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Journal articles on the topic 'Catalytic cycles'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Zeravcic, Zorana, and Michael P. Brenner. "Spontaneous emergence of catalytic cycles with colloidal spheres." Proceedings of the National Academy of Sciences 114, no. 17 (April 10, 2017): 4342–47. http://dx.doi.org/10.1073/pnas.1611959114.

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Colloidal particles endowed with specific time-dependent interactions are a promising route for realizing artificial materials that have the properties of living ones. Previous work has demonstrated how this system can give rise to self-replication. Here, we introduce the process of colloidal catalysis, in which clusters of particles catalyze the creation of other clusters through templating reactions. Surprisingly, we find that simple templating rules generically lead to the production of huge numbers of clusters. The templating reactions among this sea of clusters give rise to an exponentially growing catalytic cycle, a specific realization of Dyson’s notion of an exponentially growing metabolism. We demonstrate this behavior with a fixed set of interactions between particles chosen to allow a catalysis of a specific six-particle cluster from a specific seven-particle cluster, yet giving rise to the catalytic production of a sea of clusters of sizes between 2 and 11 particles. The fact that an exponentially growing cycle emerges naturally from such a simple scheme demonstrates that the emergence of exponentially growing metabolisms could be simpler than previously imagined.

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2

Varfolomeev, Sergei D., Igor A. Gariev, and Igor' V. Uporov. "Catalytic sites of hydrolases: structures and catalytic cycles." Russian Chemical Reviews 74, no. 1 (January 31, 2005): 61–76. http://dx.doi.org/10.1070/rc2005v074n01abeh001159.

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3

Boudart, M. "Adsorption assisted desorption in catalytic cycles." Journal of Molecular Catalysis A: Chemical 141, no. 1-3 (May 6, 1999): 1–7. http://dx.doi.org/10.1016/s1381-1169(98)00244-1.

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4

Kozuch, Sebastian, and Jan M. L. Martin. "“Turning Over” Definitions in Catalytic Cycles." ACS Catalysis 2, no. 12 (November 20, 2012): 2787–94. http://dx.doi.org/10.1021/cs3005264.

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5

Uhe, Andreas, Sebastian Kozuch, and Sason Shaik. "Automatic analysis of computed catalytic cycles." Journal of Computational Chemistry 32, no. 5 (November 12, 2010): 978–85. http://dx.doi.org/10.1002/jcc.21669.

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6

Sinibaldi, Arianna, Valeria Nori, Andrea Baschieri, Francesco Fini, Antonio Arcadi, and Armando Carlone. "Organocatalysis and Beyond: Activating Reactions with Two Catalytic Species." Catalysts 9, no. 11 (November 6, 2019): 928. http://dx.doi.org/10.3390/catal9110928.

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Since the beginning of the millennium, organocatalysis has been gaining a predominant role in asymmetric synthesis and it is, nowadays, a foundation of catalysis. Synergistic catalysis, combining two or more different catalytic cycles acting in concert, exploits the vast knowledge acquired in organocatalysis and other fields to perform reactions that would be otherwise impossible. Merging organocatalysis with photo-, metallo- and organocatalysis itself, researchers have ingeniously devised a range of activations. This feature review, focusing on selected synergistic catalytic approaches, aims to provide a flavor of the creativity and innovation in the area, showing ground-breaking examples of organocatalysts, such as proline derivatives, hydrogen bond-mediated, Cinchona alkaloids or phosphoric acids catalysts, which work cooperatively with different catalytic partners.

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7

Grishchenko, Liudmyla, Natalia S. Novychenko, Igor Matushko, Alexander N. Zaderko, Galyna G. Tsapyuk, Oleksandr V. Mischanchuk, Vitaliy E. Diyuk, and Vladyslav V. Lisnyak. "Catalytic efficiency of activated carbon functionalized with phosphorus-containing groups in 2-propanol dehydration." French-Ukrainian Journal of Chemistry 7, no. 1 (2019): 46–56. http://dx.doi.org/10.17721/fujcv7i1p46-56.

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The functionalization of activated carbon (AC) by P-containing groups was conducted, and their thermal desorption was studied. Depending on the used method, the functionalized AC contains 0.5–1.45 mmol/g of acidic groups acting in catalytic 2-propanol dehydration. All catalysts showed 100% conversion of 2-propanol to propylene. The catalytic activity does not change with time under isothermal conditions and during their repeated use in catalysis, for 3 cycles of heating-cooling. In fact, the yield of propylene remains stable; it does not decrease with each cycle. Preliminary oxidation with nitric acid causes a small increase in the catalytic activity.

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8

Kim, Byungjun, Yongjae Kim, and Sarah Yunmi Lee. "Stereoselective Michael Additions of Arylacetic Acid Derivatives by Asymmetric Organocatalysis." Synlett 33, no. 07 (January 5, 2022): 609–16. http://dx.doi.org/10.1055/s-0041-1737323.

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AbstractBecause of the versatility of chiral 1,5-dicarbonyl structural motifs, the development of stereoselective Michael additions of arylacetic acid derivatives to electron-deficient alkenes is an important challenge. Over recent decades, an array of enantio- and diastereoselective methods of this type have been developed through the use of chiral organocatalysts. In this article, three distinct strategies in this research area are highlighted. Catalytic generation of either a chiral iminium electrophile (iminium catalysis) or a chiral enolate nucleophile (Lewis base catalysis) has allowed the efficient construction of stereogenic C–C bonds. We also introduce a synergistic catalytic approach involving the merger of these two catalytic cycles that provides selective access to all four stereoisomers of products with vicinal stereocenters.1 Introduction2 Iminium Catalysis3 Lewis Base Catalysis4 Synergistic Organocatalysis5 Summary

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9

Hunt, Patricia A. "Organolanthanide mediated catalytic cycles: a computational perspective." Dalton Transactions, no. 18 (2007): 1743. http://dx.doi.org/10.1039/b700876g.

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10

Al-Shawi, Marwan K. "Catalytic and transport cycles of ABC exporters." Essays in Biochemistry 50 (September 7, 2011): 63–83. http://dx.doi.org/10.1042/bse0500063.

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ABC (ATP-binding cassette) transporters are arguably the most important family of ATP-driven transporters in biology. Despite considerable effort and advances in determining the structures and physiology of these transporters, their fundamental molecular mechanisms remain elusive and highly controversial. How does ATP hydrolysis by ABC transporters drive their transport function? Part of the problem in answering this question appears to be a perceived need to formulate a universal mechanism. Although it has been generally hoped and assumed that the whole superfamily of ABC transporters would exhibit similar conserved mechanisms, this is proving not to be the case. Structural considerations alone suggest that there are three overall types of coupling mechanisms related to ABC exporters, small ABC importers and large ABC importers. Biochemical and biophysical characterization leads us to the conclusion that, even within these three classes, the catalytic and transport mechanisms are not fully conserved, but continue to evolve. ABC transporters also exhibit unusual characteristics not observed in other primary transporters, such as uncoupled basal ATPase activity, that severely complicate mechanistic studies by established methods. In this chapter, I review these issues as related to ABC exporters in particular. A consensus view has emerged that ABC exporters follow alternating-access switch transport mechanisms. However, some biochemical data suggest that alternating catalytic site transport mechanisms are more appropriate for fully symmetrical ABC exporters. Heterodimeric and asymmetrical ABC exporters appear to conform to simple alternating-access-type mechanisms.

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11

Boudart, M., and G. Dj�ga-Mariadassou. "Kinetic coupling in and between catalytic cycles." Catalysis Letters 29, no. 1-2 (1994): 7–13. http://dx.doi.org/10.1007/bf00814246.

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12

Díaz-López, José Antonio, Jordi Guilera, Martí Biset-Peiró, Dan Enache, Gordon Kelly, and Teresa Andreu. "Passivation of Co/Al2O3 Catalyst by Atomic Layer Deposition to Reduce Deactivation in the Fischer–Tropsch Synthesis." Catalysts 11, no. 6 (June 14, 2021): 732. http://dx.doi.org/10.3390/catal11060732.

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The present work explores the technical feasibility of passivating a Co/γ-Al2O3 catalyst by atomic layer deposition (ALD) to reduce deactivation rate during Fischer–Tropsch synthesis (FTS). Three samples of the reference catalyst were passivated using different numbers of ALD cycles (3, 6 and 10). Characterization results revealed that a shell of the passivating agent (Al2O3) grew around catalyst particles. This shell did not affect the properties of passivated samples below 10 cycles, in which catalyst reduction was hindered. Catalytic tests at 50% CO conversion evidenced that 3 and 6 ALD cycles increased catalyst stability without significantly affecting the catalytic performance, whereas 10 cycles caused blockage of the active phase that led to a strong decrease of catalytic activity. Catalyst deactivation modelling and tests at 60% CO conversion served to conclude that 3 to 6 ALD cycles reduced Co/γ-Al2O3 deactivation, so that the technical feasibility of this technique was proven in FTS.

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13

Lynch, David T. "Forced cycling of catalytic reactors: Number of cycles to reach cycle invariance." Canadian Journal of Chemical Engineering 64, no. 6 (December 1986): 1035–38. http://dx.doi.org/10.1002/cjce.5450640625.

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14

Zhu, Bo, Li-Kai Yan, Yun Geng, Hang Ren, Wei Guan, and Zhong-Min Su. "IrIII/NiII-Metallaphotoredox catalysis: the oxidation state modulation mechanism versus the radical mechanism." Chemical Communications 54, no. 47 (2018): 5968–71. http://dx.doi.org/10.1039/c8cc03550d.

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An oxidation state modulation mechanism, merging oxidative quenching (Ir^III–*Ir^III–Ir^IV–Ir^III) and nickel catalytic (Ni^II–Ni^I–Ni^III–Ni^I–Ni^II) cycles, is disclosed for Ir/Ni-metallaphotoredox catalysis.

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15

Jain, Mahendra Kumar, Bao-Zhu Yu, Michael H. Gelb, and Otto G. Berg. "Assay of phospholipases A2and their inhibitors by kinetic analysis in the scooting mode." Mediators of Inflammation 1, no. 2 (1992): 85–100. http://dx.doi.org/10.1155/s0962935192000164.

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Several cellular processes are regulated by interfacial catalysis on biomembrane surfaces. Phospholipases A2(PLA2) are interesting not only as prototypes for interfacial catalysis, but also because they mobilize precursors for the biosynthesis of eicosanoids and platelet activating factor, and these agents ultimately control a wide range of secretory and inflammatory processes. Since PLA2carry out their catalytic function at membrane surfaces, the kinetics of these enzymes depends on what the enzyme ‘sees’ at the interface, and thus the observed rate is profoundly influenced by the organization and dynamics of the lipidwater interface (‘quality of the interface’). In this review we elaborate the advantages of monitoring interfacial catalysis in the scooting mode, that is, under the conditions where the enzyme remains bound to vesicles for several thousand catalytic turnover cycles. Such a highly processive catalytic turnover in the scooting mode is useful for a rigorous and quantitative characterization of the kinetics of interfacial catalysis. This analysis is now extended to provide insights into designing strategy for PLA2assays and screens for their inhibitors.

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16

Hatamifard, Arezo, Mahmoud Nasrollahzadeh, and S. Mohammad Sajadi. "Biosynthesis, characterization and catalytic activity of an Ag/zeolite nanocomposite for base- and ligand-free oxidative hydroxylation of phenylboronic acid and reduction of a variety of dyes at room temperature." New Journal of Chemistry 40, no. 3 (2016): 2501–13. http://dx.doi.org/10.1039/c5nj02909k.

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17

Dimroth, Peter, Christoph von Ballmoos, and T. Meier. "Catalytic and mechanical cycles in F‐ATP synthases." EMBO reports 7, no. 3 (March 2006): 276–82. http://dx.doi.org/10.1038/sj.embor.7400646.

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18

Lente, Gábor. "Comment on “‘Turning Over’ Definitions in Catalytic Cycles”." ACS Catalysis 3, no. 3 (February 7, 2013): 381–82. http://dx.doi.org/10.1021/cs300846b.

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19

McFarlane, James, Brett Henderson, Sofia Donnecke, and J. Scott McIndoe. "An Information-Rich Graphical Representation of Catalytic Cycles." Organometallics 38, no. 21 (October 24, 2019): 4051–53. http://dx.doi.org/10.1021/acs.organomet.9b00563.

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20

Solel, Ephrath, Naziha Tarannam, and Sebastian Kozuch. "Catalysis: energy is the measure of all things." Chemical Communications 55, no. 37 (2019): 5306–22. http://dx.doi.org/10.1039/c9cc00754g.

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21

Yang, Bo, Kamal Sharkas, Laura Gagliardi, and Donald G. Truhlar. "The effects of active site and support on hydrogen elimination over transition-metal-functionalized yttria-decorated metal–organic frameworks." Catalysis Science & Technology 9, no. 24 (2019): 7003–15. http://dx.doi.org/10.1039/c9cy01069f.

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Transition-metal catalysts supported on a metal–organic framework have been screened computationally to reveal the best catalytic candidates for hydrogen elimination reactions, which are critical in many catalytic cycles.

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22

Andrade, Marta A., and Luísa M. D. R. S. Martins. "Sustainability in Catalytic Cyclohexane Oxidation: The Contribution of Porous Support Materials." Catalysts 10, no. 1 (December 18, 2019): 2. http://dx.doi.org/10.3390/catal10010002.

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The development of green and sustainable protocols for synthetic routes is a growing area of research in chemistry worldwide. The development of sustainable processes and products through innovative catalytic materials and technologies, that allow a better use of resources, is undoubtedly a very important issue facing research chemists today. Environmentally and economically advanced catalytic processes for selective alkane oxidations reactions, as is the case of cyclohexane oxidation, are now focused on catalysts’ stability and their reuse, intending to overcome the drawbacks posed by current homogeneous systems. The aim of this short review is to highlight recent contributions in heterogeneous catalysis regarding porous support materials to be applied to cyclohexane oxidation reaction. Different classes of porous materials are covered, from carbon nanomaterials to zeolites, mesoporous silicas, and metal organic frameworks. The role performed by the materials to be used as supports towards an enhancement of the activity/selectivity of the catalytic materials and the ability of recycling and reuse in consecutive catalytic cycles is highlighted.

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23

Stößer, T., T. T. D. Chen, Y. Zhu, and C. K. Williams. "‘Switch’ catalysis: from monomer mixtures to sequence-controlled block copolymers." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, no. 2110 (November 27, 2017): 20170066. http://dx.doi.org/10.1098/rsta.2017.0066.

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A ‘Switch’ catalysis method is reviewed whereby a single catalyst is switched between ring-opening polymerization and ring-opening copolymerization cycles. It allows the efficient synthesis of block copolymers from mixtures of lactones, epoxides, anhydrides and carbon dioxide. In order to use and further develop such ‘Switch’ catalysis, it is important to understand how to monitor the catalysis and characterize the product block copolymers. Here, a step-by-step guide to both the catalysis and the identification of block copolymers is presented. This article is part of a discussion meeting issue ‘Providing sustainable catalytic solutions for a rapidly changing world’.

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24

Faggiano, Antonio, Maria Ricciardi, and Antonio Proto. "Catalytic Routes to Produce Polyphenolic Esters (PEs) from Biomass Feedstocks." Catalysts 12, no. 4 (April 18, 2022): 447. http://dx.doi.org/10.3390/catal12040447.

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Polyphenolic esters (PEs) are valuable chemical compounds that display a wide spectrum of activities (e.g., anti-oxidative effects). As a result, their production through catalytic routes is an attractive field of research. The present review aims to discuss recent studies from the literature regarding the catalytic production of PEs from biomass feedstocks, namely, naturally occurred polyphenolic compounds. Several synthetic approaches are reported in the literature, mainly bio-catalysis and to a lesser extent acid catalysis. Immobilized lipases (e.g., Novozym 435) are the preferred enzymes thanks to their high reactivity, selectivity and reusability. Acid catalysis is principally investigated for the esterification of polyphenolic acids with fatty alcohols and/or glycerol, using both homogeneous (p-toluensulfonic acid, sulfonic acid and ionic liquids) and heterogeneous (strongly acidic cation exchange resins) catalysts. Based on the reviewed publications, we propose some suggestions to improve the synthesis of PEs with the aim of increasing the greenness of the overall production process. In fact, much more attention should be paid to the use of new and efficient acid catalysts and their reuse for multiple reaction cycles.

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25

Vieira, Eduardo Guimarães, Rafael Oliveira Silva, Alexandre Gonçalves Dal-Bó, Tiago Elias Allievi Frizon, and Newton Luiz Dias Filho. "Syntheses and catalytic activities of new metallodendritic catalysts." New Journal of Chemistry 40, no. 11 (2016): 9403–14. http://dx.doi.org/10.1039/c6nj01629d.

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26

Larin, I. K. "Chain Lengths of Haloid Catalytic Cycles of Ozone Destruction." Izvestiya, Atmospheric and Oceanic Physics 58, no. 4 (August 2022): 391–400. http://dx.doi.org/10.1134/s0001433822040089.

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27

Schwarz, Patrick S., Marta Tena-Solsona, Kun Dai, and Job Boekhoven. "Carbodiimide-fueled catalytic reaction cycles to regulate supramolecular processes." Chemical Communications 58, no. 9 (2022): 1284–97. http://dx.doi.org/10.1039/d1cc06428b.

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A challenge in supramolecular chemistry is to control self-assembly out-of-equilibrium. Towards that goal, chemically fueled self-assembly has emerged as a powerful tool. We review the progress in assembly fueled by the hydration of carbodiimides.

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28

Kozuch, Sebastian, and Sason Shaik. "How to Conceptualize Catalytic Cycles? The Energetic Span Model." Accounts of Chemical Research 44, no. 2 (February 15, 2011): 101–10. http://dx.doi.org/10.1021/ar1000956.

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29

Bayram, Mustafa. "Derivation of conservation relationships for catalytic cycles using MAPLE." Applied Mathematics and Computation 160, no. 1 (January 2005): 189–95. http://dx.doi.org/10.1016/j.amc.2003.10.036.

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30

Boudart, Michel. "ChemInform Abstract: Kinetic Coupling in and Between Catalytic Cycles." ChemInform 30, no. 45 (June 12, 2010): no. http://dx.doi.org/10.1002/chin.199945341.

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31

Meazza, Marta, Mark E. Light, Andrea Mazzanti, and Ramon Rios. "Synergistic catalysis: cis-cyclopropanation of benzoxazoles." Chemical Science 7, no. 2 (2016): 984–88. http://dx.doi.org/10.1039/c5sc03597j.

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32

Leng, Xiaonan, Dantong Zhou, Tong Gao, Zhi Chen, and Qiuming Gao. "Catalytic CO Oxidation over Au Nanoparticles Loaded Nanoporous Nickel Phosphate Composite." Journal of Nanomaterials 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/528906.

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Au/nickel phosphate-5 (Au/VSB-5) composite with the noble metal loading amount of 1.43 wt.% is prepared by using microporous VSB-5 nanocrystals as the support. Carbon monoxide (CO) oxidation reaction is carried out over the sample with several catalytic cycles. Complete conversion of CO is achieved at 238°C over the catalyst at the first catalytic cycle. The catalytic activity improved greatly at the second cycle with the complete conversion fulfilled at 198°C and preserved for the other cycles. A series of experiments such as X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-vis) spectroscopy, and X-ray photoelectron spectroscopy (XPS) are carried out to characterize the catalysts before and after the reaction to study the factors influencing this promotion at the second cycle.

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33

Lupaşcu, T., M. Ciobanu, V. Boţan, and A. Nistor. "Catalytic Oxidation of Methylene Blue." Chemistry Journal of Moldova 5, no. 2 (December 2010): 37–40. http://dx.doi.org/10.19261/cjm.2010.05(2).04.

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The intact activated carbon CAN-8, obtained from nutshells by activation with water vapours, in the presence of oxygen and at relatively low temperatures, possesses catalytic activity, caused by the presence of alkaline functional groups on its surface, as well as by the formation, in these experimental conditions, of the OH radical, which has a high oxidation potential. After 25 cycles of the process of methylene blue oxidation, the data of chromatographic analyses indicate the presence of three organic components in the solution.

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34

Pica, Monica, Silvia Calzuola, Anna Donnadio, Pier Gentili, Morena Nocchetti, and Mario Casciola. "De-Ethylation and Cleavage of Rhodamine B by a Zirconium Phosphate/Silver Bromide Composite Photocatalyst." Catalysts 9, no. 1 (December 21, 2018): 3. http://dx.doi.org/10.3390/catal9010003.

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A composite heterogeneous photocatalyst based on silver bromide was prepared by a reaction of silver exchanged zirconium phosphate (ZrP) and HBr. The ZrP/AgBr composite containing 53 wt% AgBr was tested in the photocatalytic degradation of Rhodamine B (RhB) and exhibited higher catalytic activity with respect to pure AgBr. As a matter of fact, the time needed to achieve a percentage of chromophore cleavage of about 90% was 3 min for the composite versus the 30 min needed for pure AgBr. The ZrP/AgBr composite turned out to be stable for at least three consecutive cycles. The UV-Vis spectra of the RhB solution, recorded at different irradiation times, were also decomposed and the concentration of the species formed by de-ethylation and cleavage processes during photocatalysis were calculated; the data obtained for the AgBr-based catalysis were also compared with those for the AgCl-based catalysis, and the degradation mechanism was suggested for both catalytic systems.

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35

Fakeeha, Anis, Siham Barama, Ahmed Ibrahim, Raja-Lafi Al-Otaibi, Akila Barama, Ahmed Abasaeed, and Ahmed Al-Fatesh. "In Situ Regeneration of Alumina-Supported Cobalt–Iron Catalysts for Hydrogen Production by Catalytic Methane Decomposition." Catalysts 8, no. 11 (November 21, 2018): 567. http://dx.doi.org/10.3390/catal8110567.

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A novel approach to the in situ regeneration of a spent alumina-supported cobalt–iron catalyst for catalytic methane decomposition is reported in this work. The spent catalyst was obtained after testing fresh catalyst in catalytic methane decomposition reaction during 90 min. The regeneration evaluated the effect of forced periodic cycling; the cycles of regeneration were performed in situ at 700 °C under diluted O2 gasifying agent (10% O2/N2), followed by inert treatment under N2. The obtained regenerated catalysts at different cycles were tested again in catalytic methane decomposition reaction. Fresh, spent, and spent/regenerated materials were characterized using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), laser Raman spectroscopy (LRS), N2-physisorption, H2-temperature programmed reduction (H2-TPR), thermogravimetric analysis (TGA), and atomic absorption spectroscopy (AAS). The comparison of transmission electron microscope and X-ray powder diffraction characterizations of spent and spent/regenerated catalysts showed the formation of a significant amount of carbon on the surface with a densification of catalyst particles after each catalytic methane decomposition reaction preceded by regeneration. The activity results confirm that the methane decomposition after regeneration cycles leads to a permanent deactivation of catalysts certainly provoked by the coke deposition. Indeed, it is likely that some active iron sites cannot be regenerated totally despite the forced periodic cycling.

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Mirante, Fátima, Ricardo F. Mendes, Rui G. Faria, Luís Cunha-Silva, Filipe A. Almeida Paz, and Salete S. Balula. "Membrane-Supported Layered Coordination Polymer as an Advanced Sustainable Catalyst for Desulfurization." Molecules 26, no. 9 (April 21, 2021): 2404. http://dx.doi.org/10.3390/molecules26092404.

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The application of a catalytic membrane in the oxidative desulfurization of a multicomponent model diesel formed by most refractory sulfur compounds present in fuel is reported here for the first time. The catalytic membrane was prepared by the impregnation of the active lamellar [Gd(H4nmp)(H2O)2]Cl·2H2O (UAV-59) coordination polymer (CP) into a polymethyl methacrylate (PMMA, acrylic glass) supporting membrane. The use of the catalytic membrane in the liquid–liquid system instead of a powder catalyst arises as an enormous advantage associated with the facility of catalyst handling while avoiding catalyst mass loss. The optimization of various parameters allowed to achieve a near complete desulfurization after 3 h under sustainable conditions, i.e., using an aqueous H2O2 as oxidant and an ionic liquid as extraction solvent ([BMIM]PF6, 1:0.5 ratio diesel:[BMIM]PF6). The performance of the catalytic membrane and of the powdered UAV-59 catalyst was comparable, with the advantage that the former could be recycled successfully for a higher number of desulfurization cycles without the need of washing and drying procedures between reaction cycles, turning the catalytic membrane process more cost-efficient and suitable for future industrial application.

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37

Yan, Xiuli, and Xinzheng Yang. "Mechanistic insights into the iridium catalysed hydrogenation of ethyl acetate to ethanol: a DFT study." Dalton Transactions 47, no. 30 (2018): 10172–78. http://dx.doi.org/10.1039/c8dt02401d.

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38

Thapplee, Montri, Chadaporn Krutpijit, Piyasan Praserthdam, and ฺีBunjerd Jongsomjit. "Modification of acid on beta zeolite catalysts by ion-exchange method for ethanol dehydration to diethyl ether." Mediterranean Journal of Chemistry 10, no. 7 (August 3, 2020): 697. http://dx.doi.org/10.13171/mjc107020081481bj.

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<p class="Mabstract">The catalytic ethanol dehydration to diethyl ether (DEE) over the synthesized beta zeolite (BEA) with different acidity on catalysts having Na and mixed Na-H forms was studied. The Na form of BEA catalyst was synthesized via the hydrothermal process, including non-calcined (Na-BEA_N) and calcined (Na-BEA_C) catalysts. The Na-BEA_C catalyst was successively used in the synthesis of different mixed Na-H forms under the ion-exchange method using the ammonium nitrate solution at 70°C for 2 h/cycle. In the present study, two different cycles were chosen, including one cycle (M-BEA_1) and four cycles (M-BEA_4) to compare the amount of acidity on catalysts. The results indicated that the M-BEA_1 catalyst exhibited a large surface area and contained the highest moderate acid site, which strongly affected the optimal catalytic activity at low temperature (<250°C) with ethanol conversion of 74.6% and DEE yield of 27.3%. However, the increased number of ion-exchange cycles had not shown remarkable effects on catalytic activity due to low surface area and moderate acidity.<strong></strong></p>

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39

Downing, C. A., A. A. Sokol, and C. R. A. Catlow. "The reactivity of CO2 and H2 at trapped electron sites at an oxide surface." Phys. Chem. Chem. Phys. 16, no. 39 (2014): 21153–56. http://dx.doi.org/10.1039/c4cp02610a.

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40

To Anh, Tuong, Trang Nguyen Thi Thuy, Anh Nguyen Thai, and Nam Phan Thanh Son. "Cu2(BDC)2DABCO as an efficient heterogeneous catalyst for the oxidative C-N coupling reaction between amides and unactivated alkanes." Vietnam Journal of Catalysis and Adsorption 9, no. 1 (April 30, 2020): 67–72. http://dx.doi.org/10.51316/jca.2020.011.

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A copper-organic framework Cu2(BDC)2DABCO was synthesized, and used as a recyclable heterogeneous catalyst for C-N coupling reaction between benzamide and cyclohexane. 94% yield of N-cyclohexylbenzamide was achieved under the optimized condition. The copper-organic framework catalyst was truly heterogeneous and could be used at least 4 cycles without degradation of catalytic performance. To the best of our knowledge, the amidation of unactivated alkanes by benzamides via direct oxidative C-N coupling was previously performed under heterogeneous catalysis conditions but very rare.

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41

Xu, Dongdong, Xiaotian Qi, Meng Duan, Zhaoyuan Yu, Lei Zhu, Chunhui Shan, Xiaoyu Yue, Ruopeng Bai, and Yu Lan. "Thiolate–palladium(iv) or sulfonium–palladate(0)? A theoretical study on the mechanism of palladium-catalyzed C–S bond formation reactions." Organic Chemistry Frontiers 4, no. 6 (2017): 943–50. http://dx.doi.org/10.1039/c6qo00841k.

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Qun, W., Z. Jingnan, L. Hong, L. Mengling, L. Xiaohui, Y. Zhichao, H. Tao, and W. Pengyu. "Mesoporous TiO2/carbon catalytic ozonation for degradation of p-chloronitrobenzene." Water Science and Technology 80, no. 5 (September 1, 2019): 902–10. http://dx.doi.org/10.2166/wst.2019.331.

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Abstract In this study, a mesoporous TiO2/carbon catalyst (TiO2/C) was prepared by a facile impregnation-carbonization approach to catalyze ozonation of p-chloronitrobenzene (p-CNB). The catalyst was well characterized and the catalytic efficiency under various conditions was systematically evaluated. TiO2/C has a disordered mesostructure with a high specific surface area. 92.8% of p-CNB (2 μmol/L) can be degraded within 20 min in the TiO2/C/O3 system in the presence of 1 mg/L O3, 100 mg/L catalyst, at pH = 5. Based on the evaluation of the effect of basic parameters, it could be deduced that the removal of p-CNB relied on the synthetic effect of catalysis by TiO2/C and the autocatalytic induction of p-CNB. The removal efficiency of p-CNB, the structure change and the leaching of Ti ions were also evaluated in five cycles, indicating TiO2/C is stable and recyclable for catalytic ozonation in water treatment.

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Gorunova, O. N., Yu K. Grishin, M. M. Ilyin, K. A. Kochetkov, A. V. Churakov, L. G. Kuz´mina, and V. V. Dunina. "Enantioselective catalysis of Suzuki reaction with planar-chiral CN-palladacycles: competition of two catalytic cycles." Russian Chemical Bulletin 66, no. 2 (February 2017): 282–92. http://dx.doi.org/10.1007/s11172-017-1729-4.

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Massardo, A. F., and B. Bosio. "Assessment of Molten Carbonate Fuel Cell Models and Integration With Gas and Steam Cycles." Journal of Engineering for Gas Turbines and Power 124, no. 1 (February 1, 2001): 103–9. http://dx.doi.org/10.1115/1.1398551.

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The aim of this work is to investigate the performance of molten carbonate fuel cells (MCFCs), with external sensible heat reformer and gas turbine/steam turbine (GT/ST) combined cycles. The analysis of these MCFC-GT/ST combined cycles has been carried out using the thermo economic modular program (TEMP) modified to allow MCFC, external sensible heat reformer, and catalytic burner performance to be carefully taken into account. The code has been verified through the use of a detailed MCFC model and of the data available for an existing MCFC unit. The thermodynamic and exergy analysis of a number of MCFC combined cycles is presented and discussed, taking into account the influence of technological constraints, also evaluated with the sophisticated model, and the influence of the post-combustion of the fuel directly in the external catalytic burner. The results are presented and discussed in depth.

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Leyva-Pérez, Antonio, Antonio Doménech, Saud I. Al-Resayes, and Avelino Corma. "Gold Redox Catalytic Cycles for the Oxidative Coupling of Alkynes." ACS Catalysis 2, no. 1 (December 13, 2011): 121–26. http://dx.doi.org/10.1021/cs200532c.

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Kozuch, Sebastian. "Reply to Comment on “‘Turning Over’ Definitions in Catalytic Cycles”." ACS Catalysis 3, no. 3 (February 6, 2013): 380. http://dx.doi.org/10.1021/cs4000415.

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Chen, Yu, and Wolfgang Maret. "Catalytic selenols couple the redox cycles of metallothionein and glutathione." European Journal of Biochemistry 268, no. 11 (June 1, 2001): 3346–53. http://dx.doi.org/10.1046/j.1432-1327.2001.02250.x.

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Murzin, Dmitry Yu. "On the topological representation of catalytic cycles with nonlinear steps." Reaction Kinetics and Catalysis Letters 90, no. 2 (April 2007): 225–32. http://dx.doi.org/10.1007/s11144-007-5018-3.

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Lugovski, A. A., G. A. Gusakov, M. P. Samtsov, V. A. Parhomenko, and S. V. Adamchyk. "Modified ultradispersed diamonds based catalytic systems in cross-coupling reactions." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 57, no. 1 (February 10, 2021): 7–14. http://dx.doi.org/10.29235/1561-8331-2021-57-1-7-14.

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Methods for preparation of nanocomposites of modified detonation nanodiamonds (DND) with metallic palladium have been developed and their catalytic activity in the Suzuki-Miyaura cross-coupling reaction in various reaction media has been studied. Methods for the regeneration of palladium-containing nanocomposites from the reaction mixture have been developed. The high catalytic activity of nanocomposites is confirmed by kinetic analysis based on the results of chromatographic analysis of the reaction mixture and is comparable to the literature data about similar catalytic systems. Regenerated nanocomposites showed the retention of catalytic activity for 3 consecutive cross-coupling cycles on model systems.

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Zhu, Fengfan, Guang Yang, Adam J. Zoll, Elena V. Rybak-Akimova, and Xinbao Zhu. "Manganese Catalysts with Tetradentate N-donor Pyridine-Appended Bipiperidine Ligands for Olefin Epoxidation Reactions: Ligand Electronic Effect and Mechanism." Catalysts 10, no. 3 (March 2, 2020): 285. http://dx.doi.org/10.3390/catal10030285.

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In this work, we described an electron-rich manganese mesoPYBP catalyst, Mn-SR-mesoPYBP(ClO4)2, by introducing electron-donating substituents on the mesoPYBP ligand. We optimized the catalytic performance in olefin epoxidation with H2O2 in the presence of acetic acid. The electron paramagnetic resonance (EPR) and cyclic voltammetry (CV) studies supported that an electronic effect could stabilize the high-valent intermediates in the catalytic cycles of the catalyst, which largely improved the catalytic performance and the reactivity of olefin epoxidation.

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