric Analyses
- Advanced Chemical Physics Studies
Haldor Topsoe (Denmark)
2015-2024
Danish Geotechnical Society
2017-2020
Capital Region of Denmark
2017
University of Oslo
2012
University of Turin
2008
Norwegian University of Science and Technology
2008
Fritz Haber Institute of the Max Planck Society
2002-2007
Max Planck Institute of Colloids and Interfaces
2004-2005
Martin Luther University Halle-Wittenberg
2005
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2005
Liquid hydrocarbon fuels play an essential part in the global energy chain, owing to their high density and easy transportability. Olefins a similar role production of consumer goods. In post-oil society, fuel olefin will rely on alternative carbon sources, such as biomass, coal, natural gas, CO(2). The methanol-to-hydrocarbons (MTH) process is key step routes, can be tuned into gasoline-rich (methanol gasoline; MTG) or olefin-rich olefins; MTO) product mixtures by proper choice catalyst...
For the first time, standard and fast selective catalytic reduction (SCR) of NO by NH3 are described in a complete cycle that is able to produce correct stoichiometry while allowing adsorption desorption stable molecules only. The SCR reaction coupling activation O2 with reaction, enabled release NO2. According scheme, can be divided into an oxidation catalyst + NH3; these steps together constitute cycle. Furthermore, both required reduction, finally, or NO2 leads same state catalyst. These...
Cu-SSZ-13 is a highly active NH3-SCR catalyst for the abatement of harmful nitrogen oxides (NO x , = 1, 2) from exhausts lean-burn engines. The study Cu-speciation occurring upon thermal dehydration key step understanding enhanced catalytic properties this material and identifying SCR sites their redox capability. Herein, we combined FTIR, X-ray absorption (XAS) emission (XES) spectroscopies with DFT computational analysis to elucidate nature location most abundant Cu in activated catalyst....
A novel nonaqueous route has been applied for the preparation of nanocrystalline magnetite. In a simple one-pot reaction process, iron(III) acetylacetonate was dissolved in benzyl alcohol and treated an autoclave between 175 200 °C. This approach leads to monocrystalline magnetite particles with sizes ranging from 12 25 nm, as evidenced by X-ray analysis, HRTEM, Raman Mossbauer spectroscopy. The isolated can be redispersed either polar or nonpolar solvents coating them just after synthesis...
Cu-SSZ-13 has been characterized by different spectroscopic techniques and compared with Cu-ZSM-5 Cu-β similar Si/Al Cu/Al ratios prepared the same ion exchange procedure. On vacuum activated samples, low temperature FTIR spectroscopy allowed us to appreciate a high concentration of reduced copper centres, i.e. isolated Cu(+) ions located in environments, able form Cu(+)(N2), Cu(+)(CO)n (n = 1, 2, 3), Cu(+)(NO)n 2) upon interaction N2, CO NO probe molecules, respectively. Low FTIR, DRUV-Vis...
Cu-exchanged zeolites possess active sites that are able to cleave the C–H bond of methane at temperatures ≤200 °C, enabling its selective partial oxidation methanol. Herein we explore this process over Cu-SSZ-13 materials. We combine activity tests and X-ray absorption spectroscopy (XAS) thoroughly investigate influence reaction parameters material elemental composition on productivity Cu speciation during key steps. find CuII moieties responsible for conversion formed in presence O2 high...
The small-pore Cu-CHA zeolite is today the object of intensive research efforts to rationalize its outstanding performance in NH3-assisted selective catalytic reduction (SCR) harmful nitrogen oxides and unveil SCR mechanism. Herein we exploit operando X-ray spectroscopies monitor catalyst action during NH3-SCR 150–400 °C range, targeting Cu oxidation state, mobility, preferential N or O ligation as a function reaction temperature. By combining XANES, EXAFS, vtc-XES, unambiguously identify...
In the typical NH3-SCR temperature range (100-500 °C), ammonia is one of main adsorbed species on acidic sites Cu-SSZ-13 catalyst. Therefore, study at high a key step for understanding its role in catalytic cycle. We employed different spectroscopic techniques to investigate nature complexes occurring upon NH3 interaction. particular, FTIR spectroscopy revealed formation species, that is, (i) bonded copper centers, (ii) Brønsted sites, and (iii) NH4(+)·nNH3 associations. XANES XES allowed us...
The direct conversion of methane to methanol (MTM) is a reaction that has the potential disrupt great part synthesis gas-derived chemical industry. However, despite many decades research, active enough catalysts and suitable processes for industrial application are still not available. Recently, several copper-exchanged zeolites have shown considerable activity selectivity in MTM reaction. Understanding nature site these materials essential any further development field. Herein, we apply...
The small pore Cu-CHA zeolite is attracting increasing attention as a versatile platform to design novel single-site catalysts for deNO x applications and the direct conversion of methane methanol. Understanding at atomic scale how catalyst composition influences Cu-species formed during thermal activation key step unveil relevant composition-activity relationships. Herein, we explore by in situ XAS impact on temperature-dependent Cu-speciation reducibility. Advanced multivariate analysis...
The methanol-to-hydrocarbon (MTH) reaction, a process in which low-value carbon-rich feedstocks are converted to value-added petrochemical products, is studied over one-dimensional 10-ring zeolites: ZSM-22 (TON), ZSM-23 (MTT), ZSM-48 (*MRE), and EU-1 (EUO). latter three little as MTH catalysts were expected display interesting product-shape-selective properties. influence of slight differences channel systems the materials (size shape) on product distribution stability investigated under...
Abstract Flüssige Kohlenwasserstoffe nehmen aufgrund ihrer hohen Energiedichte und guten Transportfähigkeit eine Schlüsselrolle in der globalen Energieversorgung ein. Eine vergleichbare Bedeutung haben niedere Alkene wie Ethylen Propylen Produktion von Verbrauchsgütern. In einer Gesellschaft Nach‐Erdöl‐Zeit wird die Kraftstoffen Alkenen auf alternative Quellen Biomasse, Kohle, Erdgas CO 2 angewiesen sein. Die Umwandlung Methanol Kohlenwasserstoffe, bekannt als Methanol‐to‐...
Four 3D 10-ring zeolites, IM-5, TNU-9, ZSM-11 and ZSM-5, with Si/Al = 14-24 crystal sizes below 2 microns, were tested as catalysts for the methanol to hydrocarbons reaction (MTH) at atmospheric pressure, 350 °C WHSV 9 h(-1). All gave initially full conversion, showed strikingly similar effluent product selectivities. However, their life-time duration differed significantly, decreased in order: > ZSM-5 ≫ TNU-9 IM-5. A main difference between two groups of stability behaviour was size...
The ability of a zeolitic catalyst to dehydrate methanol dimethyl ether affects deactivation and product distribution during the methanol-to-hydrocarbons (MTH) reaction.
The catalytic conversion of methanol (MeOH) and dimethyl ether (DME) into fuels chemicals over zeolites (MTH process) is industrially emerging as an alternative route to conventional oil-derived processes. After 40 years research, a detailed mechanistic understanding the intricate reaction network still not fully accomplished. overall described two competitive cycles, dominated by alkenes arenes, which are methylated cracked or dealkylated form effluent products. Herein, we present isobutene...
Zeolite ZSM-5 is one of the most widely used zeolites, in particular heterogeneous catalysis. This work investigates incorporation Al silica framework monoclinic and speciation during steam treatment for four samples with different Si/Al ratios, using ultrahigh field 27Al NMR (22.3 T), 29Si NMR, X-ray diffraction, IR spectroscopy. MQMAS at 22.3 T allows identification quantification 10 distinct tetrahedral resonances which are assigned to crystallographic sites by their average T–O–T angles,...