Journal articles: 'Catalysis and Reaction Engineering'

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Tsotsis, Theodore T. "Reaction engineering and catalysis." Current Opinion in Chemical Engineering 1, no. 3 (August 2012): 269–71. http://dx.doi.org/10.1016/j.coche.2012.07.001.

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Bloh, Jonathan Z., and Roland Marschall. "Heterogeneous Photoredox Catalysis: Reactions, Materials, and Reaction Engineering." European Journal of Organic Chemistry 2017, no. 15 (March 10, 2017): 2085–94. http://dx.doi.org/10.1002/ejoc.201601591.

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Sial, Atif, Afzal Ahmed Dar, Yifan Li, and Chuanyi Wang. "Plasmon-Induced Semiconductor-Based Photo-Thermal Catalysis: Fundamentals, Critical Aspects, Design, and Applications." Photochem 2, no. 4 (October 2, 2022): 810–30. http://dx.doi.org/10.3390/photochem2040052.

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Photo-thermal catalysis is among the most effective alternative pathways used to perform chemical reactions under solar irradiation. The synergistic contributions of heat and light during photo-thermal catalytic processes can effectively improve reaction efficiency and alter design selectivity, even under operational instability. The present review focuses on the recent advances in photo-thermal-driven chemical reactions, basic physics behind the localized surface plasmon resonance (LSPR) formation and enhancement, pathways of charge carrier generation and transfer between plasmonic nanostructures and photo-thermal conversion, critical aspects influencing photo-thermal catalytic performance, tailored symmetry, and morphology engineering used to design efficient photo-thermal catalytic systems. By highlighting the multifield coupling benefits of plasmonic nanomaterials and semiconductor oxides, we summarized and discussed several recently developed photo-thermal catalysts and their catalytic performance in energy production (CO2 conversion and H2 dissociation), environmental protection (VOCs and dyes degradation), and organic compound synthesis (Olefins). Finally, the difficulties and future endeavors related to the design and engineering of photo-thermal catalysts were pointed out to draw the attention of researchers to this sustainable technology used for maximum solar energy utilization.

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Ball, Philip. "Catalysis: facing the future." National Science Review 2, no. 2 (April 24, 2015): 202–4. http://dx.doi.org/10.1093/nsr/nwv022.

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Abstract Most of the chemical reactions used to produce the molecules and materials that our societies need—for example, in the petrochemical and pharmaceutical industries, the synthesis of plastics and other materials, and the production of foods and drinks—make use of catalysts. These speed up the rate at which atoms and molecules rearrange themselves into new forms, and provide a degree of control over the shape and form of those rearrangements. Catalysts let us drive a chemical reaction in a selected direction, in preference to others that could occur. In this way they turn chemistry from crude cookery into a rational and precise form of molecular engineering. And always we can draw inspiration, and sometimes borrow tricks, from the delicate and precise catalytic processes that occur in nature, where enzymes carry out processes in aqueous solution and at mild temperatures and pressures that often we struggle to achieve with far more extreme conditions—such as the fixation of atmospheric nitrogen into useful forms. It is often claimed that this particular catalytic process—the Haber–Bosch process for converting nitrogen into ammonia, discovered just over a century ago—has, by making possible the synthesis of artificial fertilizers, had a greater effect on humankind than any other single chemical innovation. It is what allows us to feed the world. Yet while nature performs this reaction using soluble molecules (enzymes) as catalysts, the Haber–Bosch process uses powdered iron (plus some additives). The reactions between nitrogen and hydrogen take place on the surface of iron particles: this is so-called heterogeneous catalysis, involving surface chemistry, rather than the homogeneous catalysis of enzyme reactions, in which the catalysts are soluble molecules. Both homogeneous and heterogeneous catalysis are essential to the chemical industries. National Science Review spoke with two of the foremost practitioners of the latter field—Nobel laureate Gerhard Ertl of the Fritz Haber Institute in Berlin, Germany, and Avelino Corma of the Institute of Chemical Technology (ITQ) at the Polytechnic University of Valencia, Spain—about the current status of research in catalysis and prospects for the future.

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Mantilli, Luca, David Gérard, Sonya Torche, Céline Besnard, and Clément Mazet. "Highly enantioselective isomerization of primary allylic alcohols catalyzed by (P,N)-iridium complexes." Pure and Applied Chemistry 82, no. 7 (May 4, 2010): 1461–69. http://dx.doi.org/10.1351/pac-con-09-09-10.

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The catalytic asymmetric isomerization of allylic amines to enamines stands out as one of the most accomplished and well-studied reactions in asymmetric catalysis as illustrated by its industrial application. In contrast, the related asymmetric isomerization of primary allylic alcohols to the corresponding aldehydes still constitutes a significant challenge in organic synthesis. Herein, we show that under appropriate reaction conditions, iridium-hydride catalysts promote the isomerization of primary allylic alcohols under very mild reaction conditions. The best catalysts deliver the desired chiral aldehydes with unprecedented levels of enantioselectivity and good yields. Mechanistic hypotheses have been drawn based on preliminary investigations.

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Longwitz, Lars, and Thomas Werner. "Recent advances in catalytic Wittig-type reactions based on P(III)/P(V) redox cycling." Pure and Applied Chemistry 91, no. 1 (January 28, 2019): 95–102. http://dx.doi.org/10.1515/pac-2018-0920.

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Abstract Numerous organic transformations are based on the use of stoichiometric amounts of phosphorus reagents. The formation of phosphane oxides from phosphanes is usually the thermodynamic driving force for these reactions. The stoichiometric amounts of phosphane oxide which are formed as by-products often significantly hamper the product purification. Organophosphorus catalysis based on P(III)/P(V) redox cycling aims to address these problems. Herein we present our recent advances in developing catalytic Wittig-type reactions. More specifically, we reported our results on catalytic Wittig reactions based on readily available Bu3P=O as pre-catalyst as well as the first microwave-assisted version of this reaction and the first enantioselective catalytic Wittig reaction utilizing chiral phosphane catalysts. Further developments led to the implementation of catalytic base-free Wittig reactions yielding highly functionalized alkylidene and arylidene succinates.

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Dittmeyer, Roland, and Simon Kuhn. "Editorial overview: Reaction engineering and catalysis: Microreactor engineering." Current Opinion in Chemical Engineering 36 (June 2022): 100822. http://dx.doi.org/10.1016/j.coche.2022.100822.

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Keglevich, György, Nóra Zsuzsa Kiss, Réka Henyecz, and Zoltán Mucsi. "Microwave irradiation and catalysis in organophosphorus reactions." Pure and Applied Chemistry 91, no. 1 (January 28, 2019): 145–57. http://dx.doi.org/10.1515/pac-2018-0501.

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AbstractThe usual advantage of microwave (MW) assistance is making organic reactions faster and more efficient. In this article we present reaction types from organophosphorus chemistry, when MW-assisted transformations (e.g. the direct esterification and alkylating esterification of phosphinic acids) may be promoted by suitable catalysts, or vice versa, when a catalytic reaction is enhanced by MW irradiation (e.g. the Arbuzov reaction of aryl halides), and when catalysts may be omitted or simplified under MW irradiation as shown by the alkylation of active methylene containing P=O substrates/the Kabachnik–Fields reaction/deoxygenation of phosphine oxides, and the Hirao reaction, respectively.

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Lapkin, Alexei A. "Editorial overview- Reaction engineering and Catalysis: Green chemical engineering." Current Opinion in Chemical Engineering 26 (December 2019): A3. http://dx.doi.org/10.1016/j.coche.2019.12.002.

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Chen, Siyu, Zhanwei Xu, Jiayin Li, Jun Yang, Xuetao Shen, Ziwei Zhang, Hongkui Li, Wenyang Li, and Zhi Li. "Nanostructured transition-metal phthalocyanine complexes for catalytic oxygen reduction reaction." Nanotechnology 33, no. 18 (February 7, 2022): 182001. http://dx.doi.org/10.1088/1361-6528/ac4cef.

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Abstract Oxygen reduction reaction (ORR) plays a key role in the field of fuel cells. Efficient electrocatalysts for the ORR are important for fuel cells commercialization. Pt and its alloys are main active materials for ORR. However, their high cost and susceptibility to time-dependent drift hinders their applicability. Satisfactory catalytic activity of nanostructured transition metal phthalocyanine complexes (MPc) in ORR through the occurrence of molecular catalysis on the surface of MPc indicates their potential as a replacement material for precious-metal catalysts. Problems of MPc are analyzed on the basis of chemical structure and microstructure characteristics used in oxygen reduction catalysis, and the strategy for controlling the structure of MPc is proposed to improve the catalytic performance of ORR in this review.

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Ertl, Gerhard, Maria Zielińska, Małgorzata Rajfur, and Maria Wacławek. "Elementary steps in heterogeneous catalysis: The basis for environmental chemistry." Chemistry-Didactics-Ecology-Metrology 22, no. 1-2 (December 1, 2017): 11–41. http://dx.doi.org/10.1515/cdem-2017-0001.

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Abstract Catalysis is an alternative way for reaching an immediate formation of a product, because of a lower energy barrier (between the molecules and the catalysts). Heterogeneous catalysis comprises the acceleration of a chemical reaction through interaction of the molecules involved with the surface of a solid. It is a discipline, which involves all the different aspects of chemistry: inorganic and analytical chemistry in order to characterize the catalysts and the forms of these catalysts. The industrial chemistry puts all these things together to understand the solid chemical handling, chemical reaction and energy engineering and the heat and mass transfer in these catalytic processes. Very often there are more than one, but several products, then the role of the catalyst is not so much related to activity, but to selectivity. The underlying elementary steps can now be investigated down to the atomic scale as will be illustrated mainly with two examples: the oxidation of carbon monoxide (car exhaust catalyst) and the synthesis of ammonia (the basis for nitrogen fertilizer). There is a huge market for the catalysts themselves despite of their high costs. A large fraction is used for petroleum refineries, automotive and industrial cleaning processes. The catalytic processes is a wide field and there are still many problems concerning energy conservation and energy transformation, so there is much to do in the future.

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12

Coppens, Marc-Olivier, and Theodore T. Tsotsis. "New frontiers in reaction and catalysis engineering." Current Opinion in Chemical Engineering 2, no. 3 (August 2013): 302–3. http://dx.doi.org/10.1016/j.coche.2013.07.003.

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13

Guangqing, Zhang, Shenjun Qin, Li Zhen, Han Haiyan, Li Hui, and Tao Chang. "Coupling reaction of epoxide and carbon dioxide catalysed by alkali metal salts in the presence of ß-cyclodextrin derivatives." World Journal of Engineering 14, no. 2 (April 10, 2017): 159–64. http://dx.doi.org/10.1108/wje-12-2016-0172.

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Purpose This study aims to investigate the coupling reaction of epoxide and CO2 catalysed by alkali metal salts in the presence of ß-cyclodextrin (ß-CD) derivatives to generate cyclic carbonates at various conditions. Design/methodology/approach The coupling reaction was catalysed by alkali metal salts. The effects of the co-catalysts were investigated by using the conversion rate of raw materials. The affecting factors, such as reaction temperature, amount of the co-catalyst and reaction time, were explored. The possible mechanism of the coupling reaction was discussed. Findings Results showed that the structure of ß-CD is an important factor influencing the catalytic activity for the coupling reaction of epoxide with CO2. The catalytic system of 2,3,6-trimethyl-ß-CD with potassium iodide (KI) showed a high catalytic activity. The protocol was expanded to various epoxides, which provided the corresponding cyclic carbonates in excellent yields. The apparent decrease in the yields was not detected after four recycling times. Moreover, the mechanism for the synergetic effect of the catalyst was proposed. Originality/value The coupling reactions were achieved in the presence of different structure of ß-CD as co-catalysts. The affecting of substituent of ß-CD were investigated.

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Akbayeva, Dina Nauryzbaevna, Botagoz Sanatkyzy Bakirova, Gulziya Amangeldyevna Seilkhanova, and Helmut Sitzman. "Synthesis, Characterization, and Catalytic Activity of Palladium-polyvinylpyrrolidone Complex in Oxidation of Octene-1." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 3 (December 4, 2018): 560. http://dx.doi.org/10.9767/bcrec.13.3.1980.560-572.

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The metal complex catalysis with participation of unsaturated hydrocarbons gains great interest because of ecological aspect and a possibility of re-using of the catalyst. It has a number of advantages in comparison with a heterogeneous catalysis, such as high activity and selectivity, low temperatures of reaction and pressure. A palladium-polyvinylpyrrolidone complex was synthesized and characterized by potentiometry, conductometry, mass-, and IR-spectroscopy. The complex was tested for catalytic activity in reaction of octene-1 oxidation by inorganic oxidizers (KIO4, NaBrO3, Na2S2O8, K2S2O8) in dimethylsulfoxide or dimethylformamide under mild conditions. The reaction product was octanone-2, obtained in good yield (80-98 %) and characterized by gas chromatography and mass spectrometry. The catalysts can be easily recycled five consecutive runs without significant loss of catalytic efficiency. The use of different surface analysis techniques, such as: Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray spectroscopy (EDX), led to a better understanding of the polymer promoting effect. Copyright © 2018 BCREC Group. All rights reservedReceived: 18th December 2017; Revised: 6th August 2018; Accepted: 9th August 2018How to Cite: Akbayeva, D.N., Bakirova, B.S., Seilkhanova, G.A., Sitzmann, H. (2018). Synthesis, Characterization, and Catalytic Activity of Palladium-polyvinylpyrrolidone Complex in Oxidation of Octene-1. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 560- 572 (doi:10.9767/bcrec.13.3.1980.560-572)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.1980.560-572

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Chen, Chueh-An, Chiao-Lin Lee, Po-Kang Yang, Dung-Sheng Tsai, and Chuan-Pei Lee. "Active Site Engineering on Two-Dimensional-Layered Transition Metal Dichalcogenides for Electrochemical Energy Applications: A Mini-Review." Catalysts 11, no. 2 (January 21, 2021): 151. http://dx.doi.org/10.3390/catal11020151.

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Two-dimensional-layered transition metal dichalcogenides (2D-layered TMDs) are a chemically diverse class of compounds having variable band gaps and remarkable electrochemical properties, which make them potential materials for applications in the field of electrochemical energy. To date, 2D-layered TMDs have been wildly used in water-splitting systems, dye-sensitized solar cells, supercapacitors, and some catalysis systems, etc., and the pertinent devices exhibit good performances. However, several reports have also indicated that the active sites for catalytic reaction are mainly located on the edge sites of 2D-layered TMDs, and their basal plane shows poor activity toward catalysis reaction. Accordingly, many studies have reported various approaches, namely active-site engineering, to address this issue, including plasma treatment, edge site formation, heteroatom-doping, nano-sized TMD pieces, highly curved structures, and surface modification via nano-sized catalyst decoration, etc. In this article, we provide a short review for the active-site engineering on 2D-layered TMDs and their applications in electrochemical energy. Finally, the future perspectives for 2D-layered TMD catalysts will also be briefly discussed.

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Sun, Yifan, and Sheng Dai. "High-entropy materials for catalysis: A new frontier." Science Advances 7, no. 20 (May 2021): eabg1600. http://dx.doi.org/10.1126/sciadv.abg1600.

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Entropy plays a pivotal role in catalysis, and extensive research efforts have been directed to understanding the enthalpy-entropy relationship that defines the reaction pathways of molecular species. On the other side, surface of the catalysts, entropic effects have been rarely investigated because of the difficulty in deciphering the increased complexities in multicomponent systems. Recent advances in high-entropy materials (HEMs) have triggered broad interests in exploring entropy-stabilized systems for catalysis, where the enhanced configurational entropy affords a virtually unlimited scope for tailoring the structures and properties of HEMs. In this review, we summarize recent progress in the discovery and design of HEMs for catalysis. The correlation between compositional and structural engineering and optimization of the catalytic behaviors is highlighted for high-entropy alloys, oxides, and beyond. Tuning composition and configuration of HEMs introduces untapped opportunities for accessing better catalysts and resolving issues that are considered challenging in conventional, simple systems.

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Maksimchuk, Nataliya V., Olga V. Zalomaeva, Igor Y. Skobelev, Konstantin A. Kovalenko, Vladimir P. Fedin, and Oxana A. Kholdeeva. "Metal–organic frameworks of the MIL-101 family as heterogeneous single-site catalysts." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, no. 2143 (March 14, 2012): 2017–34. http://dx.doi.org/10.1098/rspa.2012.0072.

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In this short review paper, we survey our recent findings in the catalytic applications of mesoporous metal–organic frameworks of the MIL-101 family (Fe- and Cr-MIL-101) and demonstrate their potential in two types of liquid-phase processes: (i) selective oxidation of hydrocarbons with green oxidants—O 2 and tert -butyl hydroperoxide—and (ii) coupling reaction of organic oxides with CO 2 . A comparison with conventional single-site catalysts is made with special attention to issues of the catalyst's resistance to metal leaching and the nature of catalysis.

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Abdouss, Majid, Maryam Arsalanfar, Nima Mirzaei, and Yahya Zamani. "Effect of Drying Conditions on the Catalytic Performance, Structure, and Reaction Rates over the Fe-Co-Mn/MgO Catalyst for Production of Light Olefins." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 1 (April 2, 2018): 97. http://dx.doi.org/10.9767/bcrec.13.1.1222.97-112.

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The MgO-supported Fe-Co-Mn catalysts, prepared using co-precipitation procedure, were tested for production of light olefins via CO hydrogenation reaction. The effect of a range of drying conditions including drying temperature and drying time on the structure and catalytic performance of Fe-Co-Mn/MgO catalyst for Fischer-Tropsch synthesis was investigated in a fixed bed micro-reactor under the same operational conditions of T = 350 °C, P = 1 bar, H2/CO = 2/1, and GHSV = 4500 h-1. It was found that the catalyst dried at 120 °C for 16 h has shown the best catalytic performance for CO hydrogenation. Furthermore, the effect of drying conditions on different surface reaction rates was also investigated and it was found that the precursors drying conditions influenced the rates of different surface reactions. Characterization of catalyst precursors and calcined samples (fresh and used) was carried out using powder X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Brunauer-Emmett-Teller (BET) measurements, Temperature Programmed Reduction (TPR), Thermal Gravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). Characterization results showed that different investigated variables (drying conditions) influenced the structure, morphology and catalytic performance of the ternary catalysts. Copyright © 2018 BCREC Group. All rights reservedReceived: 21st May 2017; Revised: 29th August 2017; Accepted: 7th September 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018How to Cite: Abdouss, M., Arsalanfar, M., Mirzaei, N., Zamani, Y. (2018). Effect of Drying Conditions on the Catalytic Performance, Structure, and Reaction Rates over the Fe-Co-Mn/MgO Catalyst for Production of Light Olefins. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (1): 97-112 (doi:10.9767/bcrec.13.1.1222.97-112)

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Kluger, Ronald. "Catalyzing decarboxylation by taming carbon dioxide." Pure and Applied Chemistry 87, no. 4 (April 1, 2015): 353–60. http://dx.doi.org/10.1515/pac-2014-0907.

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AbstractDecarboxylation reactions on enzymes are consistently much faster than their nonenzymic counterparts. Examination of the potential for catalysis in the nonenzymic reactions revealed that the reaction is slowed by the failure of CO2 to be launched into solution upon C–C bond cleavage. Catalysts can facilitate the reaction by weakening the C–CO2H bond but this is not sufficient. Converting the precursor of CO2 into a precursor of bicarbonate facilitates the forward reaction as does protonation of the nascent carbanion.

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Zhou, Ying Mei, Xiao Hui Wang, Ke Ying Cai, Ji Ming Wu, Peng Wang, and Ming Song. "Preparation of Nitrogen-Doped Carbon Material from Monosodium Glutamate and Its Catalytic Performance." Bulletin of Chemical Reaction Engineering & Catalysis 14, no. 1 (April 15, 2019): 28. http://dx.doi.org/10.9767/bcrec.14.1.2377.28-34.

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N-doped carbon materials (NCMs) are generally used as electrode materials, and seldom used as catalysts in chemical reaction. In this work, NCMs were prepared by high-temperature pyrolysis using monosodium glutamate as sources of both carbon and nitrogen, magnesium acetate as a porogen, and nickel hydroxide as a graphitization catalyst. The catalytic performance of NCMs was investigated in the reduction of 4-nitrophenol (4-NP) with potassium borohydride at 30 ºC. As metal-free catalysts, all of the NCMs can catalyze the reaction. The graphitization degree and N-doped amount of NCM have a great influence on the catalytic activity. The NCM annealed at 800 ºC has higher activity and stability. The reaction rate constant can reach 0.57 min-1, and the activation energy was about 36.4 kJ/mol. Copyright © 2019 BCREC Group. All rights reservedReceived: 19th March 2018; Revised: 16th August 2018; Accepted: 20th August 2018; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Zhou, Y.M., Wang, X.H., Cai, K.Y., Wu, J.M., Wang, P., Song, M. (2019). Preparation of Nitrogen-Doped Graphene from Monosodium Glutamate and Its Catalytic Performance. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 28-34 (doi:10.9767/bcrec.14.1.2237.28-34)Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.2237.28-34

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Chen, Yan-Liang, Yun-Hao Chou, Chia-Lin Hsieh, Shean-Jaw Chiou, Tzu-Pin Wang, and Chi-Ching Hwang. "Rational Engineering of 3α-Hydroxysteroid Dehydrogenase/Carbonyl Reductase for a Biomimetic Nicotinamide Mononucleotide Cofactor." Catalysts 12, no. 10 (September 21, 2022): 1094. http://dx.doi.org/10.3390/catal12101094.

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Enzymes are powerful biological catalysts for natural substrates but they have low catalytic efficiency for non-natural substrates. Protein engineering can be used to optimize enzymes for catalysis and stability. 3α-Hydroxysteroid dehydrogenase/carbonyl reductase (3α-HSD/CR) catalyzes the oxidoreduction reaction of NAD+ with androsterone. Based on the structure and catalytic mechanism, we mutated the residues of T11, I13, D41, A70, and I112 and they interacted with different portions of NAD+ to switch cofactor specificity to biomimetic cofactor nicotinamide mononucleotide (NMN+). Compared to wild-type 3α-HSD/CR, the catalytic efficiency of these mutants for NAD+ decreased significantly except for the T11 mutants but changed slightly for NMN+ except for the A70K mutant. The A70K mutant increased the catalytic efficiency for NMN+ by 8.7-fold, concomitant with a significant decrease in NAD+ by 1.4 × 104-fold, resulting in 9.6 × 104-fold cofactor specificity switch toward NMN+ over NAD+. Meanwhile, the I112K variant increased the thermal stability and changed to a three-state transition from a two-state transition of thermal unfolding of wild-type 3α-HSD/CR by differential scanning fluorimetry. Molecular docking analysis indicated that mutations on these residues affect the position and conformation of the docked NAD+ and NMN+, thereby affecting their activity. A70K variant sterically blocks the binding with NAD+, restores the H-bonding interactions of catalytic residues of Y155 and K159 with NMN+, and enhances the catalytic efficiency for NMN+.

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Zhang, Lian Zi, and Hao Yuan Sun. "Development of Catalysts for Synthesizing Methanol from Syngas." Materials Science Forum 1053 (February 17, 2022): 165–69. http://dx.doi.org/10.4028/p-0eor9r.

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At present, methanol is one of the most basic organic chemical raw materials and energy storage media. With the development of chemical technology and energy storage technology, its application becomes more and more extensive, and the methanol market prospects are unlimited. Industrial-scale methanol is generally prepared by using synthesis gas containing hydrogen, carbon monoxide, and carbon dioxide as raw materials and reacting under a certain pressure, temperature, and catalyst. Therefore, the development of the methanol industry largely depends on the development of catalysts and the improvement of their performance. Metal catalysts are mainly used in the industry for reaction. This article reviews several metal catalysts used to synthesize methanol from syngas. Copper-based and iron-based catalysts are widely used, and the emerging rhodium and its ligand catalysts exhibit good catalytic performance in low-temperature catalysis. In the future, the scientific research team will focus on in-depth research on preparation methods, active centers, catalytic reaction kinetics, durability, metal ligands, raw material prices, etc., to lay a solid foundation for the industrial application of syngas to methanol in advance.

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Liu, Ge, Xuezhi Ouyang, Xue-Ling Wei, Wei-Wei Bao, Xiao-Hua Feng, and Jun-Jun Zhang. "Coupling Interface Construction of Ni(OH)2/MoS2 Composite Electrode for Efficient Alkaline Oxygen Evolution Reaction." Catalysts 12, no. 9 (August 29, 2022): 966. http://dx.doi.org/10.3390/catal12090966.

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The transition metal-based catalysts have excellent electrochemical oxygen evolution reaction catalytic activity in alkaline electrolytes, attracting a significant number of researchers’ attention. Herein, we used two-step hydrothermal and solvothermal methods to prepare a Ni(OH)2/MoS2/NF electrocatalyst. The electrocatalyst displayed outstanding OER activity in 1.0 M KOH electrolyte with lower overpotential (296 mV at 50 mA·cm−2) and remarkable durability. Comprehensive analysis shows that reinforcement of the catalytic function is due to the synergistic effect between Ni(OH)2 and MoS2, which can provide more highly active sites for the catalyst. This also provides a reliable strategy for the application of heterogeneous interface engineering in energy catalysis.

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Zhai, Peng, Geng Sun, Qingjun Zhu, and Ding Ma. "Fischer-Tropsch synthesis nanostructured catalysts: understanding structural characteristics and catalytic reaction." Nanotechnology Reviews 2, no. 5 (October 1, 2013): 547–76. http://dx.doi.org/10.1515/ntrev-2013-0025.

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AbstractOne key goal of heterogeneous catalysis study is to understand the correlation between the catalyst structure and its corresponding catalytic activity. In this review, we focus on recent strategies to synthesize well-defined Fischer-Tropsch synthesis (FTS) nanostructured catalysts and their catalytic performance in FTS. The development of those promising catalysts highlights the potentials of nanostructured materials to unravel the complex and dynamic reaction mechanism, particularly under the in situ reaction conditions. The crucial factors associated with the catalyst compositions and structures and their effects on the FTS activities are discussed with an emphasis on the role of theoretical modeling and experimental results.

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Hartman, Ryan L., and Lars C. Grabow. "Editorial overview: Data-centric catalysis and reaction engineering." Current Opinion in Chemical Engineering 38 (December 2022): 100875. http://dx.doi.org/10.1016/j.coche.2022.100875.

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Hinde, Peter, Vladimir Demidyuk, Alkis Gkelios, and Carl Tipton. "Plasma Catalysis: A Review of the Interdisciplinary Challenges Faced : Realising the potential of plasma catalysis on a commercial scale." Johnson Matthey Technology Review 64, no. 2 (April 1, 2020): 138–47. http://dx.doi.org/10.1595/205651320x15759961130711.

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The work presented here introduces the topic of plasma catalysis through selected work in scientific literature and commercial applications, as well as identifying some of the key challenges faced when attempting to utilise non-thermal atmospheric plasma catalysis across multidisciplinary boundaries including those of physics, chemistry and electrical engineering. Plasma can be generated by different methods at many energy levels and can initiate chemical reactions; the main challenges are to selectively initiate desirable reactions either within a process stream or at the surface of a material. The material, which may have intrinsic catalytic properties, the nature of the process gas and the geometry of the reactor will influence the products formed. Previous work has shown that the mechanism for plasma-initiated reactions can be different to that occurring from more traditional thermally stimulated reactions, which opens up possibilities of using different catalytic materials to optimise the reaction rate and product speciation. In addition, the influence of a plasma at the surface of a material and the effects that can be introduced will be discussed.

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Sabit, F., M. Shakipov, P. Skrzypacz, and B. Golman. "Dead-Core Solutions to Simple Catalytic Reaction Problems in Chemical Engineering." Eurasian Chemico-Technological Journal, no. 1 (February 20, 2019): 29. http://dx.doi.org/10.18321/ectj784.

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The catalytic chemical reaction is usually carried out in a pellet where the catalyst is distributed throughout its porous structure. The selectivity, yield and productivity of the catalytic reactor often depend on the rates of chemical reactions and the rates of diffusion of species involved in the reactions in the pellet porous space. In such systems, the fast reaction can lead to the consumption of reactants close to the external pellet surface and creation of the dead core where no reaction occurs. This will result in an inefficient use of expensive catalyst. In the discussed simplified diffusion-reaction problems a nonlinear reaction term is of power-law type with a small positive reaction exponent. Such reaction term represents the kinetics of catalytic reaction accompanied by a strong adsorption of the reactant. The ways to calculate the exact solutions possessing dead cores are presented. It was also proved analytically that the exact solution of the nonlinear two-point boundary value problem satisfies physical a-priori bounds. Furthermore, the approximate solutions were obtained using the orthogonal collocation method for pellets of planar, spherical and cylindrical geometries. Numerical results confirmed that the length of the dead core increases for the more active catalysts due to the larger values of the reaction rate constant. The dead core length also depends on the pellet geometry.

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Peyrovi, Mohammad Hasan, Nastaran Parsafard, and Hosein Hasanpour. "Catalytic Study of the Partial Oxidation Reaction of Methanol to Formaldehyde in the Vapor Phase." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 3 (December 4, 2018): 520. http://dx.doi.org/10.9767/bcrec.13.3.2048.520-528.

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In the present work, several parameters affecting on the catalytic behavior were studied in the process of partial oxidation of methanol to formaldehyde, such as: Mo/Fe ratio in unsupported catalysts, weight percent of the metallic phase in the supported catalysts, the effect of different supports, the method of Mo-Fe deposition on the supports, and the stability of the prepared catalysts against coke. These catalysts were characterized by X-ray diffraction (XRD), Fourier Transform Infra Red (FT-IR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), N2 adsorption-desorption, and Atomic Adsorption Spectroscopy (AAS) methods. The best results (the methanol conversion = 97 % and formaldehyde selectivity = 96 %) were obtained for Mo-Fe/g-Al2O3 prepared by co-precipitation method with Mo/Fe = 1.7, 50 wt.% of Fe-Mo phase, 2 mL/h methanol flow rate, and 120 mL/min air flow rate at 350 oC. Copyright © 2018 BCREC Group. All rights reservedReceived: 1st January 2018; Revised: 17th July 2018; Accepted: 24th July 2018How to Cite: Peyrovi, M.H., Parsafard, N., Hasanpour, H. (2018). Catalytic Study of the Partial Oxidation Reaction of Methanol to Formaldehyde in the Vapor Phase. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 520-528 (doi:10.9767/bcrec.13.3.2048.520-528)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2048.520-528

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Abdallah, Heba. "A Review on Catalytic Membranes Production and Applications." Bulletin of Chemical Reaction Engineering & Catalysis 12, no. 2 (August 1, 2017): 136. http://dx.doi.org/10.9767/bcrec.12.2.462.136-156.

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The development of the chemical industry regarding reducing the production cost and obtaining a high-quality product with low environmental impact became the essential requirements of the world in these days. The catalytic membrane is considered as one of the new alternative solutions of catalysts problems in the industries, where the reaction and separation can be amalgamated in one unit. The catalytic membrane has numerous advantages such as breaking the thermodynamic equilibrium limitation, increasing conversion rate, reducing the recycle and separation costs. But the limitation or most disadvantages of catalytic membranes related to the high capital costs for fabrication or the fact that manufacturing process is still under development. This review article summarizes the most recent advances and research activities related to preparation, characterization, and applications of catalytic membranes. In this article, various types of catalytic membranes are displayed with different applications and explained the positive impacts of using catalytic membranes in various reactions. Copyright © 2017 BCREC Group. All rights reserved.Received: 1st April 2016; Revised: 14th February 2017; Accepted: 22nd February 2017How to Cite: Abdallah, H. (2017). A Review on Catalytic Membranes Production and Applications. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (2): 136-156 (doi:10.9767/bcrec.12.2.462.136-156)Permalink/DOI: http://dx.doi.org/10.9767/bcrec.12.2.462.136-156

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Tagawa, Tomohiko. "Reaction Engineering of Microchannel Catalytic Reactors for Green Process." Applied Mechanics and Materials 625 (September 2014): 285–88. http://dx.doi.org/10.4028/www.scientific.net/amm.625.285.

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It is essential to introduce green sustainable chemical process into developing countries. Use of microchannel reactors is one of the future solutions. Especially, application of multiphase catalytic system should be studied in the reaction engineering view point. Examples of application of catalysts to microchannel reactors were introduced such as: Use of phase transfer catalysts in multi phase parallel flow reactors, Use of phase transfer catalysts with the aid of ultrasonic irradiation in multiphase slug flow capillary reactors and Preparation of gas phase tube wall type catalytic reactors which were evaluated with microscopic FT-IR and UV spectrometer.

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Mouanni, Sihem, Tassadit Mazari, Sihem Benadji, Leila Dermeche, Catherine Marchal-Roch, and Cherifa Rabia. "Simple and Green Adipic Acid Synthesis from Cyclohexanone and/or Cyclohexanol Oxidation with Efficient (NH4)xHyMzPMo12O40 (M: Fe, Co, Ni) Catalysts." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 2 (June 11, 2018): 386. http://dx.doi.org/10.9767/bcrec.13.2.1749.386-392.

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The oxidation of cyclohexanone and/or cyclohexanol to adipic acid (AA) was performed at 90 °C with a reaction time of 20 h, in the presence of H2O2 as oxidant and transition metal substituted ammonia polyoxometalates of formula, (NH4)xHyMzPMo12O40 (M: Fe, Co, or Ni, and x = 2.5 or 2.28) as catalysts. The catalytic results showed that the AA yield is sensitive to the transition metal nature and to the reaction conditions (sample weight and substrate amount). The (NH4)2.29H0.39Co0.16PMo12O40 was found to be the better catalytic system toward AA synthesis from cyclohexanone oxidation, with 40% of AA yield Copyright © 2018 BCREC Group. All rights reservedReceived: 12nd November 2017; Revised: 18th February 2018; Accepted: 19th February 2018; Available online: 11st June 2018; Published regularly: 1st August 2018How to Cite: Mouanni, S., Mazari, T., Benadji, S., Dermeche, L., Marchal-Roch, C., Rabia, C. (2018). Simple and Green Adipic Acid Synthesis from Cyclohexanone and/or Cyclohexanol Oxidation with Efficient (NH4)xHyMzPMo12O40 (M: Fe, Co, Ni) Catalysts. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (2): 386-392 (doi:10.9767/bcrec.13.2.1749.386-392)

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Nifant’ev, Ilya, Pavel Ivchenko, Alexander Tavtorkin, Alexey Vinogradov, and Alexander Vinogradov. "Non-traditional Ziegler-Natta catalysis in α-olefin transformations: reaction mechanisms and product design." Pure and Applied Chemistry 89, no. 8 (July 26, 2017): 1017–32. http://dx.doi.org/10.1515/pac-2016-1131.

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AbstractThis paper describes our recent results in the field of zirconocene-catalyzed α-oltfin transformations, and focuses on questions regarding the reaction mechanism, rational design of zirconocene pre-catalysts, as well as prospective uses of α-olefin products. It has been determined that a wide range of α-olefin-based products, namely vinylidene dimers, oligomers and polymers, can be prepared via catalysis by zirconocene dichlorides, activated by a minimal (10–20 eq.) amount of MAO. We assumed that in the presence of minimal quantities of MAO, various types of zirconocene catalysts form different types of catalytic particles. In the case of bis-cyclopentadienyl complexes, the reactive center is formed under the influence of R2AlCl, which makes the chain termination via β-hydride elimination significantly easier, with α-olefin dimers being formed as the primary product. Bis-indenyl complexes and their heteroanalogues, form stable cationic catalytic particles and effectively catalyze the polymerization. Mono-indenyl and mono-substituted bis-cyclopentadienyl-ansa complexes catalyze α-olefin oligomerization. Effective catalysts of dimerization, oligomerization and polymerization of α-olefins in the presence of minimal MAO quantities are proposed. Prospects of using α-olefin dimers, oligomers and polymers in the synthesis of branched hydrocarbon functional derivatives (dimers), high quality, low viscosity motor oils (oligomers), and thickeners and absorbents (polymers) are examined.

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Eghbali, Paria, Bilal Nişancı, and Önder Metin. "Graphene hydrogel supported palladium nanoparticles as an efficient and reusable heterogeneous catalysts in the transfer hydrogenation of nitroarenes using ammonia borane as a hydrogen source." Pure and Applied Chemistry 90, no. 2 (February 23, 2018): 327–35. http://dx.doi.org/10.1515/pac-2017-0714.

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Abstract Addressed herein is a facile one-pot synthesis of graphene hydrogel (GHJ) supported Pd nanoparticles (NPs), namely Pd-GHJ nanocomposites, via a novel method that comprises the combination of hydrothermal treatment and polyol reduction protocols in water. The structure Pd-GHJ nanocomposites were characterized by TEM, HR-TEM, XRD, XPS, Raman spectroscopy and BET surface area analysis. Then, Pd-GHJ nanocomposites were used as a heterogeneous catalysts in the tandem dehydrogenation of ammonia borane and hydrogenation of nitroarenes (Ar–NO2) to anilines (Ar–NH2) in the water/methanol mixture at room temperature. A variety of Ar–NO2 derivatives (total 9 examples) were successfully converted to the corresponding Ar–NH2 by the help of Pd-GHJ nanocomposites catalyzed tandem reactions with the conversion yields reaching up to 99% in only 20 min reaction time. Moreover, Pd-GHJ nanocomposites were demonstrated to be the reusable catalysts in the tandem reactions by preserving their initial catalytic performance after five consecutive catalytic cycles. It is believed that the presented synthesis protocol for the Pd-GHJ nanocomposites and the catalytic tandem hydrogenation reactions will make a significant contribution to the catalysis and synthetic organic chemistry fields.

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Kulczycki, Andrzej, Czesław Kajdas, and Hong Liang. "On the mechanism of catalysis induced by mechano-activation of solid body." Materials Science-Poland 32, no. 4 (December 1, 2014): 583–91. http://dx.doi.org/10.2478/s13536-014-0228-7.

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AbstractThe paper presents a new model of the mechanism of mechanocatalysis and tribocatalysis. The reason for the increase in heterogeneous catalysis effect after mechanical activation of a catalyst has not been fully understood yet. There is no known theory, which would explain the mechanism of the influence of mechanical energy introduced to catalyst particles on the rate of chemical reaction. All existing theories are based on Arrhenius equation and assume that catalysts increase reaction rate due to decreasing of activation energy E a. We hypothesize that both for standard and catalyzed heterogeneous reactions the same E a (real activation energy) is needed to trigger the reaction processes and the catalytic effect is the result of energy introduced to the reaction system, its accumulation by a catalyst and then emission of high flux of energy to the space near the catalyst particles. This energy emitted by molecules of reagents can reach a value equal to the value of E a at lower ambient temperature than it would result from Arrhenius equation. This hypothesis is based on α i model described in previous papers by Kajdas and Kulczycki as well as the results of tribochemical research described by Hong Liang et al., which demonstrate that the reaction rate is higher than that resulting from temperature.

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Yates, D. J. C., S. K. Behal, and B. H. Kear. "Studies of reactions between gaseous organo-silicon compounds and metal surfaces." Journal of Materials Research 3, no. 4 (August 1988): 714–22. http://dx.doi.org/10.1557/jmr.1988.0714.

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A procedure for modifying the surface composition of catalytically active metals with silicon-containing gaseous reactants has been developed. This new gas-solid reaction method is unique in that it can be used for the in situ synthesis of catalytically interesting materials, which cannot be done by conventional solid-solid reaction techniques. Using an oxygen-free silicon compound (e.g., hexamethyldisilazane, HMDS), the metals studied fall into two categories: those that involve reaction followed by diffusion, and those that exhibit surface reaction only. The first group, consisting of the metals Ni, V, Rh, Pt and Pd, formed thick (up to 0.6μ) Si diffusion layers, after reaction at 430 °C for a few hours, with either H2/HMDS or Ar/HMDS mixtures. Under the same conditions, the second group of metals, Fe and Co, showed thin (∼ 500 Å) overlayers containing silicon, but with no diffusion. The only nonmetal (graphite) studied so far showed no reaction, within the detectability limits of Auger spectroscopy. This observation shows that these reactions are catalytically induced by certain metal surfaces; in other words, they selectively take place on metals. These findings clearly have important implications for catalysis. For example, the metal surfaces of oxide-supported metal catalysts can, in principle, be selectively modified by gas-phase reactants. This treatment can readily be accomplished in situ in the catalytic reactor. The above reactions may well result in a new class of metallic catalysts, with one of the components being silicon. Furthermore, gas-phase compounds containing the elements aluminum, boron, and germanium are known to react with metals in an analogous manner, which further extends the range of possibilities for the synthesis of new catalytic materials.

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He, Dongmei, and István T. Horváth. "Molecular Engineering in Catalysis: Immobilization of Shvo's Ruthenium Catalyst to Silica Coated Magnetic Nanoparticles." Periodica Polytechnica Chemical Engineering 65, no. 1 (October 21, 2020): 1–11. http://dx.doi.org/10.3311/ppch.16052.

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The functionalized Shvo’s catalyst precursor {3,4-[p-(EtO)3Si(CH2)3OPh]2-2,5-Ph2(η4-C4CO)}Ru(CO)3 (1) was covalently immobilized to the surface of magnetic nanoparticles, MNPs, including magnetite (Fe3O4) and magnetite covered by one, two and three independently added silica (SiO2) coatings (Fe3O4@SiO2, Fe3O4@SiO2@SiO2, Fe3O4@SiO2@SiO2@SiO2) resulting in the corresponding ruthenium catalysts Fe3O4@Ru (2a), Fe3O4@SiO2@Ru (2b), Fe3O4@SiO2@SiO2@Ru (2c), and Fe3O4@SiO2@SiO2@SiO2@Ru (2d). These catalysts were characterized by FT-IR, TEM, EDX, powder XRD, BET surface area analysis and BJH pore size and volume analysis. The catalytic performances of 2a–2d were tested for the conversion of levulinic acid (LA) to gamma-valerolactone (GVL) using formic acid (FA) as the hydrogen source. The catalysts were separated from the reaction mixture by using an external magnet. Catalysts on the silica coated MNPs showed higher activity than that of immobilized directly to Fe3O4. There were no significant differences in TONs, TOFs and yields of GVL using catalysts 2b–2d. Leaching test of the four catalysts showed that by increasing the number of independent silica coatings on the surface of magnetite significantly decreased iron leaching. The recyclability of 2b was investigated and it was reused several times without significant loss of the catalytic activity. Hot filtration test of 2c and 2d has established that the catalytic activity was due to the supported ruthenium catalyst and not from some active ruthenium species leached from the solid support to the solution under the reaction conditions.

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Ćwikła-Bundyra, Wiesława, and Dobiesław Nazimek. "Influence of Palladium Crystallite Size on the Course of the DENOX Reaction." Adsorption Science & Technology 19, no. 5 (June 2001): 381–84. http://dx.doi.org/10.1260/0263617011494240.

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Catalysis is one of the important fields in the industry where small metal particles are applied. The effect of the metal crystallite size in the catalytic reduction process has investigated for palladium, the present paper reporting on the effect of the Pd dispersion on the course of the reaction between NO and CO. Such studies also allowed changes in the activity and selectivity of the process and the concentration of B5 sites on the surface of Pd catalysts to be traced.

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Coppens, Marc-Olivier, and Theodore T. Tsotsis. "Editorial overview: Reaction and catalysis engineering: Back to fundamentals." Current Opinion in Chemical Engineering 13 (August 2016): ix—xi. http://dx.doi.org/10.1016/j.coche.2016.08.012.

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Chaudhari, Raghunath V., and Patrick L. Mills. "Multiphase catalysis and reaction engineering for emerging pharmaceutical processes." Chemical Engineering Science 59, no. 22-23 (November 2004): 5337–44. http://dx.doi.org/10.1016/j.ces.2004.07.105.

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BAIKER, A. "ChemInform Abstract: Heterogeneous Catalysis. From Fundamentals to Reaction Engineering." ChemInform 27, no. 36 (August 5, 2010): no. http://dx.doi.org/10.1002/chin.199636275.

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Gamal, Ahmed, Kamel Eid, Muftah H. El-Naas, Dharmesh Kumar, and Anand Kumar. "Catalytic Methane Decomposition to Carbon Nanostructures and COx-Free Hydrogen: A Mini-Review." Nanomaterials 11, no. 5 (May 6, 2021): 1226. http://dx.doi.org/10.3390/nano11051226.

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Catalytic methane decomposition (CMD) is a highly promising approach for the rational production of relatively COx-free hydrogen and carbon nanostructures, which are both important in multidisciplinary catalytic applications, electronics, fuel cells, etc. Research on CMD has been expanding in recent years with more than 2000 studies in the last five years alone. It is therefore a daunting task to provide a timely update on recent advances in the CMD process, related catalysis, kinetics, and reaction products. This mini-review emphasizes recent studies on the CMD process investigating self-standing/supported metal-based catalysts (e.g., Fe, Ni, Co, and Cu), metal oxide supports (e.g., SiO2, Al2O3, and TiO2), and carbon-based catalysts (e.g., carbon blacks, carbon nanotubes, and activated carbons) alongside their parameters supported with various examples, schematics, and comparison tables. In addition, the review examines the effect of a catalyst’s shape and composition on CMD activity, stability, and products. It also attempts to bridge the gap between research and practical utilization of the CMD process and its future prospects.

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Paranjpe, Rucha, A. K. Suresh, and Preeti Aghalayam. "Understanding Pt–Rh Synergy in a Three-Way Catalytic Converter." International Journal of Chemical Reactor Engineering 11, no. 1 (October 30, 2013): 535–42. http://dx.doi.org/10.1515/ijcre-2013-0072.

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Abstract NO reduction to N2 is the key reaction for efficient operation of a three-way catalytic converter (TWC). It is reported that metal catalysts Pt and Rh co-exist as individual metals in a TWC to give synergistic performance. In this article, we have studied the NO + CO reaction for a 1:1 physical mixture of silica supported Pt and Rh catalysts using fixed bed experiments and microkinetic modeling. The microkinetic model [14] for the reaction on single metals Pt and Rh is simulated for the mixture case in CHEMKIN PRO®. It is observed that the mixture maintains the activity while producing less N2O (by-product of NO + CO reaction) thus enhancing N2 selectivity inspite of having only half amount of Rh. Analysis of surface coverages on individual metals in mixture shows that in the presence of Pt, CO poisoning of Rh is reduced at lower temperature leading to better overall conversion and selectivity. This has potential benefit in automotive catalysis, as it results in the formation of significantly lower amounts of N2O, an undesirable side-product and greenhouse gas; at a lower cost than if pure Pt/Rh catalysts were used.

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Šmíd, Bretislav, Toshiyuki Mori, M. Takahashi, Ding Rong Ou, V. Matolín, and Iva Matolínova. "Fabrication and Microanalysis of Nano-Structured CuO_X-CeO₂ Catalysts for CO Oxidation Reaction." Advanced Materials Research 15-17 (February 2006): 261–66. http://dx.doi.org/10.4028/www.scientific.net/amr.15-17.261.

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Carbon monoxide (CO) is a significant air pollutant produced in incomplete oxidation of carbon in combustion. From the viewpoint of environmental protection, it is important that the concentration of CO gas is lowered in air. Catalysis is proving to be an effective route for removing this pollutant. Therefore, a design of nano-structured catalysts with high efficiency is required. In the present work, we focus on a development of nano-size CuOx-CeO2 catalysts for CO oxidation reaction. To prepare nano-structured Cu loaded CeO2 catalysts, a combined method of the conventional impregnation and ammonium carbonate co-precipitation was examined. Morphology, crystal phase and surface structure of prepared catalysts were characterized using High-Resolution Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM) and Powder X-ray Diffraction (XRD). Catalytic properties of CuOx-CeO2 for CO oxidation were investigated in gas flow reactor system under atmospheric pressure and compared with copper oxide loaded zinc oxide. We expected that nano-structured CuOx-CeO2 catalysts could be used for removing CO produced in a wet reforming reaction of fuel cell applications.

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Zhang, Hong, Minjing Shang, Yuchao Zhao, and Yuanhai Su. "Process Intensification of 2,2′-(4-Nitrophenyl) Dipyrromethane Synthesis with a SO3H-Functionalized Ionic Liquid Catalyst in Pickering-Emulsion-Based Packed-Bed Microreactors." Micromachines 12, no. 7 (July 5, 2021): 796. http://dx.doi.org/10.3390/mi12070796.

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A stable water-in-oil Pickering emulsion was fabricated with SO3H-functionalized ionic liquid and surface-modified silica nanoparticles and used for 2,2′-(4-nitrophenyl) dipyrromethane synthesis in a packed-bed microreactor, exhibiting high reaction activity and product selectivity. The compartmentalized water droplets of the Pickering emulsion had an excellent ability to confine the ionic liquid against loss under continuous-flow conditions, and the excellent durability of the catalytic system without a significant decrease in the reaction efficiency and selectivity was achieved. Compared with the reaction performance of a liquid–liquid slug-flow microreactor and batch reactor, the Pickering-emulsion-based catalytic system showed a higher specific interfacial area between the catalytic and reactant phases, benefiting the synthesis of 2,2′-(4-nitrophenyl) dipyrromethane and resulting in a higher yield (90%). This work indicated that an increase in the contact of reactants with catalytic aqueous solution in a Pickering-emulsion-based packed-bed microreactor can greatly enhance the synthetic process of dipyrromethane, giving an excellent yield of products and a short reaction time. It was revealed that Pickering-emulsion-based packed-bed microreactors with the use of ionic liquids as catalysts for interfacial catalysis have great application potential in the process of intensification of organic synthesis.

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Sun, Qian, Chun Zeng, Meng-Meng Xing, Bo Chen, Dan Zhao, San-Guo Hong, and Ning Zhang. "Efficiently Engineering Cu-Based Oxide by Surface Embedding of Ce for Selective Catalytic Reduction of NO with NH3." Nano 14, no. 06 (June 2019): 1950079. http://dx.doi.org/10.1142/s1793292019500796.

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Deliberately engineering oxide composites on constructing and manipulating interactive structures particularly in surface layers was highly desirable for heterogeneous catalysis. Herein, upon the redox replacement reaction between Ce(IV) precursor (Ce(NO[Formula: see text] and Cu2O nano-substrate, an attempt to directly engineer the surface structure of Cu-based substrate was performed by the Ce(IV)–Cu2O etching-embedding process, then the obtained powders were thermo-treated to get a series of Ce–O–Cu catalysts with different Ce:Cu molar ratios for NH3 selective catalytic reduction (NH3-SCR) of NO. Characterized by ICP-OES, XRD, Raman, XPS, SEM, BET, H2-TPR, NO- and NH3-TPD measurements, it was demonstrated that the Cu–O–Ce catalysts were structured as CuO matrix with an interactive surface composed by co-present Cu(I)–Cu(II) and Ce(III)–Ce(IV) species, even the introduction of Ce was confined in a quite low loading range (0.83–2.3[Formula: see text]wt.%); such a surface exhibited the distinct synergistic effect with positively manipulated physical-chemistry properties such as active site distributions, redox features and surface reactivity compared to pure CuO and traditional Cu–Ce composite catalyst, leading to attractive catalytic performance such as [Formula: see text]% NO conversion with [Formula: see text]% N2 selectivity and the two-fold TOF enhancement versus traditional catalysts, even SO2 was present in reactant mixture on well-manipulated catalyst (Ce loading at 1.6[Formula: see text]wt.%) These results indicated that the etching-embedding strategy illuminated in this work could be referred as a feasible method to directly engineer and construct interactive oxide composite surface for advanced application as well as current efficient Ce–O–Cu catalytic interface for heterogeneous catalysis.

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Sun, Hao, Kang Sun, Jianchun Jiang, and Zhenggui Gu. "Preparation of 2-Methylnaphthalene from 1-Methylnaphthalene via Catalytic Isomerization and Crystallization." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 3 (December 4, 2018): 512. http://dx.doi.org/10.9767/bcrec.13.3.2650.512-519.

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Large amounts of residual 1-methylnaphthalene are generated when 2-methylnaphthalene is extracted from alkyl naphthalene. In order to transform waste into assets, this study proposes a feasible process for preparing 2-methylnaphthalene from 1-methylnaphthalene through isomerization and crystallization. The 1-methylnaphthalene isomerization was carried out in a fixed-bed reactor over mixed acids-treated HBEA zeolite. The results showed that acidic properties of catalysts and reaction temperature were associated with the 2-methylnaphthalene selectivity, yield and catalytic stability. At a high reaction temperature of 623 K, the 2-methylnaphthalene yield was 65.84 %, and the deactivation rate was much lower. The separation of reaction products was then investigated by two consecutive crystallization processes. Under optimal conditions, the 2-methylnaphthalene purity attained 96.67 % in the product, while the yield was 87.48 % in the refining process. Copyright © 2018 BCREC Group. All rights reservedReceived: 10th May 2018; Revised: 16th July 2018; Accepted: 17th July 2018How to Cite: Sun, H., Sun, K., Jiang, J., Gu, Z. (2018). Preparation of 2-Methylnaphthalene from 1-Methylnaphthalene via Catalytic Isomerization and Crystallization. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 512-519 (doi:10.9767/bcrec.13.3.2650.512-519)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2650.512-519

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Bordet, Alexis, Sami El Sayed, Matthew Sanger, Kyle J. Boniface, Deepti Kalsi, Kylie L. Luska, Philip G. Jessop, and Walter Leitner. "Selectivity control in hydrogenation through adaptive catalysis using ruthenium nanoparticles on a CO2-responsive support." Nature Chemistry 13, no. 9 (July 5, 2021): 916–22. http://dx.doi.org/10.1038/s41557-021-00735-w.

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AbstractWith the advent of renewable carbon resources, multifunctional catalysts are becoming essential to hydrogenate selectively biomass-derived substrates and intermediates. However, the development of adaptive catalytic systems, that is, with reversibly adjustable reactivity, able to cope with the intermittence of renewable resources remains a challenge. Here, we report the preparation of a catalytic system designed to respond adaptively to feed gas composition in hydrogenation reactions. Ruthenium nanoparticles immobilized on amine-functionalized polymer-grafted silica act as active and stable catalysts for the hydrogenation of biomass-derived furfural acetone and related substrates. Hydrogenation of the carbonyl group is selectively switched on or off if pure H2 or a H2/CO2 mixture is used, respectively. The formation of alkylammonium formate species by the catalytic reaction of CO2 and H2 at the amine-functionalized support has been identified as the most likely molecular trigger for the selectivity switch. As this reaction is fully reversible, the catalyst performance responds almost in real time to the feed gas composition.

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Sahoo, Pathik, and Subrata Ghosh. "Space and Time Crystal Engineering in Developing Futuristic Chemical Technology." ChemEngineering 5, no. 4 (October 7, 2021): 67. http://dx.doi.org/10.3390/chemengineering5040067.

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In the coming years, multipurpose catalysts for delivering different products under the same chemical condition will be required for developing smart devices for industrial or household use. In order to design such multipurpose devices with two or more specific roles, we need to incorporate a few independent but externally controllable catalytically active centers. Through space crystal engineering, such an externally controllable multipurpose MOF-based photocatalyst could be designed. In a chemical system, a few mutually independent secondary reaction cycles nested within the principal reaction cycle can be activated externally to yield different competitive products. Each reaction cycle can be converted into a time crystal, where the time consuming each reaction step could be converted as an event and all the reaction steps or events could be connected by a circle to build a time crystal. For fractal reaction cycles, a time polycrystal can be generated. By activating a certain fractal event based nested time crystal branch, we can select one of the desired competitive products according to our needs. This viewpoint intends to bring together the ideas of (spatial) crystal engineering and time crystal engineering in order to make use of the time–space arrangement in reaction–catalysis systems and introduce new aspects to futuristic chemical engineering technology.

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Hradil, J., F. Švec, Č. Koňák, and K. Jurek. "Phase-transfer catalysis. IV. Localization of reaction sites in supported catalysts." Reactive Polymers, Ion Exchangers, Sorbents 9, no. 1 (September 1988): 81–89. http://dx.doi.org/10.1016/0167-6989(88)90053-0.

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Kang, Suk-Hwan, Jae-Hong Ryu, Jin-Ho Kim, Hyo-Sik Kim, Hee Chul Yang, and Dong Yong Chung. "Catalytic Performance for Hydrocarbon Production from Syngas on the Promoted Co-Based Hybrid Catalysts; Influence of Pt Contents." Bulletin of Chemical Reaction Engineering & Catalysis 12, no. 3 (October 28, 2017): 452. http://dx.doi.org/10.9767/bcrec.12.3.592.452-459.

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Fischer-Tropsch synthesis (FTS) reaction from syngas was investigated on the Pt-promoted cobalt-based hybrid catalysts prepared by co-precipitation method in a slurry of ZSM-5 (Si/Al=25). The hybrid catalysts were compared with each other for the different content of Pt as a promoter and are characterized using BET, XRD, H2-TPR and NH3-TPD. Their physicochemical properties were correlated with the activity and selectivity of the catalysts. As results, all hybrid catalysts show the C5-C9 yield (%) higher than that of Co-Al2O3/ZSM-5 catalyst. The Pt-promoted hybrid catalysts were found to be more promising towards production of the hydrocarbons of gasoline range and over C10. Copyright © 2017 BCREC Group. All rights reservedReceived: 12nd July 2016; Revised: 31st May 2017; Accepted: 1st June 2017; Available online: 27th October 2017; Published regularly: December 2017How to Cite: Kang, S.H., Ryu, J.H., Kim, J.H., Kim, H.S., Yang, H.C., Chung, D.Y. (2017). Catalytic Performance for Hydrocarbon Production from Syngas on the Promoted Co-Based Hybrid Catalysts; Influence of Pt Contents. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (3): 452-459 (doi:10.9767/bcrec.12.3.592.452-459)

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Journal articles on the topic 'Catalysis and Reaction Engineering'

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