Artículos de revistas: "Catalyst carrier"

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Teng, Yingyue, Dingze Liu, Qiang Li, Xue Bai y Yinmin Song. "Research Progress on Application in Energy Conversion of Silicon Carbide-Based Catalyst Carriers". Catalysts 13, n.º 2 (19 de enero de 2023): 236. http://dx.doi.org/10.3390/catal13020236.

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In modern industrial production, heterogeneous catalysts play an important role. A catalyst carrier, as a constituent of heterogeneous catalysts, is employed for supporting and loading active components. The catalyst carrier has a considerable impact on the overall acting performance of the catalysts in actual production. Therefore, a catalyst carrier should have some necessary properties such as a high specific surface area, excellent mechanical strength and wear resistance, and better thermal stability. Among the candidate materials, silicon carbide (SiC) has excellent physical and chemical properties due to its special crystal structure; these properties include outstanding thermal conductivity and remarkable mechanical strength and chemical stability. Therefore, SiC materials with a high specific surface area basically meet the requirements of catalyst carriers. Accordingly, SiC has broad application prospects in the field of catalysis and is an ideal material for preparing catalyst carriers. In the present study, we reviewed the preparation methods and the variation in the raw materials used for preparing SiC-based catalyst carriers with high specific surface areas, in particular the research progress on the application of SiC-based catalyst carriers in the field of energy-conversion in recent years. The in-depth analysis indicated that the construction of SiC with a special structure, large-scale synthesis of SiC by utilizing waste materials, low-temperature synthesis of SiC, and exploring the interaction between SiC supports and active phases are the key strategies for future industrial development; these will have far-reaching significance in enhancing catalytic efficiency, reutilization of resources, ecological environmental protection, energy savings, and reductions in energy consumption.

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2

Alexandrova, Julia V., Nataliya V. Maltseva, Tatiana A. Vishnevskaya y Shamil O. Omarov. "INFLUENCE TECHNOLOGY OF PREPARATION ON PROPERTIES Al-Ce-Zr-CARRIERS". Bulletin of the Saint Petersburg State Institute of Technology (Technical University) 55 (2020): 3–9. http://dx.doi.org/10.36807/1998-9849-2020-55-81-3-9.

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The possibility of using Al-Ce-Zr-oxide carrier as a catalyst in the composition of NiO-catalyst in СО oxidation reaction by atmosphere oxygen – as a model oxidation reaction – was shown. The properties of carriers obtained by impregnation and mixing were compared, and the characteristics of the catalytic activity of Al-Ce-Zr-oxide carriers and NiO-catalysts based on them were determined in comparison with the NiO-catalyst deposited on an aluminum oxide carrier.

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3

Zhao, Yue Qing, Qian Yi Jia, Ying Hua Liang, Hong Xia Guo, Feng Feng Li y Xin Hua Liu. "CuO-CoO-MnO/SiO₂ Nanocomposite Aerogel as Catalysts Carrier and Its Cocatalysis Mechanism in the Synthesis of Diphenyl Carbonate". Advanced Materials Research 284-286 (julio de 2011): 707–10. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.707.

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CuO-CoO-MnO/SiO2 nanocomposite aerogel as catalysts carrier was prepared via sol-gel process and CO2supercritical drying (SCD) technique. Catalyst supported by the nanocomposite aerogel was prepared via impregnation method. The catalyst was used for the synthesis of diphenyl carbonate (DPC), and the yield of DPC in mass is up to 26.31%. The catalysis system of PdCl2/Co(OAc)2-Cu(OAc)2-Mn(OAc)2/TBAB/H2BQ is favorable to the synthesis of DPC. PdCl2, acetates of transition metals and H2BQ were the key catalyst, inorganic cocatalyst and organic cocatalyst, respectively. TBAB was the surface active agent of Pd0and stabilizer of Pd2+in the catalysis system.

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4

Bao, Jianguo, Wenxiu Rao, Yi Zhou, Bin Wen, Bo Wang, Guocheng Lv y Libing Liao. "Effect of the Microstructure of Support Materials on Cracking Catalyst Performance". Crystals 13, n.º 1 (10 de enero de 2023): 123. http://dx.doi.org/10.3390/cryst13010123.

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Fluid catalytic cracking (FCC) is a production process that converts petroleum into petroleum products in the presence of catalysts. The performance of an FCC catalyst plays a decisive role in petroleum refining. An FCC catalyst mainly comprises a molecular sieve (catalytic cracking active center), a carrier, and a binder. The carrier can enable the precracking of the heavy oil in its large pore, which can improve the overall activity of the catalyst and the conversion rate of heavy oil. The surface area and pore structure of carrier materials with different microscopic morphologies differ, which significantly affects the precracking of heavy oil molecules. Therefore, here, FCC catalysts were prepared using flake kaolinite, tubular halloysite, natural flake-tube-combined kaolinite, and mixed kaolinite as support materials, respectively. The FCC catalysts were used in FCC-heavy oil, and the influence of the carrier material morphology on the comprehensive performance of the catalysts was studied. The strength and cracking performance of the catalyst prepared using flake Maoming (M) were poor, whereas the catalyst prepared using tubular halloysite exhibited a good strength, high activity, and a good cracking ability for heavy oil. The catalyst prepared using natural flake-tube combined with Suzhou (S) exhibited a good strength and cracking performance, and it has been widely used in the industrial production of FCC catalysts. When 40% tube-like halloysite was mixed into M, the attrition of the prepared catalyst decreased by 0.5 units, the microreactivity increased by 1.4 units, the gasoline + liquefied petroleum gas (LPG) yield increased by 3.09 percentage points, and the gasoline research octane number (RON) increased by 0.6 units. The comprehensive performance of the catalyst can reach or exceed that of the natural-lamp-tube-based kaolin carrier. The results can not only provide guidance for the stable quality control of kaolin, but they can also significantly alleviate the resource restrictions for FCC catalyst production enterprises.

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5

Yang, Rui Qin, Xi Kun Gai, Chuang Xing, Jian Wei Mao y Cheng Xue Lv. "Performance of Cu-Based Catalysts in Low-Temperature Methanol Synthesis". Advanced Materials Research 1004-1005 (agosto de 2014): 1623–26. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.1623.

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The reactions of the methanol synthesis were conducted from the CO/CO2/H2 on the Cu-based catalysts using different solvent at 443 K and 3.0 MPa. The alcohol solvent had the activity in the low-temperature methanol synthesis reaction. The activity of the Cu-based catalyst with ZnO as carrier was higher than that of the catalyst with CeO2, Al2O3, or TiO2 as carrier separately in the reaction. The addition of the CeO2 to the Cu/ZnO catalysts improved the copper species dispersion, so that it was easier for the reduction of the Cu/CeO2-ZnO catalyst than that of the Cu/ZnO catalyst according to the TPR analysis. The variation trend of the BET surface area and the copper surface area was consistent with those of the activity for the Cu/ZnO and the Cu/CeO2-ZnO catalysts in the reaction. The activity of the Cu/CeO2-ZnO catalyst was higher than that of the Cu/ZnO catalyst in the reaction.

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6

Smołka, Szymon y Katarzyna Krukiewicz. "Catalyst Design through Grafting of Diazonium Salts—A Critical Review on Catalyst Stability". International Journal of Molecular Sciences 24, n.º 16 (8 de agosto de 2023): 12575. http://dx.doi.org/10.3390/ijms241612575.

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In the pursuit of designing a reusable catalyst with enhanced catalytic activity, recent studies indicate that electrochemical grafting of diazonium salts is an efficient method of forming heterogeneous catalysts. The aim of this review is to assess the industrial applicability of diazonium-based catalysts with particular emphasis on their mechanical, chemical, and thermal stability. To this end, different approaches to catalyst production via diazonium salt chemistry have been compared, including the immobilization of catalysts by a chemical reaction with a diazonium moiety, the direct use of diazonium salts and nanoparticles as catalysts, the use of diazonium layers to modulate wettability of a carrier, as well as the possibility of transforming the catalyst into the corresponding diazonium salt. After providing descriptions of the most suitable carriers, the most common deactivation routes of catalysts have been discussed. Although diazonium-based catalysts are expected to exhibit good stability owing to the covalent bond created between a catalyst and a post-diazonium layer, this review indicates the paucity of studies that experimentally verify this hypothesis. Therefore, use of diazonium salts appears a promising approach in catalysts formation if more research efforts can focus on assessing their stability and long-term catalytic performance.

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7

Liao, Yalong, Yiyang Wang y Yu Zhang. "Preparation and Catalytic Hydrodechlorination Property of Nano Bimetallic Catalyst Pd–Ni/γAl2O3–SiO2". Catalysts 12, n.º 4 (24 de marzo de 2022): 370. http://dx.doi.org/10.3390/catal12040370.

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Pd–Ni bimetallic catalyst supported on a composite carrier of γAl2O3 and SiO2 was prepared by chemical precipitation methodology enhanced with an ultrasonic wave. In the present paper, the influence of dispersant, carrier, ultrasonic time and intensity on the dechlorination property of the catalysts obtained are investigated. The appearance, morphology and structure of the prepared catalysts were characterized using X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), N2 adsorption–desorption isotherm and X-ray photoelectron spectroscopy spectrometer (XPS). The chemical composition of active gradients in the catalysts was tested with inductively coupled plasma-atomic emission spectrometry (ICP-AES). The metal dispersion and mean particle size of the metallic phase of the prepared catalysts were also determined with CO chemisorption. Results indicate that a nano bimetal Pd–Ni catalyst on an average particle size of 2.45 nm with a distribution range of 1–7 nm supported on a composite carrier of γAl2O3 and SiO2 can be effectively prepared, and that the chlorine content of shellac dechlorinated with the obtained catalyst is 0.18 wt%, which is lower than that reported in the previous literature, indicating the perfect dechlorination property of the catalyst.

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8

Feng, Wenli, Xuebin Lu, Jian Xiong, Zhihao Yu, Yilin Wang, Jianguo Cui, Rui Zhang y Rengui Weng. "Solid–Waste–Derived Geopolymer–Type Zeolite–like High Functional Catalytic Materials Catalyze Efficient Hydrogenation of Levulinic Acid". Catalysts 12, n.º 11 (4 de noviembre de 2022): 1361. http://dx.doi.org/10.3390/catal12111361.

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Three common solid wastes (waste incineration fly ash, sewage sludge, and polluted soil) were the raw materials used in the synthesis of a geopolymer–type zeolite–like product, which was then used as a catalyst carrier to prepare a nickel hydrogenation catalyst for the catalytic hydrogenation of levulinic acid to γ–valerolactone. Under optimum synthesis conditions, the synthesized geopolymer zeolite has excellent structure and performance. The characterization results show that the composites have a three–dimensional network structure, and the pore structure is homogeneous mesoporous or microporous. In this work, the results of catalytic hydrogenation show that the yield of γ–valerolactone can achieve up to 94% using the synthesized catalyst, which is comparable to that of commercial catalysts and the concentrations of typical polluting heavy metals of Cu, Zn, Pb, and Cd in the reaction solution were all below the emission concentration limit (Class I standard) after five cycles of reaction. In summary, this geopolymer–type zeolite–like catalyst is cheap and has excellent performance; it is, therefore, expected to be widely used in catalysis instead of commercial carriers.

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9

Kurta, Sergiy, Ihor Mykytyn, Victoria Ribun y Olga Khatsevich. "Features of the structure active centers of industrial catalysts for the oxidative chlorination of ethylene". International Journal of Engineering & Technology 7, n.º 2.23 (20 de abril de 2018): 307. http://dx.doi.org/10.14419/ijet.v7i2.23.12751.

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The active phase of CuCl2, HСuСl2, H2СuСl4 and two grades of industrial ethylene oxidation chlorination catalysts (EOC) such as deposited catalyst X1 (Harshow), with copper chlorides supported on an alumina surface, and a permeated MEDC-B catalyst immobilized in the internal pores of the firm of the company Sud-Chemie. Catalyst were analyzed by the method of thermoemission electronic raster (VEGA3NTSCAN) microscopy and X-ray fluorescence energy dispersion spectroscopy (EDX-7000). It is shown that the active catalyst centers of CuCl2 have different crystalline structure from the amorphous active phase of H2CuCl2, H2CuCl4 on the surface of the catalysts. On the surface of X1 Harshow copper chlorides are uniformly distributed throughout the volume of the carrier catalyst γ-Al2O3 in the form of amorphous portions [CuCl4]-2, [CuCl2]-1. At the same time, on the surface of the catalyst MEDC-B, the active centers have a separate cluster immobilized crystalline structure of the active phase, which differs from the composition of the carrier γ-Al2O3.

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10

Tian, Qingbin, Lansen Bi, Shuyan Lin, Jiangshan Gao y Yan He. "A review of cold plasma for catalyst synthesis and modification". Clean Energy Science and Technology 2, n.º 1 (29 de marzo de 2024): 131. http://dx.doi.org/10.18686/cest.v2i1.131.

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Cold plasma has been extensively studied and developed in the field of energy storage and conversion, with a focus on its ability to assist in catalyst synthesis, surface modification, the introduction of heteroatoms, the generation of defects and vacancies, the improvement of catalyst dispersion, and the reduction of particle size. In contrast to conventional calcination and chemical methods, the energy from cold plasma can be transferred directly to the catalyst and carrier during the treatment process, which can improve the interaction between the loaded catalyst and carrier by changing the internal structure and surface morphology of the catalyst. Therefore, these properties make cold plasma quite green, safe, and efficient for catalyst synthesis and modification. In this paper, the characteristics and applications of various cold plasma technologies, as well as the synergistic treatment of cold plasma technology with thermodynamic principles on catalysts, are analyzed. Based on current research progress, this paper provides a summary and outlook on the synthesis and modification of catalysts using cold plasma.

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11

Xu, Zhuang, Mengli Li, Guowang Shen, Yuhao Chen, Dashun Lu, Peng Ren, Hao Jiang, Xugen Wang y Bin Dai. "Solvent Effects in the Preparation of Catalysts Using Activated Carbon as a Carrier". Nanomaterials 13, n.º 3 (18 de enero de 2023): 393. http://dx.doi.org/10.3390/nano13030393.

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The role of solvents is crucial in catalyst preparation. With regard to catalysts prepared with activated carbon (AC) as the carrier, when water is used as a solvent it is difficult for the solution to infiltrate the AC. Because AC comprises a large number of C atoms and is a nonpolar material, it is more effective for the adsorption of nonpolar substances. Since the water and active ingredients are polar, they cannot easily infiltrate AC. In this study, the dispersion of the active component was significantly improved by optimizing the solvent, and the particle size of the active component was reduced from 33.08 nm to 15.30 nm. The specific surface area of the catalyst is significantly increased, by 10%, reaching 991.49 m2/g. Under the same reaction conditions, the conversion of acetic acid by the catalyst prepared with the mixed solvent was maintained at approximately 65%, which was 22% higher than that obtained using the catalyst prepared with water as the solvent.

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12

Shaimardan, E., S. K. Kabdrakhmanova, M. M. Beisebekov, B. S. Selenova, Zh Imangazinova y S. Sydykbayeva. "NICKEL NANOCATALYST FOR HYDRODECHLORINATION OF POLYCHLORINATED BIPHENYLS". NNC RK Bulletin, n.º 2 (6 de julio de 2023): 74–81. http://dx.doi.org/10.52676/1729-7885-2023-2-74-81.

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Currently, nanomaterials are an important class of materials in the field of synthesis of efficient and selective catalysts with desired properties due to their unique physical and chemical properties. The presence of nanosized particles of transition metals undoubtedly improves the course of the hydrodechlorination of polychlorinated biphenyls (PCBs) and makes it possible to reduce the content of the noble metal in the catalyst. In order to obtain active and stable heterogeneous catalysts for the neutralization of persistent organic pollutants (POPs), the correct choice of carrier and method of catalyst synthesis is required. In this work, the synthesis of a nickel nanocatalyst was carried out using the wet impregnation method for the hydrodechlorination of PCBs. Commercial activated carbon grade BAU-A was pre-modified with hydrochloric acid and used as a carrier (ACm) of the catalyst. Using modern physical and chemical methods, the main properties of the synthesized nanocatalyst were investigated. The IR spectroscopy has established that the carboxyl and carbonyl groups of ACm are the main functional groups that fix nickel in the bulk of the carrier. The nickel nanocatalyst has a developed surface, where nickel nanoparticles are deposited in micro- and mesopores of the carrier. The degree of conversion of 2,2',3,3',4-pentachlorobiphenyl is 84.21%, which indicates the catalytic activity of nickel nanocatalysts with respect to POPs.

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13

Farmanov, Behzod y Shakhzod Tavashov. "Processing of the catalyst used in reforming natural gas". E3S Web of Conferences 411 (2023): 01034. http://dx.doi.org/10.1051/e3sconf/202341101034.

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Today, in the world industry, special attention is paid to the synthesis of high-strength, low hydraulic resistance, improved geometry and increased specific surface area of catalyst granules. In this aspect an important task is to develop a technology for the production of our own highly efficient and durable catalysts based on the processing of spent industrial catalysts. To do this, it is necessary to substantiate a number scientific solutions, including in the following areas: development of technology for extracting nickel from spent industrial catalysts of the GIAP-8 series, technology for producing high-strength alumina carriers and scientific basis for obtaining a nickel-containing catalyst on a carrier of aluminum oxide.

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14

Song, Jialin, Ziliang Wang, Xingxing Cheng y Xiuping Wang. "State-of-Art Review of NO Reduction Technologies by CO, CH4 and H2". Processes 9, n.º 3 (23 de marzo de 2021): 563. http://dx.doi.org/10.3390/pr9030563.

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Removal of nitrogen oxides during coal combustion is a subject of great concerns. The present study reviews the state-of-art catalysts for NO reduction by CO, CH4, and H2. In terms of NO reduction by CO and CH4, it focuses on the preparation methodologies and catalytic properties of noble metal catalysts and non-noble metal catalysts. In the technology of NO removal by H2, the NO removal performance of the noble metal catalyst is mainly discussed from the traditional carrier and the new carrier, such as Al2O3, ZSM-5, OMS-2, MOFs, perovskite oxide, etc. By adopting new preparation methodologies and introducing the secondary metal component, the catalysts supported by a traditional carrier could achieve a much higher activity. New carrier for catalyst design seems a promising aspect for improving the catalyst performance, i.e., catalytic activity and stability, in future. Moreover, mechanisms of catalytic NO reduction by these three agents are discussed in-depth. Through the critical review, it is found that the adsorption of NOx and the decomposition of NO are key steps in NO removal by CO, and the activation of the C-H bond in CH4 and H-H bonds in H2 serves as a rate determining step of the reaction of NO removal by CH4 and H2, respectively.

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15

Fornalczyk, A., M. Kraszewski, J. Willner, J. Kaduková, A. Mrážiková, R. Marcinčáková y O. Velgosová. "Dissolution of Metal Supported Spent Auto Catalysts in Acids". Archives of Metallurgy and Materials 61, n.º 1 (1 de marzo de 2016): 233–36. http://dx.doi.org/10.1515/amm-2016-0043.

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Metal supported auto catalysts, have been used in sports and racing cars initially, but nowadays their application systematically increases. In Metal Substrate (supported) Converters (MSC), catalytic functions are performed by the Platinum Group Metals (PGM): Pt, Pd, Rh, similarly to the catalysts on ceramic carriers. The contents of these metals make that spent catalytic converters are valuable source of precious metals. All over the world there are many methods for the metals recovery from the ceramic carriers, however, the issue of platinum recovery from metal supported catalysts has not been studied sufficiently yet. The paper presents preliminary results of dissolution of spent automotive catalyst on a metal carrier by means of acids: H2SO4, HCl, HNO3, H3PO4. The main assumption of the research was the dissolution of base metals (Fe, Cr, Al) from metallic carrier of catalyst, avoiding dissolution of PGMs. Dissolution was the most effective when concentrated hydrochloric acid, and 2M sulfuric acid (VI) was used. It was observed that the dust, remaining after leaching, contained platinum in the level of 0.8% and 0.7%, respectively.

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16

Samotaev, Nikolay y Alexey Vasiliev. "Mixed Cerium/Zirconium Oxide as a Material for Carbon Monoxide Thermocatalytic Gas Sensor". Proceedings 2, n.º 13 (4 de diciembre de 2018): 841. http://dx.doi.org/10.3390/proceedings2130841.

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The perspective catalysts usable for the fabrication of thermocatalytic gas sensors were studied. The analysis of CO oxidation kinetics by Pd decorated Al2O3, ZSM-5, SnO2, CeO2/ZrO2 and some other carriers of catalysts showed that the application of these catalysts leads to the ambiguity of sensor response (light-off effect). It was demonstrated that a catalyst based on CeO2/ZrO2 carrier could be used for the fabrication of sensors characterized by the univocal correspondence between CO concentration and sensor response. The developed model of the CO oxidation on all Pd catalysts with inert carrier enabled the description of the CO oxidation using a single value of activation energy.

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Fornalczyk, Agnieszka, Slawomir Golak y Mariola Saternus. "Model of Infiltration of Spent Automotive Catalysts by Molten Metal in Process of Platinum Metals Recovery". Mathematical Problems in Engineering 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/461085.

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This paper presents the model for the washing-out process of precious metals from spent catalysts by the use of molten lead in which the metal flow is caused by the rotating electromagnetic field and the Lorentz force. The model includes the coupling of the electromagnetic field with the hydrodynamic field, the flow of metal through anisotropic and porous structure of the catalyst, and the movement of the phase boundary (air-metal) during infiltration of the catalyst carrier by the molten metal. The developed model enabled analysis of the impact of spacing between the catalysts and the supply current on the degree of catalyst infiltration by the molten metal. The results of calculations carried out on the basis of the model were verified experimentally.

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Guo, Jianping y Ping Chen. "Catalyst: NH3 as an Energy Carrier". Chem 3, n.º 5 (noviembre de 2017): 709–12. http://dx.doi.org/10.1016/j.chempr.2017.10.004.

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Li, Chengyang, Hongyi Li, Libo Zhang, Yubo Ma y Tianfu Wang. "Hydroformylation of Dicyclopentadiene to Monoformyltricyclodecenes over Supported Ultra-Low Content Rh Catalysts". Progress in Reaction Kinetics and Mechanism 43, n.º 2 (junio de 2018): 166–72. http://dx.doi.org/10.3184/146867818x15233705894356.

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Five types of 0.006 wt% Rh catalyst supported on the surfaces of Al2O3, ZnO, TiO2(rutile), TiO2(anatase) and CeO2 were prepared by the incipient wetness method and used to catalyse the conversion of dicyclopentadiene (DCPD) to monoformyltricyclodecenes (MFTD). The 0.006 wt% Rh/ZnO catalyst showed the highest performance of the catalysts investigated and a 95.5% MFTD yield with 100% MFTD selectivity could be achieved. This suggested that there may be a key role for the carrier on the catalytic performance in the DCPD hydroformylation. Furthermore, the kinetic profiles for DCPD hydroformylation over the 0.006 wt% Rh/ZnO catalyst have been examined systematically to explore the effect of reaction temperature on the catalytic performance. These data collectively suggested that a specific reaction temperature might enhance DCPD hydroformylation, possibly owing to agglomeration of the active sites at higher reaction temperatures.

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20

Iusovskii, Aleksei, Roman Boldushevskii, Aleksandr Mozhaev, Olga Shmelkova, Elizaveta Pavlycheva, Aleksandr Koklyukhin y Pavel Nikulshin. "Tailoring NiMo-Based Catalysts for Production of Low-Viscosity Sustainable Hydrocarbon Bases for Drilling Muds from Secondary Gas Oils". Energies 16, n.º 16 (8 de agosto de 2023): 5859. http://dx.doi.org/10.3390/en16165859.

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This article presents the prospect of using the process of deep hydrodesulfurization and hydrodearomatization of secondary gas oils using highly active NiMo catalysts to obtain hydrocarbon bases for drilling fluids. Catalysts were synthesized using PMo heteropolyanions, citric acid, and diethylene glycol on alumina carriers with different pore volumes. This study showed that the concentration of the impregnating solution affects the composition and morphology of the active phase particles of the prepared catalyst, while the textural characteristics of the carrier influence the physicochemical properties and catalytic activity of the NiMo/Al2O3 catalysts. The catalyst that was synthesized using a carrier with the largest pore volume and an effective diameter of more than 7 nm exhibited the highest activity. It was demonstrated that the use of such a catalyst allows for the procurement of hydrocarbon bases for drilling fluids from mixtures of secondary gas oils at a hydrogen pressure of 15–20 MPa. This study has practical significance for the development of sustainable and economically efficient methods for the utilization of low-quality petroleum gas oils to produce high-margin environmentally friendly non-fuel petroleum products, as well as contributes to the development of economically efficient technologies for the utilization of petroleum raw materials.

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Иванов, О. С., М. С. Василишин, А. Г. Карпов, А. А. Кухленко, Д. Б. Иванова y С. Е. Орлов. "PERFECTION of PREPARATION TECHNOLOGY of the CATALYST CARRIER". Южно-Сибирский научный вестник, n.º 6(40) (20 de diciembre de 2021): 43–49. http://dx.doi.org/10.25699/sssb.2021.40.6.031.

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Сибунит – носитель для катализатора, использующегося в различных процессах химической промышленности, в том числе и в реакции гидрирования. В настоящее время для его подготовки и проведения технологических операций используется так называемый «сухой» способ, обладающий обширными недостатками, основными из которых являются пыление, а также значительная доля ручного труда на производстве и, как следствие, большая продолжительность отдельных стадий.Предлагается использовать «мокрый» способ с применением аппаратуры роторно-пульсационного типа для подготовки носителя катализатора с целью исключения указанных недостатков.В результате проведённой работы было установлено, что активность образцов катализаторов, полученных с использованием молотковой мельницы и с применением роторно-пульсационного аппарата в реакции гидрогенолиза составила 0,606 моль/мин и 0,642 моль/мин, при выходе целевого продукта 76,15% и 80,00%, соответственно. Также определено, что доля потерь, обусловленная образованием пыли, была снижена более чем в 10 раз по сравнению с действующей технологией. Sibunit is carrying agent for the catalyst used in various processes of the chemical industry, including in hydrogenation reaction. Now for its preparation and conducting of technological operations the so-called "dry" way possessing extensive deficiencies is used, basic of which the fluffing, and also a considerable share of muscle work on manufacture and, as consequence, the big duration of separate stages are.It is offered to use a "wet" way with application of rotor-stator equipment for preparation of a catalyst carrier for the purpose of exclusion of the specified deficiencies.As a result of the spent work it has been established, that activity of the catalysts samples gained with use of the hammer mill and with application rotor-stator system in hydrogenation reaction has made 0,606 gramme-molecules/mines and 0,642 gramme-molecules/mines, at an yield of a target product of 76,15% and 80,00%, accordingly. Also it is defined, that the share of losses caused by a dust generation, it has been lowered more than in 10 times in comparison with acting technology.

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Yin, Min, Jin Chuan Gu, Zhi Jin Fan y Wei Zhao. "Research on the Preparation of Catalyst in Dealing with AR88 by CWAO". Advanced Materials Research 1092-1093 (marzo de 2015): 1046–50. http://dx.doi.org/10.4028/www.scientific.net/amr.1092-1093.1046.

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This article describes the research on the preparation of the catalyst which is used to deal with Acid Red 88 by catalytic wet oxidation. The experiment investigated the effect of catalyst carrier, impregnation and roast temperature etc on the catalytic activity. Found the optimal conditions to make catalyst finally, it can be described as follows: take lithium silicon powder as a carrier; 0.1mol /L iron nitrate as active ingredients to dip 20 hours; and then, calcined 90 minutes under the condition of 500°C. The removal rate of Acid Red 88 can reach up to 97.2% by the use of these catalysts after 60 minutes reaction.

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23

Yu, Lei, Min Song, Yuexing Wei y Jun Xiao. "Combining Carbon Fibers with Ni/γ–Al2O3 Used for Syngas Production: Part A: Preparation and Evaluation of Complex Carrier Catalysts". Catalysts 8, n.º 12 (13 de diciembre de 2018): 658. http://dx.doi.org/10.3390/catal8120658.

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To promote the adsorption and activation of carbon dioxide in the dry reforming of methane (DRM), Ni and Al2O3 were coprecipitated on activated carbon fibers (ACF). Various characterization methods were adopted in order to investigate the surface characteristics of different catalysts. Chemisorption characterization results, such as H2-temperature programmed reduction (H2-TPR), H2-temperature programmed desorption (H2-TPD), and CO2-temperature programmed desorption (CO2-TPD) illustrated that ACF in a nickel-based catalyst could enhance the basic sites and improve the metal dispersion on a catalyst surface, which is beneficial for the adsorption and activation of feed gas. The coprecipitated coating on ACF proved by scanning electron microscope (SEM) can prevent the carbon of ACF from participating in the reaction, while retain good surface properties of carbon fibers. X-ray diffraction (XRD) patterns illustrated that the ACF in a nickel-based catalyst could decrease the crystallite size of the spinel NiAl2O4, which is beneficial for methane reforming. In addition, the Fourier transform infrared spectroscopy (FTIR) of different catalysts revealed that the added ACF could provide abundant functional groups on the surface, which could be the intermediate product of DRM, and effectively promote the reaction. Different to the catalyst supported on single alumina, the performance evaluation and stability test proved that the catalyst added with ACF exhibited a better catalytic performance especially for CO2 conversion. Moreover, based on the characterization results as well as some related literature, the dry reforming mechanism over optimum catalyst was derived.

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24

L, Liu. "The Application of Mesoporous ZSM-5 Zeolite in the ULSD Catalysts". Petroleum & Petrochemical Engineering Journal 4, n.º 4 (2020): 1–3. http://dx.doi.org/10.23880/ppej-16000236.

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The mesoporous ZSM-5 zeolite containing MoCoP/Al2O3 catalyst (C12-ZSM5) with the mixture of Al2O3 and mesoporous ZSM- 5 zeolite as carrier was synthesized. The catalytic performance of C12-ZSM5 catalyst was evaluated by the hydrodesulfurization (HDS) of different diesel feedstock. The carriers and catalysts were characterized by N2 adsorption-desorption, pyridine-FTIR, X-ray diffraction (XRD) and CO in-situ FTIR (CO-FTIR) techniques. Results showed that mesoporous ZSM-5 can improve the acidity of the catalyst and increase the number of MoCoS active phases. The C12-ZSM5 catalyst had low HDS and HDN activity, because the acidic sites of mesoporous ZSM-5 were easily occupied by nitrogen compounds. The HDS activity of C12-ZSM5 catalyst was fully exploited by using graded packing technology, the sulfur content of product oil was 5.9 ng/μL. The relative HDS activity of C12-ZSM5 catalyst is 1.47 times that of FHUDS-8 catalyst.

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25

Lu, Xi Ning y Cun Yi Song. "The Study of the MnOx/TiO₂-ZrO₂ Used in the Sintering Flue Gas Low-Temperature Selective Catalytic Reaction". Advanced Materials Research 641-642 (enero de 2013): 551–56. http://dx.doi.org/10.4028/www.scientific.net/amr.641-642.551.

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TiO2, 50%TiO2-ZrO2 and 80%TiO2-ZrO2 were prepared by sol-gel method. The manganese oxides were impregnated on the carrier and the catalysts were used for low-temperature selective catalytic reduction of NOx with ammonia (NH3-SCR) in the presence of excess O2. The samples were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results showed that the particle size of 80%TiO2-ZrO2 is the smallest among the three kind of carrier and the particles are highly dispersed. By adding the ZrO2, the Zr4+ ions replaced the lattice Ti4+ ions, and thus caused lattice distortion in the TiO2 and an increase of the active point amount on the carrier. Furthermore, the Zr also promoted the dispersion of the active ingredients carried on the carrier, increased the surface concentration of Mn. The most active catalyst was obtained with a mass MnOx/80%TiO2-ZrO2 ratio of 0.1.The best MnOx/80%TiO2-ZrO2 catalyst yielded nearly 92.6% NO conversion at 130°C at a high space velocity of 67,000 h-1.

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26

Swearer, Dayne F., Hangqi Zhao, Linan Zhou, Chao Zhang, Hossein Robatjazi, John Mark P. Martirez, Caroline M. Krauter et al. "Heterometallic antenna−reactor complexes for photocatalysis". Proceedings of the National Academy of Sciences 113, n.º 32 (21 de julio de 2016): 8916–20. http://dx.doi.org/10.1073/pnas.1609769113.

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Metallic nanoparticles with strong optically resonant properties behave as nanoscale optical antennas, and have recently shown extraordinary promise as light-driven catalysts. Traditionally, however, heterogeneous catalysis has relied upon weakly light-absorbing metals such as Pd, Pt, Ru, or Rh to lower the activation energy for chemical reactions. Here we show that coupling a plasmonic nanoantenna directly to catalytic nanoparticles enables the light-induced generation of hot carriers within the catalyst nanoparticles, transforming the entire complex into an efficient light-controlled reactive catalyst. In Pd-decorated Al nanocrystals, photocatalytic hydrogen desorption closely follows the antenna-induced local absorption cross-section of the Pd islands, and a supralinear power dependence strongly suggests that hot-carrier-induced desorption occurs at the Pd island surface. When acetylene is present along with hydrogen, the selectivity for photocatalytic ethylene production relative to ethane is strongly enhanced, approaching 40:1. These observations indicate that antenna−reactor complexes may greatly expand possibilities for developing designer photocatalytic substrates.

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27

Xu, Jun Qiang, Fang Guo, Jun Li y Xue Jun Quan. "Preparation of the Modified Mesoporous Beta Materials and its Application in Wet Catalytic Degradation of Methyl Orange". Advanced Materials Research 393-395 (noviembre de 2011): 1381–84. http://dx.doi.org/10.4028/www.scientific.net/amr.393-395.1381.

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The heterogeneous beta-supported transition metal catalysts were prepared by incipient wetness impregnation. The catalytic oxidation degradation of methyl orange was carried over the heterogeneous catalyst in the peroxide catalytic oxidation process. The pure beta materials showed quick adsorption equilibrium characterization, and the adsorption ratio was only 30%. Compared with the adsorption of the pure beta carrier, the Cu/beta and Fe/beta catalyst could effectively degrade methyl orange with high catalytic activity and easy catalyst separation from the solution using hydrogen peroxide as oxide. The methyl orange removal efficiency could reach 99% in the optimum experimental conditions. The optimal mental content for Cu, Ag, Mn, Fe and Co was 5%, 8%, 0.3%, 1% and 0.3%, respectively.

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28

Tungatarova, Svetlana, Galina Xanthopoulou, George Vekinis, Konstantinos Karanasios, Tolkyn Baizhumanova, Manapkhan Zhumabek y Marzhan Sadenova. "Ni-Al Self-Propagating High-Temperature Synthesis Catalysts in Dry Reforming of Methane to Hydrogen-Enriched Fuel Mixtures". Catalysts 12, n.º 10 (18 de octubre de 2022): 1270. http://dx.doi.org/10.3390/catal12101270.

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The worldwide increase in demand for environmentally friendly energy has led to the intensification of work on the synthesis of H2-containing fuel. The dry reforming of methane has become one of the most important avenues of research since the consumption of two greenhouse gases reduces the rate of global warming. A study of NiAl composite materials as catalysts for methane reforming has been carried out. Self-propagating high-temperature synthesis (SHS) has been used to produce NiAl catalysts. Comparative studies were carried out regarding the dry reforming and partial oxidation of methane, as well as catalysts prepared using the impregnation (IM) and SHS methods. A catalyst with 29% Ni and 51% Al after SHS contains the phases of NiAl and NiAl2O4, which are active phases in the dry reforming of methane. The optimal crystal lattice parameter (for the maximum possible conversion of CO2 and CH4) is 3.48–3.485 Å for Al2O3, which plays the role of a catalyst carrier, and 1.42 Å, for NiAl2O4, which plays the role of a catalyst. The aim of the work is to develop a new and efficient catalyst for the dry reforming of methane into a synthesis gas, which will further promote the organization of a new era of environmentally friendly energy-saving production methods.

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Li, Chengyang, Libo Zhang, Yubo Ma y Tianfu Wang. "Nanopowder-Supported Ultra-Low Content Co–Rh Bimetallic Catalysts for Hydroformylation of Monoformyltricyclodecenes to Value-Added Fine Chemicals". Progress in Reaction Kinetics and Mechanism 43, n.º 3-4 (octubre de 2018): 254–61. http://dx.doi.org/10.3184/146867818x15319903829173.

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The hydroformylation of monoformyltricyclodecenes (MFTD) to diformyltricyclodecanes (DFTD) was studied systematically. A series of 0.006 wt% Rh–0.006 wt% Co catalysts supported on commercially available nanopowders such as Al2O3, ZnO, TiO2 and CeO2 was prepared by the incipient wetness method and used to catalyse the hydroformylation of MFTD to DFTD. The 0.006 wt% Rh–0.006 wt% Co/ZnO catalyst showed the highest catalytic performance among the catalysts investigated, thus 41.8% DFTD yield with 100% DFTD selectivity could be achieved. This suggested that there may be a key role of the carrier on the catalytic performance in MFTD hydroformylation. Furthermore, the kinetic profiles for MFTD hydroformylation over the 0.006 wt% Rh–0.030 wt% Co/ZnO catalyst have been examined systematically to explore the effect of reaction temperature on the catalytic performance. These results collectively suggested that a particular reaction temperature might benefit MFTD hydroformylation. There may be some agglomeration of the active sites at higher reaction temperatures.

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30

Glikin, M. A., I. M. Glikina y E. Kauffeldt. "Investigations and Applications of Aerosol Nano-Catalysis in a Vibrofluidized (Vibrating) Bed". Adsorption Science & Technology 23, n.º 2 (marzo de 2005): 135–43. http://dx.doi.org/10.1260/0263617054037781.

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Factors influencing changes in the properties of catalyst surfaces at decreasing particulate (particle) size down to 100 nm and finer were described. The potential properties of carrier-based nano-catalysts, such as their activity, strength and thermal resistance, have been analyzed and the advantages of employing aerosol nano-catalysts (AC) without carriers but possessing nano-sized particulates (particles) discussed. Experimental data on AC obtained for a fluidized bed wherein different classes of reactions were undertaken for an optimal concentration of nano-particle catalysts (4–10 g/m3 of the reaction volume) were described. Some experimental data obtained for a new AC variant involving a vibrofluidized (vibrating) bed were examined. Decreasing the optimal catalyst concentration to less than 1 g/m3 of the reaction volume tripled the product yield per cubic metre.

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31

Zhang, Jinxu, Fusheng Yang, Bin Wang, Dong Li, Min Wei, Tao Fang y Zaoxiao Zhang. "Heterogeneous Catalysts in N-Heterocycles and Aromatics as Liquid Organic Hydrogen Carriers (LOHCs): History, Present Status and Future". Materials 16, n.º 10 (15 de mayo de 2023): 3735. http://dx.doi.org/10.3390/ma16103735.

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The continuous decline of traditional fossil energy has cast the shadow of an energy crisis on human society. Hydrogen generated from renewable energy sources is considered as a promising energy carrier, which can effectively promote the energy transformation of traditional high-carbon fossil energy to low-carbon clean energy. Hydrogen storage technology plays a key role in realizing the application of hydrogen energy and liquid organic hydrogen carrier technology, with many advantages such as storing hydrogen efficiently and reversibly. High-performance and low-cost catalysts are the key to the large-scale application of liquid organic hydrogen carrier technology. In the past few decades, the catalyst field of organic liquid hydrogen carriers has continued to develop and has achieved some breakthroughs. In this review, we summarized recent significant progress in this field and discussed the optimization strategies of catalyst performance, including the properties of support and active metals, metal–support interaction and the combination and proportion of multi-metals. Moreover, the catalytic mechanism and future development direction were also discussed.

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32

Zhou, Jie, Xin Zhao, Haoming Xu, Zhichao Wang, Xiaoyuan Zhang y Zhiqiang Su. "Integration of Carbon Dots on Nanoflower Structured ZnCdS as a Cocatalyst for Photocatalytic Degradation". Materials 16, n.º 1 (30 de diciembre de 2022): 366. http://dx.doi.org/10.3390/ma16010366.

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The application of catalysts is one of the most effective methods in the oil refining, chemical, medical, environmental protection, and other industries. In this work, carbon dots (CDs) were selected as an initiator and doped into the main catalyst, Zn0.2Cd0.8S, and a novel Zn0.2Cd0.8S@CD composite catalyst with a nanoflower structure was successfully obtained. The synthesized composites (Zn0.2Cd0.8S@CDs) were characterized by means of SEM, TEM, XRD, FT-IR, XPS, and UV-Vis DRS. Transient photocurrent response and Nyquist curve analysis further proved that the carrier separation efficiency of the composite catalyst was significantly improved. In addition, the photocatalytic activity of Zn0.2Cd0.8S@CDs for rhodamine B removal from aqueous solution was tested under visible-light irradiation. When the amount of Zn0.2Cd0.8S@CDs composite catalyst reached 50 mg, the degradation rate of rhodamine B was 79.35%. Finally, the photocatalytic degradation mechanism of the Zn0.2Cd0.8S@CDs complex was studied. CD doping enhances the adsorption capacity of Zn0.2Cd0.8S@CDs composite catalysts due to the increase in surface area, effectively inducing charge delocalization and enhancing the photocatalytic capacity. Zn0.2Cd0.8S@CDs composites with low cost and high carrier separation efficiency have broad application prospects in the photocatalytic degradation of dyes.

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33

Li, Luming, Song Wu, Hongmei Li, Jie Deng y Junshan Li. "Preparation of Novel Mesoporous LaFeO3-SBA-15-CTA Support for Syngas Formation of Dry Reforming". Nanomaterials 12, n.º 9 (24 de abril de 2022): 1451. http://dx.doi.org/10.3390/nano12091451.

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A nanocomposite NiPt/5LSBA-160 catalyst comprised of highly dispersed Ni nanoparticles contacting intimately with Pt over novel mesoporous LaFeO3-SBA-15-CTA support with a high specific surface area (SSA) was successfully developed for the dry reforming of methane. Results revealed that the high SSA mesoporous LaFeO3-SBA-15-CTA materials could first be synthesized by an in situ growth hydrothermal process and used as an excellent carrier candidate of Ni-based catalysts to achieve enhanced catalytic activity due to the strong interaction between LaFeO3 and Ni species. Moreover, the introduction of Pt over a Ni/5LSBA-160 catalyst would further promote the interaction between Ni and support, improve the dispersion of active Ni centers and obtain a higher syngas formation rate as well as tolerance to carbon coking than that of a Pt-free Ni/5LSBA-160 catalyst sample. This finding uncovers a promising prospect for high SSA mesoporous perovskite preparation and utilization in catalysis such as oxidation, hydrogenation, photocatalysis, energy conversion and so on.

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34

Li, Luming, Song Wu, Hongmei Li, Jie Deng y Junshan Li. "Preparation of Novel Mesoporous LaFeO3-SBA-15-CTA Support for Syngas Formation of Dry Reforming". Nanomaterials 12, n.º 9 (24 de abril de 2022): 1451. http://dx.doi.org/10.3390/nano12091451.

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A nanocomposite NiPt/5LSBA-160 catalyst comprised of highly dispersed Ni nanoparticles contacting intimately with Pt over novel mesoporous LaFeO3-SBA-15-CTA support with a high specific surface area (SSA) was successfully developed for the dry reforming of methane. Results revealed that the high SSA mesoporous LaFeO3-SBA-15-CTA materials could first be synthesized by an in situ growth hydrothermal process and used as an excellent carrier candidate of Ni-based catalysts to achieve enhanced catalytic activity due to the strong interaction between LaFeO3 and Ni species. Moreover, the introduction of Pt over a Ni/5LSBA-160 catalyst would further promote the interaction between Ni and support, improve the dispersion of active Ni centers and obtain a higher syngas formation rate as well as tolerance to carbon coking than that of a Pt-free Ni/5LSBA-160 catalyst sample. This finding uncovers a promising prospect for high SSA mesoporous perovskite preparation and utilization in catalysis such as oxidation, hydrogenation, photocatalysis, energy conversion and so on.

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35

Guo, Xiuling, Jihai Duan, Chaojie Li, Zisheng Zhang y Weiwen Wang. "Modified bamboo-based activated carbon as the catalyst carrier for the gas phase synthesis of vinyl acetate from acetylene and acetic acid". International Journal of Chemical Reactor Engineering 19, n.º 4 (18 de febrero de 2021): 331–40. http://dx.doi.org/10.1515/ijcre-2020-0196.

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Abstract As a significant component of catalyst system, catalyst carrier can impact on coating amount of active component, and in turn catalytic activity. In this work, study of bamboo-based activated carbon as the catalyst carrier for gas phase synthesis of vinyl acetate from acetylene and acetic acid was carried out. Characterization and experimental results showed that bamboo-based activated carbon possessed the conditions and potential of being a catalyst carrier and characterized a greater advantage in structure and properties after modification. After ultrasonic treatment, it was found that the mesoporous distribution of activated carbon increased, which promoted the adsorption to zinc acetate and resulted in 23% increase in productivity of catalyst. Simultaneously, it had a different effect on surface area and pore-size distribution of activated carbon by thermal treatment at high temperatures in N2 and CO2 atmosphere. The productivity of catalyst with bamboo-based activated carbon as catalyst carrier after thermal treatment in N2 and CO2 can be increased by 14 and 20%, respectively. Furthermore, based on the influence of pore size on adsorption and reaction of active components, the necessity of expanding pores of carbon was explained in this paper, which pointed out the direction of activated carbon modification.

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36

Pavliuk, N. S., V. V. Ivasiv, O. M. Orobchuk, D. S. Shevchenko y R. V. Nebesnyi. "Kinetics of aldol condensation of acetic acid with formaldehyde on B–P–V–W–OX/SiO2 catalyst". Chemistry, Technology and Application of Substances 3, n.º 2 (1 de noviembre de 2020): 39–45. http://dx.doi.org/10.23939/ctas2020.02.039.

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New catalysts B–P–V–W–Ox/SiO2 of gas-phase condensation of acetic acid from formaldehyde to acrylic acid on an industrial carrier of stable chemical composition (colloidal silicon oxide, Aerosil A-200) were synthesized. It is shown that the hydrothermal treatment of the carrier allows to increase the activity and selectivity of the catalyst in the reactions of aldol condensation of acetic acid with formaldehyde. It was found that the developed catalyst is effective in the condensation reaction of acetic acid with formaldehyde, which allows to obtain acrylic acid with a yield of 68.7% and a selectivity of 94.1%. The kinetic regularities of the reaction on this catalyst are established. According to the proposed kinetic equations, kinetic parameters are calculated that describe the condensation reaction of acetic acid with formaldehyde.

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37

Li, Guobo, Weiwei Feng, Yiwei Luo, Jie Yan, Yining Cai, Yiling Wang, Shule Zhang, Wenming Liu y Honggen Peng. "Unraveling FeOx Nanoparticles Confined on Fibrous Mesoporous Silica Catalyst Construction and CO Catalytic Oxidation Performance". Catalysts 14, n.º 1 (14 de enero de 2024): 63. http://dx.doi.org/10.3390/catal14010063.

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Catalytic oxidation is used to control carbon monoxide (CO) emissions from industrial exhaust. In this study, a mesoporous silica material, KCC-1, was synthesized and used as a carrier with a high specific surface area to confine active component FeOx nanoparticles (NPs), and the CO catalytic oxidation performance of x%Fe@KCC-1 catalysts (x represents the mass loading of Fe) was studied. The experimental results showed that due to its large specific surface area and abundant mesopores, the FeOx NPs were highly dispersed on the surface of the KCC-1 carrier. The particle size of FeOx was very small, resulting in strong interactions between FeOx NPs and KCC-1, which enhanced the catalytic oxidation reaction on the catalyst. The FeOx loading improved the CO adsorption capability of the catalyst, which facilitated the catalytic oxidation of CO, with the 7%Fe@KCC-1 catalyst achieving 100% CO conversion at 160 °C. The CO catalytic removal mechanism was investigated by a combination of in-situ DRIFTS and DFT calculations. This study advances scientific understanding of the application potential of nano-catalysts in important oxidation reactions and provides valuable insights into the development of efficient CO oxidation catalysts.

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38

Gou, Xiang, Kai Zhang, Lian Sheng Liu, Wen Yong Liu, Zi Fang Wang, Guang Yang, Jin Xiang Wu y En Yu Wang. "Study on Noble Metal Catalyst for Selective Catalytic Reduction of NOx at Low Temperature". Applied Mechanics and Materials 448-453 (octubre de 2013): 885–89. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.885.

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The method of selective catalytic reduction (SCR) to removal NOx is very mature. However, its initial investment and operation cost are still high, which limits the development of SCR technology. Low temperature SCR catalysts can significantly reduce the cost. Catalyst active component and its carrier is the key to the efficiency of denitration. This paper summarizes the research progress of noble metal catalyst of low temperature SCR.

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39

Dönmez, Fahriye, Burcu Kiren y Nezihe Ayas. "Investigation of Hydrogen Production from Sodium Borohydride in the Presence of Ni/Al₂O₃". IOP Conference Series: Earth and Environmental Science 1050, n.º 1 (1 de julio de 2022): 012012. http://dx.doi.org/10.1088/1755-1315/1050/1/012012.

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Abstract With the increasing trend towards the use of renewable energy and the encouragement of international agreements due to environmental effects, the world tends to provide the energy it needs from renewable sources. Hydrogen is an environmentally friendly energy carrier that is produced from various energy sources and can be a sustainable solution to energy needs. Catalyst evaluation studies are carried out in studies that release high purity hydrogen by hydrolysis of metal hydrides such as sodium borohydride (NaBH4), and potassium borohydride (KBH4). In this study, Al2O3 supported Ni catalysts were synthesized by the impregnation method and the catalysts were characterized by applying X-Ray Diffractometry (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM), and Brunauer-Emmett-Teller (BET) methods. The performance of the catalysts was evaluated in the production of hydrogen by the hydrolysis of sodium borohydride. The influences of reaction temperature (20, 40, and 60 °C) and Ni content of the catalyst (20, 30, and 40 %) on the hydrolysis reaction was investigated under experimental conditions of 100 mg NaBH4, 100 mg catalyst, 5 mL 0.25 M NaOH. The highest hydrogen yield (100%) and hydrogen production rate (364.3 mL/gcat.min) was obtained with 40% Ni/Al2O3 catalyst at 60 °C reaction temperature.

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40

Shao, Jiaming, Yunchu Zhai, Luyang Zhang, Li Xiang y Fawei Lin. "Low-Temperature Catalytic Ozonation of Multitype VOCs over Zeolite-Supported Catalysts". International Journal of Environmental Research and Public Health 19, n.º 21 (4 de noviembre de 2022): 14515. http://dx.doi.org/10.3390/ijerph192114515.

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Volatile organic compounds (VOCs) are an important source of air pollution, harmful to human health and the environment, and important precursors of secondary organic aerosols, O3 and photochemical smog. This study focused on the low-temperature catalytic oxidation and degradation of benzene, dichloroethane, methanethiol, methanol and methylamine by ozone. Benzene was used as a model compound, and a molecular sieve was selected as a catalyst carrier to prepare a series of supported active metal catalysts by impregnation. The effects of ozone on the catalytic oxidation of VOCs and catalysts’ activity were studied. Taking benzene as a model compound, low-temperature ozone catalytic oxidation was conducted to explore the influence of the catalyst carrier, the active metal and the precious metal Pt on the catalytic degradation of benzene. The optimal catalyst appeared to be 0.75%Pt–10%Fe/HZSM(200). The catalytic activity and formation of the by-products methylamine, methanethiol, methanol, dichloroethane and benzene over 0.75%Pt–10%Fe/HZSM(200) were investigated. The structure, oxygen vacancy, surface properties and surface acidity of the catalysts were investigated. XRD, TEM, XPS, H2-TPR, EPR, CO2-TPD, BET, C6H6-TPD and Py-IR were combined to establish the correlation between the surface properties of the catalysts and the degradation activity.

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41

Azizi, Nor, Young Kwang Kim, Jin Miyawaki, Isao Mochida y Seong Ho Yoon. "Low Temperature Catalytic Steam Gasification of Waste Palm Trunk by Pottasium Carbonate Supported on Perovskite Oxide". Advanced Materials Research 626 (diciembre de 2012): 551–58. http://dx.doi.org/10.4028/www.scientific.net/amr.626.551.

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A waste palm trunk was used as raw materials of derived biochar in catalytic steam gasification experiments. Pre-treatment was done to enrich the carbon content and removed the heavy and light tar. Waste palm trunk has been added in pyrolysis reactor to produce biochar at temperature 550°C under N2 flow. The experimental ran in a bubbling fluidized reactor at atmospheric pressure by the steam as gasification agent and Nitrogen as a carrier gas with different catalysts such as K2CO3 / LaMn0.8Cu0.2, K2CO3 / Alumina, Alumina and K2CO3 respectively. The experiments have been carried out to investigate the effect of gasification temperature, effect of catalyst and effect of catalyst ratio to biochar on the carbon conversion into syngas. The syngas compositions were analyzed by gas chromatography. K2CO3 / LaMn0.8Cu0.2 catalyst showed the better carbon conversion as compared to the other catalysts. Perovskite oxide was more effective as a support for the gasification catalyst. The results showed that the better carbon conversion ratio within short time gasification and removed heavy and light tar. K2CO3 / LaMn0.8Cu0.2 showed high activity for biochar gasification at low temperature and good recovery property near 750°C.

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42

Liu, Lin, Yucheng Fang, Rongyi Gao y Jianfen Li. "Optimization of Ni/ZnZr catalyst for enhanced syngas yield in catalytic pyrolysis of rice straw". BioResources 18, n.º 4 (18 de septiembre de 2023): 7524–38. http://dx.doi.org/10.15376/biores.18.4.7524-7538.

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To enhance the catalytic performance of nickel-based catalysts and improve their efficiency in biomass pyrolysis, a nickel-based catalyst supported on a ZnZr composite carrier was synthesized using the sol-gel method. The morphological changes of the catalyst before and after the reaction were observed using X-ray diffraction, scanning electron microscopy, nitrogen gas adsorption, temperature-programmed reduction, and other methods to analyze its catalytic performance. A series of experiments were conducted to explore the optimal conditions for the catalyst’s gas production, including carrier material ratios, loading amounts, residence time, and reaction temperature. The bimetallic carrier of Zn and Zr provided a higher specific surface area, allowing the metallic nickel to enter its mesopores. The synergistic effect of the bimetallic system facilitated the catalytic activity of nickel, significantly enhancing gas production. The maximum CO and H2 production were achieved at Zn/Zr = 6/4. The catalyst achieved an optimal gas yield of 507 mL/g at a residence time of 20 min and a reaction temperature of 800 °C, demonstrating strong stability.

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Wang, Anping, Wenxuan Quan y Heng Zhang. "Efficient Synthesis of Biodiesel Catalyzed by Chitosan-Based Catalysts". International Journal of Chemical Engineering 2021 (29 de diciembre de 2021): 1–11. http://dx.doi.org/10.1155/2021/8971613.

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Catalysts play an important role in the preparation of biodiesel. It is of great significance to study catalysts with high efficiency, low cost, and easy preparation. Compared with the homogeneous catalyst system, the heterogeneous catalyst is easy to separate and has a better catalytic effect. In heterogeneous catalysts, supports and preparation methods have important effects on the dispersion of active centers and the overall performance of catalysts. However, the supports of existing solid catalysts have defects in porosity, structural uniformity, stability, and specific surface area, and the preparation methods cannot stabilize covalent bonds or ionic bonds to bind catalytic sites. Considering the activity, preparation method, and cost of the catalyst, biomass-based catalyst is the best choice, but the specific surface area of the biomass-based catalyst is relatively low, the distribution of active centers is uneven, and it is easy to lose. Therefore, the hybrid carrier of biomass-based catalyst and other materials can not only improve the specific surface area but also make the distribution of active centers uniform and the catalytic activity better. Based on this, we summarized the application of chitosan hybrid material catalysts in biodiesel. The preparation, advantages and disadvantages, reaction conditions, and so on of chitosan-based catalysts were mainly concerned. At the same time, exploring the effects of different types of chitosan-based catalysts on the preparation of biodiesel and exploring the process technology with high efficiency and low consumption is the focus of this paper.

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Zhang, Xue Mei y Feng Xing Niu. "Liquid-Phase Hydrogenation to 2, 4-Tolylenediamine over Supported HY Catalysts". Advanced Materials Research 512-515 (mayo de 2012): 2381–85. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.2381.

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We have successfully prepared a novel passivation Ni/HY catalyst by the technologies of macerate-precipitatio.The catalysts are comprised of two contents: HY as carrier, Ni as active component，and we put it into the process of preparating aromatic amines.The nature of the catalysts was discussed based on the characterization results of BET , IR , SEM , XRD , TEM ,TPD , XPS and TPR . The catalytic hydrogenation technology for 2,4-dinitrobenzene in liquid phase can be an attractive and elegant routine for production of 2,4-tolylenediamine. The catalytic activity is evaluated at 2.2 MPa, 90 °C, 750r/min, solvent with reaction materials mass ratio of 60, catalyst with reaction materials mass ratio of 0.1. In the catalytic test, The experimental results over the catalyst showed that 2,4-dinitrobenzene and 2,4-tolylenediamine conversion and selective of 99.88% and 99.16% were obtained respectively.It is found that the catalyst is highly dispersion, stable, and reusable. No obvious deactivation of the catalyst was observed after repeated using twelve times.

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Wang, Xiao, Fei Zhao, Nan Zhang, Wenli Wu y Yuhua Wang. "Hollow Spherical Pd/CdS/NiS with Carrier Spatial Separation for Photocatalytic Hydrogen Generation". Nanomaterials 13, n.º 8 (10 de abril de 2023): 1326. http://dx.doi.org/10.3390/nano13081326.

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Inspired by the unique properties of the three-dimensional hollow nanostructures in the field of photocatalysis, as well as the combination of co-catalyst, porous hollow spherical Pd/CdS/NiS photocatalysts are prepared by stepwise synthesis. The results show that the Schottky junction between Pd and CdS accelerates the transport of photogenerated electrons, while a p-n junction between NiS and CdS traps the photogenerated holes. As co-catalysts, the Pd nanoparticles and the NiS are loaded inside and outside the hollow CdS shell layer, respectively, which combines with the particular characteristic of the hollow structure, resulting in a spatial carrier separation effect. Under the synergy of the dual co-catalyst loading and hollow structure, the Pd/CdS/NiS has favorable stability. Its H2 production under visible light is significantly increased to 3804.6 μmol/g/h, representing 33.4 times more than that of pure CdS. The apparent quantum efficiency is 0.24% at 420 nm. A feasible bridge for the development of efficient photocatalysts is offered by this work.

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Xin, XU, DONG Xufeng, HUANG Hao y QI Min. "3D Nitrogen-Doped Porous Carbon Supported Pt Catalyst for Electrocatalytic Oxidation of Glucose". Progress in Chinese Materials Sciences 2, n.º 3 (28 de septiembre de 2023): 41–49. http://dx.doi.org/10.48014/pcms.20230403001.

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Glucose fuel cells have attracted widespread attention in the biomedical field due to their ability to generate electrical energy continuously. The development of this technology has great potential in the application of powering implantable medical devices. However, the efficiency of the glucose oxidation reaction at the anode of the fuel cell is low, and a catalyst needs to be added to improve the reaction efficiency. Platinum (Pt) catalysts are prone to agglomerate during use, which limits the improvement of their properties such as catalytic activity and stability. To address this problem, in this paper, a three-dimensional ( 3D) N-doped porous carbon (NCZIF-8) material with a large specific surface area was prepared as a catalyst carrier using ZIF-8 as a precursor. Low loading rate of platinum (10 wt. %) was prepared (10% Pt/NCZIF-8) and used as catalysts for glucose oxidation reaction. The materials were structurally characterized by XRD, SEM, TEM, Raman and FT-IR, etc. The electrocatalytic properties of the materials were characterized using an electrochemical workstation. It was shown that the incorporation of NCZIF-8 carrier promotes the dispersion of Pt nanoparticles (NPs) and the utilization of the catalyst, which enhances the catalytic activity and stability of catalysts during electrocatalytic glucose oxidation. After 300 times cyclic voltammetry (CV) tests, the peak current density of 10% Pt/NCZIF-8 only decreased by 21. 12% and 8. 59% in the double-layer region and oxygen region, respectively, indicating the excellent stability of the catalyst. This kind of catalyst with low loading rate of precious metal has great potential for its practical application by improving catalyst utilization, which not only improves the catalytic efficiency but also reduces the material cost.

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Kang, Jianli, Jiajun Li, Naiqin Zhao, Philip Nash, Chunsheng Shi y Ronglu Sun. "Study of Mg Powder as Catalyst Carrier for the Carbon Nanotube Growth by CVD". Journal of Nanomaterials 2011 (2011): 1–6. http://dx.doi.org/10.1155/2011/938493.

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The possibility of using magnesium powder as catalyst carrier for carbon nanotube growth by chemical vapor deposition, which may pave a new way to in situ fabricate CNT/Mg composites with high CNT dispersion, was investigated for the first time. The fabrication process of the catalyst supported on Mg powder involves the preparation of colloid by a deposition-precipitation method, followed by calcination and reduction. The results show that the interaction between catalyst and support plays an important role for the catalytic property of the catalyst. Ni alloyed with Mg shows no activity for the decomposition of methane. The introduction of Y in Ni/Mg catalyst can promote the reaction temperature between Ni and Mg and thus enhance the activity of the catalyst. A large amount of carbon nanotubes (CNTs) with an average diameter of 20 nm was obtained using Ni/Y/Mg catalyst at450∘C, while only a few short CNTs were obtained using Ni/Mg catalyst due to the low activity of the catalyst at lower temperature.

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Kurunina, G. M., O. M. Ivankina y G. M. Butov. "Hydrogenation of Nitro Compounds over Catalytic Systems Containing Rare-Earth Oxides". Solid State Phenomena 316 (abril de 2021): 684–88. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.684.

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The paper studies the activity of 1 % palladium catalysts containing rare earth oxides (REOs) and alumina as a carrier in the hydrogenation of nitro compounds exemplified by nitrobenzene and o-nitro anisole. Under the liquid-phase hydrogenation conditions, these catalytic systems provide high selectivity of the process and a quantitative yield. It has been found that the partial replacement of Al2O3 with REO allows increasing the hydrogenation rate by 5–6 times, as compared with the reference catalyst and by 1.2–1.7 times as compared with the individual carrier. The oxide mixtures (REO and Al2O3) containing 20–40 % REO allow reaching the same hydrogenation rate with that over an REO-containing 1 % Pd catalyst.

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Trambouze, Pierre. "Structuring Information and Entropy: Catalyst as Information Carrier". Entropy 8, n.º 3 (16 de junio de 2006): 113–30. http://dx.doi.org/10.3390/e8030113.

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崔, 晗. "Orthogonal Design of the Hydrophobic Catalyst Carrier SDB". Nuclear Science and Technology 07, n.º 03 (2019): 114–22. http://dx.doi.org/10.12677/nst.2019.73016.

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