Direct partial oxidation of methane into methanol is a cornerstone of catalysis. The stepped conversion of methane into methanol currently involves activation at high temperature and reaction with methane at decreased temperature, which limits applicability of the technique. The first implementation of copper-containing zeolites in the production of methanol directly from methane is reported, using molecular oxygen under isothermal conditions at 200 °C. Copper-exchanged zeolite is activated with oxygen, reacts with methane, and is subsequently extracted with steam in a repeated cyclic process. Methanol yield increases with methane pressure, enabling reactivity with less reactive oxidized copper species. It is possible to produce methanol over catalysts that were inactive in prior state of the art systems. Characterization of the activated catalyst at low temperature revealed that the active sites are small clusters of copper, and not necessarily di- or tricopper sites, indicating that catalysts can be designed with greater flexibility than formerly proposed.
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http://dx.doi.org/10.1002/anie.201511065 | DOI Listing |
Chem Rec
January 2025
Bioinspired & Biomimetic Inorganic Chemistry Laboratory, Department of Chemistry, National Institute of Technology Calicut, Kozhikode, Kerala, 673601, India.
Direct methane to methanol conversion is a dream reaction in industrial chemistry, which takes inspiration from the biological methanol production catalysed by methane monooxygenase enzymes (MMOs). Over the years, extensive studies have been conducted on this topic by bioengineering the MMOs, and tailoring methods to isolate the MMOs in the active form. Similarly, remarkable achievements have been noted in other methane activation strategies such as the use of heterogeneous catalysts or molecular catalysts.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
South China University of Technology, School of Chemistry and Chemical Engineering, Wushan St., 510640, Guangzhou, CHINA.
An inevitable overoxidation process is considered as one of the most challenging problems in the direct conversion of methane (CH4) to methanol (CH3OH), which is limited by the uncontrollable cracking of key intermediates. Herein, we have successfully constructed a photocatalyst, the Fe-doped ZnO hollow polyhedron (Fe/ZnOHP), for the highly selective photoconversion of CH4 to CH3OH under mild conditions. In-situ experiments and density functional theory calculations confirmed that the introduction of Fe was able to decrease the energy level of the O 2p orbital, which passivated the activity of lattice oxygen in ZnO nanocrystals.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Department of Chemical Engineering, Northeastern University, Boston, Massachusetts, 02115, USA.
Discovering electrocatalysts that can efficiently convert carbon dioxide (CO) to valuable fuels and feedstocks using excess renewable electricity is an emergent carbon-neutral technology. A single metal atom embedded in doped graphene, , single-atom catalyst (SAC), possesses high activity and selectivity for electrochemical CO reduction (COR) to CO, yet further reduction to hydrocarbons is challenging. Here, using density functional theory calculations, we investigate stability and reactivity of a broad SAC chemical space with various metal centers (3d transition metals) and dopants (2p dopants of B, N, O; 3p dopants of P, S) as electrocatalysts for COR to methane and methanol.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Institute of Applied Electrochemistry, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029 PR China. Electronic address:
The electrochemical activation and partial oxidation of methane are highly attractive to enable the direct conversion in a sustainable and decentralized way. Herein, we report an electrochemical system in a non-diaphragm electrochemical bath to convert CH to CHOH and CHCHOH at room temperature, in which VO·HO as the anodic catalyst to activate CH and an aprotic ionic liquid [BMIM]BF as supporting electrolyte to control superoxide radicals (O) as the main active oxygen species generated on cathode. As a result, methanol and ethanol were identified as the liquid products, and the superior methanol Faraday efficiency (FE) of 32.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Centre for Lasers & Photonics, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India.
Nonideality in a binary solvent mixture is manifested through anomalies in various physical properties like viscosity, dielectric constant, polarity, freezing point, boiling point, and so forth. Sometimes, such anomalies become much more prominent, leading to a synergistic behavior, where the physical property of the mixture is way different from its bulk counterparts. Various alcohols/chlorinated methane binary solvent mixtures show such a synergistic behavior.
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