Gas-phase ruthenium clusters Ru(n)(+) (n=2-6) are employed as model systems to discover the origin of the outstanding performance of supported sub-nanometer ruthenium particles in the catalytic CO methanation reaction with relevance to the hydrogen feed-gas purification for advanced fuel-cell applications. Using ion-trap mass spectrometry in conjunction with first-principles density functional theory calculations three fundamental properties of these clusters are identified which determine the selectivity and catalytic activity: high reactivity toward CO in contrast to inertness in the reaction with CO2; promotion of cooperatively enhanced H2 coadsorption and dissociation on pre-formed ruthenium carbonyl clusters, that is, no CO poisoning occurs; and the presence of Ru-atom sites with a low number of metal-metal bonds, which are particularly active for H2 coadsorption and activation. Furthermore, comprehensive theoretical investigations provide mechanistic insight into the CO methanation reaction and discover a reaction route involving the formation of a formyl-type intermediate.
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http://dx.doi.org/10.1002/anie.201310134 | DOI Listing |
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December 2024
Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
The separation and purification of acetylene from the light hydrocarbon gas mixtures is considered as one of the most industrially challenging task for the production of fine chemicals. Though metal-organic frameworks (MOFs) are promising candidates for such separation and offer a cost and energy-efficient pathway, achieving the trade-off between sorption capacity and separation selectivity along with framework robustness is a daunting task and demands effective design. Herein, a new 3D chemically stable MOF, IITKGP-24 (stable over a wide range of aqueous pH solution, pH = 2-12) is developed, displaying excellent separation selectivity of 13.
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January 2025
Department of Heterogeneous Catalysis, Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45740, Mülheim an der Ruhr.
Electric plasma assisted pyrolysis of methane represents a highly promising greener alternative to produce ethylene from biogas and renewable energies compared to conventional steam cracking of naphtha. The mediocre performance of typical Pd-Ag catalysts for the downstream purification of the substantially higher concentrated acetylene impurities (≥15 vol.-%) in those ethylene streams via selective hydrogenation is yet limiting economic interest.
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June 2023
Department of Physics, Indian Institute of Technology Jodhpur, Jodhpur, Rajasthan, 342037, India.
Air pollution is one of the top 5 risks causing chronic diseases according to WHO and airborne transmitted pathogens infection is a huge challenge in the current era. Long living pathogens and small size aerosols are not effectively dealt with by the available indoor air purifiers. In this work, a dielectric barrier discharge (DBD) based portable cold-plasma detergent in environment device is reported and its disinfection efficiency has been analyzed in the indoor environment of sizes up to 3 × 2.
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March 2022
Department of Petroleum Engineering, Faculty of Computing, Engineering & Technology, School of Engineering, Asia Pacific University of Technology, and Innovation, Kuala Lumpur 57000, Malaysia.
The challenges in developing high CO gas fields are governed by several factors such as reservoir condition, feed gas composition, operational pressure and temperature, and selection of appropriate technologies for bulk CO separation. Thus, in this work, we report an optimization study on the separation of CO from CH at high CO feed concentration over a functionalized mixed matrix membrane using a statistical tool, response surface methodology (RSM) statistical coupled with central composite design (CCD). The functionalized mixed matrix membrane containing NH-MIL-125 (Ti) and 6FDA-durene, fabricated in our previous study, was used to perform the separation performance under three operational parameters, namely, feed pressure, temperature, and CO feed concentration, ranging from 3.
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October 2021
Chemical and Biological Engineering Department, Colorado School of Mines, Golden, CO 80401, USA.
Palladium and palladium alloy membranes are superior materials for hydrogen purification, removal, or reaction processes. Sieverts' Law suggests that the flux of hydrogen through such membranes is proportional to the difference between the feed and permeate side partial pressures, each raised to the 0.5 power ( = 0.
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