Article
Chemistry, Applied
Paola Riani, Gabriella Garbarino, Tullio Cavattoni, Guido Busca
Summary: Two Co/SiO2 catalysts exhibit different catalytic behaviors in CO2 methanation and reverse water gas shift reactions, with carbon nanotubes produced not affecting the catalyst activity.
Article
Chemistry, Physical
J. F. Da Costa-Serra, A. Miralles-Martinez, B. Garcia-Munoz, S. Maestro-Cuadrado, A. Chica
Summary: Ni and Co catalysts supported on ITQ-6 zeolite were synthesized and evaluated for ethanol steam reforming. Co/ITQ-6 showed higher conversion and hydrogen production than Ni/ITQ-6, attributed to smaller cobalt particle size. Co/ITQ-6 also exhibited lower selectivity for by-products and higher stability. Rating: 8/10.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Concetta Ruocco, Vincenzo Palma, Gianmario Picciotti, Antonio Coppola
Summary: The study comprehensively investigates the kinetics of ethanol oxidative reforming over a Pt-Ni/CeO2-Al2O3 catalyst in the presence of fuel grade bioethanol, and develops a kinetic model that includes the formation of solid carbon. The results show a satisfactory fitting of the experimental data for the reaction scheme involving ethylene and acetaldehyde formation, their subsequent decomposition, methane oxidation, and steam reforming and water gas shift reaction. Furthermore, the catalyst exhibits high stability and near-zero carbon emission during long-term testing.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Environmental
Gabriela Grzybek, Magdalena Greluk, Piotr Patulski, Pawel Stelmachowski, Karolina Tarach, Grzegorz Slowik, Marek Rotko, Susana Valencia, Fernando Rey, Kinga Gora-Marek
Summary: The focus of the ongoing global energy transformation is on hydrogen production in the ethanol steam reforming (ESR) process. Researchers have successfully developed a cobalt catalyst based on the ZSM-5 zeolite support, and analyzed its performance using various physicochemical characterization methods and real-time UV-Vis and FT-IR spectroscopy studies in the ESR conditions. The influence of potassium introduction and the impact of zeolite acidity on the cobalt phase oxidation state were also investigated. The study results challenge the existing paradigm of low activity and stability of zeolite-based ESR catalysts, and provide hope for the development of competitive catalysts.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Esteban L. Fornero, Julia Vecchietti, Manuela Boucinha Rodrigues, Juan C. Hernandez-Garcido, Adrian L. Bonivardi
Summary: The performance of gallium promoted cobalt-ceria catalysts for ethanol steam reforming was studied. Gallium promoted catalyst showed higher conversion efficiency of ethanol and production of oxygenated by-products compared to cobalt-ceria catalyst. The role and mechanism of gallium promotion were analyzed and explained through detailed characterization and analysis of the catalyst.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Environmental
M. N. Efimov, E. Yu. Mironova, A. A. Vasilev, D. G. Muratov, N. A. Zhilyaeva, S. Zh. Ozkan, G. P. Karpacheva
Summary: A method for simultaneous formation of mono- or bimetallic nanoparticles and a highly porous carbon support was proposed. The bimetallic catalyst showed significant advantage in ethanol steam reforming, with filamentous carbon presence observed in spent cobalt-based catalysts without deactivation.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Energy & Fuels
Shanshan Shao, Pengfei Zhang, Xiaohua Li, Yongbo Yu
Summary: Hydrogen production from simulated aqueous bio-oil was studied using a two-stage system with dolomite and NiO/CeO2-Al2O3 catalyst. The increase in hydrogen yield was higher for the less active catalyst in the two-stage system. Higher reforming temperature and steam/carbon ratio improved hydrogen production and gas composition. Phenol removal was enhanced by pre-reforming with dolomite, reducing coke deposition. The deactivated catalysts showed lower coke deposition in the two-stage system compared to the one-stage system. The study improved the stability of Ni-based catalyst for hydrogen production.
Article
Chemistry, Physical
Adriano H. Braga, Daniela C. de Oliveira, Alan R. Taschin, Joao B. O. Santos, Jean Marcel R. Gallo, Jose M. C. Bueno
Summary: A spectroscopic and microscopic investigation was conducted on bimetallic nanoparticles in Co-Ni/MgAl2O4 catalysts used for steam reforming of ethanol. The study sheds light on the significant impact of Co-Ni alloy in reforming reactions, providing insights into catalytic performance.
Article
Chemistry, Physical
Surendar Moogi, Lingaiah Nakka, S. Sai Prasad Potharaju, Ashfaq Ahmed, Abid Farooq, Sang-Chul Jung, Gwang Hoon Rhee, Young-Kwon Park
Summary: Different cobalt-based mixed oxide catalysts were synthesized and tested for hydrogen production from glycerol steam reforming, with the 5Cu20CM catalyst showing the best performance attributed to its small particle size, high dispersion, and large surface area.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Magdalena Greluk, Wojciech Gac, Marek Rotko, Grzegorz Slowik, Sylwia Turczyniak-Surdacka
Summary: The addition of citric acid improved the dispersion and reduced particle size of metal particles, while catalysts prepared from ammonia solution showed the largest metal particle size. In steam reforming of ethanol, dehydrogenation of ethanol takes place preferentially on terrace sites, while cleavage of C-C bond is favored by edge/steps sites.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Vildan Aker, Nezihe Ayas
Summary: Ethanol steam reforming (ESR) is a promising technology for hydrogen production, and the study focuses on the influence of cobalt loading and ESR conditions on H2 selectivity and catalytic stability. Ni-Co/Al2O3 (5 wt% Co) catalyst exhibited the best performance with small metal crystallite size, high surface area, and high catalytic activity. Optimal conditions for 100% ethanol conversion and maximum H2 selectivity were found to be 600°C, 0.05 L/gcat.h, and S:C molar ratio of 12:1. The Ni-Co interaction was found to affect the catalytic activity, and the stability test showed minimal coke deposition.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
S. Sayas, J. F. Da Costa-Serra, A. Chica
Summary: This study introduces natural sepiolite from Spain as a promising support material for preparing cobalt catalysts with high activity and hydrogen selectivity in the steam reforming of furfural. The precipitation method was found to favor the formation of smaller metallic Co particles with high dispersion, leading to better catalytic performance and resistance to deactivation during the reaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Multidisciplinary
Bogdan Ulejczyk, Lukasz Nogal, Michal Mlotek, Krzysztof Krawczyk
Summary: Ethanol steam reforming is a potential source of green hydrogen, but the process is complex and catalyst deactivation due to coke deposition is a common problem. In this study, a plasma reactor was used to mitigate the coke-induced disturbance. The research focused on the influence of steam, and the optimal water/ethanol molar ratio was found to be 4. At this ratio, the energy efficiency reached 22.5 mol(H-2)/kWh with a high ethanol conversion of 92%.
Article
Multidisciplinary Sciences
Hao Meng, Yusen Yang, Tianyao Shen, Wei Liu, Lei Wang, Pan Yin, Zhen Ren, Yiming Niu, Bingsen Zhang, Lirong Zheng, Hong Yan, Jian Zhang, Feng-Shou Xiao, Min Wei, Xue Duan
Summary: This paper reports a RhNi/TiO2 catalyst with a tunable RhNi-TiO2 strong bimetal-support interaction derived from the structure topological transformation of RhNiTi-layered double hydroxides precursors. The resulting catalyst exhibits extraordinary catalytic performance toward ethanol steam reforming reaction with high H-2 yield, production rate, and operational stability.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Yelisbeth Escalante, Manuel F. Gomez, Mariana N. Barroso
Summary: Co-CeO2/MgAl2O4 catalysts were synthesized with different impregnation orders of Co and Ce, and their performance in the ethanol steam reforming (ESR) reaction was evaluated. The impregnation order affected the interactions between metal-metal and/or metal-support, as well as the surface molar ratio of Co0/Con+, Ce3+/Ce4+, and Co/Ce, which in turn influenced the catalytic behavior in the ESR reaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Applied
Wojciech Gac, Witold Zawadzki, Marek Rotko, Grzegorz Slowik, Magdalena Greluk
TOPICS IN CATALYSIS
(2019)
Article
Chemistry, Physical
Wojciech Gac, Witold Zawadzki, Magdalena Greluk, Grzegorz Slowik, Andrzej Machocki, Joan Papavasiliou, George Avgouropoulos
Article
Chemistry, Applied
Christos Papadopoulos, Konstantinos Kappis, Joan Papavasiliou, John Vakros, Marcin Kusmierz, Wojciech Gac, Yiannis Georgiou, Yiannis Deligiannakis, George Avgouropoulos
Review
Chemistry, Applied
Wojciech Gac, Witold Zawadzki, Marek Rotko, Magdalena Greluk, Grzegorz Slowik, Gunther Kolb
Article
Engineering, Chemical
Stefan Neuberg, Helmut Pennemann, Vetrivel Shanmugam, Raphael Thiermann, Ralf Zapf, Wojciech Gac, Magdalena Greluk, Witold Zawadzki, Gunther Kolb
CHEMICAL ENGINEERING & TECHNOLOGY
(2019)
Article
Chemistry, Physical
Tomasz Kondratowicz, Marek Drozdek, Marek Michalik, Wojciech Gac, Marta Gajewska, Piotr Kustrowski
APPLIED SURFACE SCIENCE
(2020)
Article
Chemistry, Physical
Magdalena Greluk, Wojciech Gac, Marek Rotko, Grzegorz Slowik, Sylwia Turczyniak-Surdacka
Summary: The addition of citric acid improved the dispersion and reduced particle size of metal particles, while catalysts prepared from ammonia solution showed the largest metal particle size. In steam reforming of ethanol, dehydrogenation of ethanol takes place preferentially on terrace sites, while cleavage of C-C bond is favored by edge/steps sites.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Wojciech Gac, Witold Zawadzki, Marek Rotko, Magdalena Greluk, Grzegorz Slowik, Helmut Pennemann, Stefan Neuberg, Ralf Zapf, Gunther Kolb
Summary: The study reported direct methanation of CO2 over ceria- and alumina-supported nickel catalysts in the feed stream containing methane and traces of H2S. The results showed that ceria-supported nickel catalyst exhibited higher conversion at 350 degrees Celsius, while the introduction of trace amounts of H2S led to rapid decrease in CO2 conversion and CH4 selectivity.
Article
Chemistry, Physical
Wojciech Gac, Witold Zawadzki, Grzegorz Slowik, Marcin Kusmierz, Stanislaw Dzwigaj
Summary: Two model nickel catalysts for CO2 methanation, NiHAlBEA and NiSiBEA, were prepared using unmodified and dealuminated BEA-type zeolite supports. NiSiBEA showed higher CO2 conversion and methane selectivity at low reaction temperatures, as well as improved resistance to sintering at high reaction temperatures. The dispersion of nickel and sintering resistance in NiSiBEA led to the delay of catalyst deactivation by H2S.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Wojciech Gac, Witold Zawadzki, Magdalena Greluk, Grzegorz Slowik, Marek Rotko, Marcin Kusmierz
Summary: The influence of Ce and W promoters on alumina-supported nickel catalysts in the CO2 methanation reaction has been investigated. The introduction of Ce promoter increases the active surface area and CO2 conversion, while the addition of a small amount of W promoter enhances the activity but decreases the active surface area of the catalyst.
Proceedings Paper
Physics, Atomic, Molecular & Chemical
K. Winiarczyk, W. Gac, M. Goral-Kowalczyk, Z. Surowiec
Summary: The magnetic properties of magnetite nanoparticles depend on their chemical and physical parameters, which can be controlled through a synthesis process. In this study, magnetite nanoparticles were synthesized with surface modification using DMSA, and their structure and magnetic properties were characterized. FTIR and Mossbauer spectroscopy were used to study the role of DMSA and temperature-induced changes in the magnetic properties, showing complex spectra for magnetic suspensions due to long-range interactions.
HYPERFINE INTERACTIONS
(2021)
Article
Chemistry, Physical
Christos Papadopoulos, Konstantinos Kappis, Joan Papavasiliou, John Vakros, Aspasia Antonelou, Wojciech Gac, Haibin Li, George Avgouropoulos
Summary: CuCe mixed oxides are commonly used for preferential CO oxidation in the purification of hydrogen-rich gas stream. This study investigated the synthesis of various ceria supports and the preparation of CuCe mixed-oxide catalysts. It found that modifying the hydrothermal parameters can tune the properties of the supports, leading to highly active and selective catalysts. The nature of the reduced copper species and the optimum content in oxygen vacancies play crucial roles in the catalytic performance.
Article
Thermodynamics
A. Derylo-Marczewska, D. Sternik, A. Swiatkowski, K. Kusmierek, W. Gac, B. Buczek
Summary: The study investigated the adsorption of phenol on activated carbon with different surface chemistry from water and cyclohexane solutions. It was found that oxygen surface groups and solvent type played a significant role in phenol adsorption, with oxidized carbon showing decreased adsorption in water compared to organic solvent. Thermal analysis revealed that the adsorption process of phenol on carbons is mainly physical in nature.
THERMOCHIMICA ACTA
(2022)
Article
Engineering, Environmental
Konstantinos Kappis, Joan Papavasiliou, Marcin Kusmierz, Grzegorz Slowikc, Yifan Li, Haibin Li, Wojciech Gac, George Avgouropoulos
Summary: Steam reforming of methanol using CuZnOx catalysts was investigated, and the incorporation of Ga was found to improve catalyst performance by altering the environment and promoting the formation of ZnGa2O4 spinels and oxygen vacancies. The presence of Ga2O3 (15 wt%) was beneficial for activity and selectivity, and the formation of a CuZnGaAlOx system further enhanced the performance. The most active material showed promising results in an integrated internal reforming methanol fuel cell operating at 220 degrees C.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Wojciech Gac, Witold Zawadzki, Marcin Kusmierz, Grzegorz Slowik, Wojciech Grudzinski
Summary: Two series of catalysts containing different amounts of neodymium were prepared by the impregnation method, using nano-CeO2 and gamma-Al2O3 as supports. Ceria supported nickel catalysts showed high activity in CO2 methanation reaction and weak activity changes were observed with an increase in Nd content. Complex changes in the nature of their redox and base centres were indicated by various characterizations.
APPLIED SURFACE SCIENCE
(2023)
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.
