Article
Chemistry, Physical
S. Humbert, E. Devers, C. Lesage, C. Legens, L. Lemaitre, L. Sorbier, F. De Geuser, V. Briois
Summary: Increasing the molybdenum content in sulfide catalysts can improve their activity, with the distribution of MoS2 particles playing a crucial role. Anomalous Small-Angle X-ray Scattering (ASAXS) has been used to analyze the microstructural organization of the molybdenum active phase, revealing the impact of additives and sulfidation conditions on catalytic performance. The study demonstrates the potential of ASAXS in providing detailed insights on the multi-scale organization of the active phase.
JOURNAL OF CATALYSIS
(2021)
Article
Engineering, Chemical
Yongde Ma, Jiayin Zhang, Wenquan Wu, Zhenping Cai, Yanning Cao, Kuan Huang, Lilong Jiang
Summary: In this study, trialkylmethylammonium molybdate ionic liquids (ILs) with multiple long-chain alkyl groups were designed and applied as the oil-soluble precursors of dispersed metal catalysts for slurry-phase hydrocracking. The performance and sulfidation behavior of molybdate ILs were characterized, and the different performance of oil-soluble precursors was explained by isolating and characterizing the dispersed MoS2 catalysts. The performance of molybdate ILs for slurry-phase hydrocracking of heavy oils was investigated, and the favored routes for the conversion of heavy oils were determined based on reaction rate constants calculated from a kinetical model.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
F. Saenz, Z. Sun, A. E. Fisher, B. Wynne, E. Kolemen
Summary: The 'divertorlets' concept is a potential solution for heat removal at low recycling regime in the form of non-evaporative liquid metal. A toroidal divertorlets prototype was built and tested to evaluate its performance, and the results were compared with analytical theory and MHD numerical simulations. The experiments, analytical model, and simulations showed agreement, demonstrating the concept's feasibility for divertor applications at higher magnetic flux densities.
Article
Engineering, Chemical
Zareta M. Matieva, Natalia Kolesnichenko, Yulia M. Snatenkova, Alexander A. Panin, Anton L. Maximov, A. V. Topchiev
Summary: This study demonstrated the direct conversion of CO2 to liquid hydrocarbons using a combination of CuZnAl/Al2O3 and Zn-HZSM-5 catalysts. The best performance was achieved with a CuZnAl-Al2O3/Zn-HZSM-5 physical mixture catalyst in a 1:1 weight ratio. Under specific experimental conditions, the CO2 conversion rate was 20%, with a selectivity of 47% for C5+ hydrocarbons (78% based on total hydrocarbons), and a selectivity of methane below 2%.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2023)
Article
Energy & Fuels
Mohammed Al-Ani, Muthanna Al-Dahhan
Summary: An experimental study was conducted to investigate the hydrodynamics in TBR with different industrial catalyst beds of spherical, cylindrical, trilobe, and quadrilobe shapes. The results showed a significant impact of catalyst shape, gas flow rate, and liquid flow rate on the pressure drop and liquid holdup. The comparison between data and models demonstrated that the phenomenological model had a better agreement than the empirical model, with mean relative errors of 31.81% and 10.36% for pressure drop and liquid holdup, respectively.
Article
Engineering, Environmental
Nemanja Vucetic, Pasi Virtanen, Andrey Shchukarev, Tapio Salmi, Jyri-Pekka Mikkola
Summary: This study provides a step forward in understanding the Mizoroki-Heck reaction, specifically when iodobenzene and butyl acrylate react using a Pd Supported Ionic Liquid Catalyst (SILCA) in a continuous packed bed reactor. The catalyst leaching was minimized and a simple continuous flow process was proposed, achieving high catalytic activity and productivity.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Qian Fu, Feng Xin, Xiaohong Yin, Yuexiao Song, Yongsheng Xu
Summary: The liquid phase catalytic exchange of hydrogen isotopes using Pt/modified carbon nitride catalysts shows excellent catalytic performance and stability compared to Pt/activated carbon catalysts, making it a promising process for upgrading recycle water in nuclear power stations.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Energy & Fuels
Diego Trevisan Melfi, Marcelo Kaminski Lenzi, Luiz Pereira Ramos, Marcos Lucio Corazza
Summary: The study demonstrates that the esterification of levulinic acid with ethanol assisted by supercritical carbon dioxide (scCO(2)) and catalyzed by Amberlyst-15 can achieve near-equilibrium levulinic acid conversions in a relatively short time. The use of the Peng-Robinson equation and a v-T flash algorithm for the two-phase system allowed for successful modeling of the reaction with scCO(2) in heterogeneous catalytic systems.
Article
Green & Sustainable Science & Technology
Bowen Wang, Meng Ni, Shiye Zhang, Zhi Liu, Shangfeng Jiang, Longhai Zhang, Feikun Zhou, Kui Jiao
Summary: A two-phase analytical PEME model incorporating the liquid saturation jump effect was developed in this study, and intelligent parameter estimation using a genetic algorithm was proposed for model validation. The results proved the effectiveness of the proposed intelligent parameter estimation using in-house experiments and experimental results from previous studies. Simulation results showed that increasing the ACL porosity, decreasing permeability and thickness of the ACL can increase the limiting current density within the investigated range. Additionally, increasing the cathode pressure and membrane permeability benefits water management inside the PEME and increases the limiting current density.
Review
Energy & Fuels
Naoki Mimura
Summary: Gold catalysts were used for the oxidation reaction of glycerol, resulting in high value-added carboxylic acids. Catalysts suitable for flow reactors with both high activity and long life have been developed. Investigation of the reaction mechanism and the state of other noble metals in the catalysts has provided insights into the reaction mechanism and its influencing factors.
JOURNAL OF THE JAPAN PETROLEUM INSTITUTE
(2023)
Article
Energy & Fuels
Lucas Pinto Bernar, Caio Campos Ferreira, Augusto Fernando de Freitas Costa, Haroldo Jorge da Silva Ribeiro, Wenderson Gomes dos Santos, Lia Martins Pereira, Anderson Mathias Pereira, Nathalia Lobato Moraes, Fernanda Paula da Costa Assuncao, Silvio Alex Pereira da Mota, Douglas Alberto Rocha de Castro, Marcelo Costa Santos, Neyson Martins Mendonca, Sergio Duvoisin, Luiz Eduardo Pizarro Borges, Nelio Teixeira Machado
Summary: This study investigated the influence of reaction time and catalyst-to-residual fat ratio on the yields, physicochemical properties, and chemical composition of bio-oils during catalytic upgrading of residual fat. The results showed that increasing the catalyst-to-tallow ratio decreased the bio-oil yields. GC-MS analysis identified hydrocarbons and oxygenates as the main compounds in the liquid reaction products. The selectivity of hydrocarbons increased with reaction time, while the selectivity of oxygenates decreased.
Article
Chemistry, Physical
S. Humbert, E. Devers, C. Lesage, C. Legens, L. Lemaitre, L. Sorbier, F. De Geuser, V. Briois
Summary: Increasing the molybdenum content in sulfide catalysts can improve their activity, with the distribution of MoS2 particles playing a crucial role. Anomalous Small-Angle X-ray Scattering (ASAXS) has been used to analyze the microstructural organization of the molybdenum active phase, revealing the impact of additives and sulfidation conditions on catalytic performance. The study demonstrates the potential of ASAXS in providing detailed insights on the multi-scale organization of the active phase.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Applied
Qingyuan Zheng, Jack H. Williams, Scott Elgersma, Mick D. Mantle, Andrew J. Sederman, G. Leendert Bezemer, Constant M. Guedon, Lynn F. Gladden
Summary: In this study, a pilot-scale fixed-bed reactor compatible with NMR/MRI was developed for Fischer-Tropsch synthesis. Multiple magnetic resonance techniques were applied to quantitatively characterize different product species within catalyst pellets, providing valuable information for catalyst and reactor optimization.
Article
Chemistry, Applied
Lisa Ramisch, Sebastian Pfaff, Sabrina M. Gericke, Edvin Lundgren, Johan Zetterberg
Summary: We present a combination of optical operando techniques that allow simultaneous measurement of adsorbed species on catalyst surfaces, monitoring of surface oxide formation, and imaging of the gas phase above the catalyst surface. The experimental setup was validated by studying CO oxidation on Pd(100) at different pressures, revealing the effects of pressure on the heterogeneous catalytic reaction.
Article
Chemistry, Applied
Marta Paniagua, Gabriel Morales, Juan A. Melero, Daniel Garcia-Salgado
Summary: The influence of common impurities in levulinic acid on the catalytic performance of different acid catalysts for bio-jet fuel production was studied. It was found that furfural had the greatest detrimental effect on catalyst performance, while propyl-sulfonic acid-modified SBA-15 and sulfonic acid resin Amberlyst-70 showed good regeneration ability.
Article
Chemistry, Applied
Jesus Tapiador, Pedro Leo, Guillermo Calleja, Gisela Orcajo
Summary: This study presents a new MOF material, Zn-URJC-13, with acid and basic sites, permanent porosity, and high affinity to CO2 molecules. The Zn-URJC-13 catalyst exhibits efficient performance in CO2 cycloaddition reactions and can be reused multiple times.
Article
Chemistry, Applied
Dan Zhao, Vita A. Kondratenko, Dmitry E. Doronkin, Shanlei Han, Jan-Dierk Grunwaldt, Uwe Rodemerck, David Linke, Evgenii V. Kondratenko
Summary: This study demonstrates the potential of cheap and commercially available Zr or Ti-based supports and ZnO to serve as active and selective catalysts for propane dehydrogenation (PDH). The catalytically active species formed in situ under PDH conditions consist of isolated ZnOx. ZnOx on the surface of LaZrOx shows the highest rate of propene formation.
Article
Chemistry, Applied
Hanbyeol Kim, Jung Rae Kim, Young-Kwon Park, Jeong-Myeong Ha, Jungho Jae
Summary: In this study, metal phosphates were used as catalysts for biomass conversion to produce sustainable aromatics through DielsAlder cycloaddition reactions. The effects of synthesis method, activation method, and P/Ti molar ratio on the structure and acid properties of titanium phosphate catalysts were systematically studied. The mesoporous titanium phosphate catalyst synthesized by hydrothermal method at 180℃ for 12 h followed by ethanol refluxing at 60℃ for 24 h at a molar P/Ti ratio of 1 showed the highest surface area and acid site density.
Article
Chemistry, Applied
Yasin Khani, Sumin Pyo, Kwang-Eun Jeong, Chul-Ung Kim, Moonis Ali Khan, Byong-Hun Jeon, Kun-Yi Andrew Lin, Siyoung Q. Choi, Young-Kwon Park
Summary: A protonated form of Zeolite Socony Mobil-5 (H-ZSM-5) catalyst was synthesized through a hydrothermal method using different sources of silica. The effect of loading the catalyst with yttrium, samarium, and gadolinium on the acidic properties was investigated. Among the metal-loaded catalysts, the Sm/LHZ catalyst showed the best performance in the methanol to propylene conversion due to its high amount of weak and intermediate acid sites, while the Gd-LHZ catalyst increased the selectivity towards ethane and propane.
Article
Chemistry, Applied
Michael Franc, Ivana Cisarova, Jan Vesely
Summary: The present study investigates an enantioselective cyclization of enals with imidazolone derivatives catalyzed by a combination of achiral Pd(0) complex and chiral secondary amine. Corresponding spirocyclic imidazolones were produced in high yields with moderate diastereoselectivity and excellent enantioselectivity. The developed co-operative catalytic methodology provides a highly substituted spirocyclic scaffold with four stereogenic centers under mild conditions.
Article
Chemistry, Applied
Mauro Alvarez, Jennifer Cueto, David P. Serrano, Pablo Marin, Salvador Ordonez
Summary: This study focuses on improving the formulation and preparation methods of catalysts for the production of dimethyl carbonate. By using suitable catalyst preparation methods and copper salt precursors, the researchers successfully produced catalysts with optimal performance for dimethyl carbonate formation.
Article
Chemistry, Applied
Claudia J. Keijzer, Luc C. J. Smulders, Dennie Wezendonk, Jan Willem de Rijk, Petra E. de Jongh
Summary: This study investigates the catalytic behavior of alpha-alumina supported silver catalysts in the presence of chloride. It is found that the particle size of silver can affect the selectivity of the catalyst, but different strategies lead to different results. In this size range, the selectivity of ethylene oxide is correlated to the Ag : Al2O3 surface ratio.
Article
Chemistry, Applied
Takeshi Aihara, Wataru Aoki, Michikazu Hara, Keigo Kamata
Summary: The development of acid-base bifunctional catalysts is important for promoting specific chemical transformations. In this study, Ti-based perovskite oxides were synthesized and used as catalysts for two C-C bond-forming reactions (cyanosilylation and Knoevenagel condensation). The highly pure SrTiO3 nanoparticles with a high specific surface area exhibited the highest catalytic performance, and could be easily recovered and reused.
Article
Chemistry, Applied
Olga Gorlova, Petra Pribylova, Eliska Vyskocilova, Katerina Peroutkova, Jan Kohout, Iva Paterova
Summary: This study investigates the Baeyer-Villiger oxidation of beta-cyclocitral using tin-modified mixed oxides as catalysts. The optimal reaction conditions and the effects of various factors on the reaction course and selectivity were determined. The results show that tin-modified mixed oxides exhibit high activity and selectivity in the oxidation reaction.
Article
Chemistry, Applied
M. I. Avila, M. M. Alonso-Doncel, L. Briones, G. Gomez-Pozuelo, J. M. Escola, D. P. Serrano, A. Peral, J. A. Botas
Summary: The catalytic fast pyrolysis of lignin using ion-exchanged zeolite catalysts showed significant improvements in bio-oil quality and the production of aromatic hydrocarbons and oxygenated compounds.
Article
Chemistry, Applied
Enrico Catizzone, Giorgia Ferrarelli, Paolo Bruno, Girolamo Giordano, Massimo Migliori
Summary: The acid-catalysed alcohol conversion reaction is a promising route for de-fossilization strategies. Research on pure alcohol conversion and simultaneous dehydration of mixed alcohols have shown different product compositions, with the type and distribution of acid sites affecting the reaction mechanism.
Article
Chemistry, Applied
Alireza Ranjbari, Juho Kim, Jihee Yu, Jiyun Kim, Mireu Park, Nayoung Kim, Kristof Demeestere, Philippe M. Heynderickx
Summary: This study investigated a novel kinetic model for the adsorption and photocatalytic degradation of methyl orange using commercial ZnO and reduced ZnO photocatalysts. The results provided new insights into the interaction of catalysts with molecules of different charges and compared with a previous study on methylene blue. The presence of oxygen vacancies in ZnO and their effects on adsorption and photocatalytic degradation were analyzed, and the photocatalytic degradation rate of reduced ZnO was found to increase significantly.