Article
Engineering, Chemical
Yiqian Yang, Zhijian Peng, Hui Zhao, Erqiang Wang, Chunshan Li
Summary: A series of metal-modified Mo/gamma-Al2O3 catalysts were prepared and the addition of Ce was found to increase the valence state of Mo to 6+. The study systematically investigated the influence of Ce content on catalytic performance, achieving a sulfur yield of 88.27% under optimized conditions in a fixed-bed reactor.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Qi Gao, Changqing Dong, Xiaoying Hu, Junjiao Zhang, Yanjun Zhu, Haiyang Lv, Ying Zhao, Junjie Xue, Xiaoqiang Wang
Summary: A series of Ce-Fe bimetallic oxide catalysts were prepared for CO catalytic oxidation in the presence of high concentrations of SO2. The Ce0.7Fe0.3 catalyst showed excellent CO oxidation activity and resistance to SO2 poisoning, with Fe doping playing a positive role in enhancing the performance of the catalyst.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Nanoscience & Nanotechnology
Wei Yu, Jiali Yan, Zhengwei Cui, Na Yang
Summary: Ammonium carbonate-assisted mechanochemical preparation was developed for Cu-based catalysts in steam reforming of methanol. The optimized samples showed high surface area porous structure, resulting in superior catalytic activity. The ball-milled catalysts exhibited better stability and activity compared to wet-impregnated samples.
Article
Chemistry, Multidisciplinary
Chongfei Liu, Xuetao Wang, Lili Xing, Xingxing Cheng, Xingyu Zhang, Haojie Li, Mengjie Liu
Summary: Molecular sieve catalysts containing transition metals have been prepared and studied for their catalytic performance in the reduction of NO. The introduction of Zr into the Cu-Ce/SAPO-34 molecular sieve catalysts was found to decrease the denitration efficiency due to a decrease in the total acid content of the acid sites on the catalyst surface. However, the 4Cu-4Ce-4Zr/SAPO-34 catalyst exhibited high denitration efficiency at different temperature ranges. Excessive Zr loading could disrupt the catalyst structure and decrease the denitration efficiency.
APPLIED SCIENCES-BASEL
(2023)
Article
Energy & Fuels
Ederson Osorio-Restrepo, Michael Canon-Alvarado, Carlos E. Daza
Summary: The effect of Ce on Ni/Ca-Al catalysts for CO2 methanation prepared by coprecipitation was investigated. Ce promotion resulted in an increase in catalytic conversion, attributed to the decrease in the Ni(0) particle size and the enhancement of surface carbonate species formation. The catalysts showed exceptional activity at low temperatures and high stability without the formation of CO or coke, highlighting the potential of Ce-promoted Ni/Ca-Al catalysts for CO2 methanation.
Article
Energy & Fuels
Hairong Tang, Yong He, Peixi Liu, Jiaming Shao, Fawei Lin, Zhihua Wang
Summary: It was found that the Co/CoOx@carbon catalyst (Co-650N) pyrolyzed in N2 atmosphere exhibited excellent low-temperature catalytic activity and stability, with high decomposition efficiency and resistance to SO2. The mechanisms involve the combination of oxygen and N2O molecules, the transfer and storage of oxygen species in the carbon framework, and the important role of the carbon framework in regenerating active oxygen and cobalt sites.
Article
Chemistry, Physical
T. N. Afonasenko, D. Glyzdova, V. L. Yurpalov, V. P. Konovalova, V. A. Rogov, E. Yu Gerasimov, O. A. Bulavchenko
Summary: Different oxide materials with different ratios were synthesized and characterized. It was found that MnOx-CeO2, MnOx-ZrO2-CeO2, and MnOx-ZrO2 catalysts exhibited the highest catalytic activity in the CO oxidation reaction at different calcination temperatures. The high activity was attributed to the content of easily reduced fine MnOx particles in the samples and the presence of oxygen vacancies in the form of paramagnetic defects.
Article
Materials Science, Multidisciplinary
Shuaida Zhu, Xiong Cao, Xiaoqing Cao, Yuqi Feng, Xinbing Lin, Kehua Han, Xiaoxia Li, Peng Deng
Summary: In this study, the effect of M-doped graphitic carbon nitride on the thermal decomposition of DAP-4 was investigated. Fe-g-C3N4 exhibited the best catalytic activity for the thermal decomposition of DAP-4 among the tested catalysts, significantly improving the thermal decomposition parameters. This finding may offer a new perspective for the application of DAP-4 in the field of solid rocket propellants.
MATERIALS & DESIGN
(2021)
Article
Chemistry, Physical
Wei Sun, Shijie Shao, Jun Pan, Yangyang Wang, Hangqi Xia, Xiaohui Gao, Hao Zhang, Qiguang Dai, Li Wang, Xingyi Wang
Summary: Ce-Ti-Zr mixed oxide catalysts prepared by sol-gel method exhibit high activity and stability for CH2Cl2 oxidation. The incorporation of Ce and Zr promotes the formation of hydroxyl groups, Lewis acidity and surface oxygen, leading to efficient CH2Cl2 removal.
APPLIED CATALYSIS A-GENERAL
(2022)
Article
Chemistry, Multidisciplinary
Zeyi Guo, Qi You, Lianghao Song, Guoxin Sun, Guozhu Chen, Cuncheng Li, Xianfeng Yang, Xun Hu, Xuchuan Jiang
Summary: In this study, highly dispersed ultrafine platinum particles were synthesized and anchored onto a mesoporous CeO2 structure. The presence of -NH2 groups in Ce-MOFs played a crucial role in anchoring Pt species with high dispersion, leading to the formation of Ce-Pt sites and boosting CO oxidation at low temperatures.
Article
Energy & Fuels
Pilar Tarifa, Cristina Megias-Sayago, Fernando Cazana, Miguel Gonzalez-Martin, Nieves Latorre, Eva Romeo, Juan Jose Delgado, Antonio Monzon
Summary: The study found that Ce is a better catalyst promoter than Mg, achieving higher CO2 conversion rates and CH4 selectivity over a wider temperature range. The Ni-Mg-Ce/CDC catalyst reached the highest methane yield of 80% in the temperature range of 350-400 degrees C. Ce-promoted catalysts also exhibited high activity at low temperatures.
Article
Chemistry, Physical
Weiwei Wang, Shaojia Song, Ping Wang, Miao He, Zhao Fang, Xilin Yuan, Huan Li, Chenyu Li, Xiong Wang, Yuechang Wei, Weiyu Song, Hao Xu, Zhenxing Li
Summary: The most promising approach to address the greenhouse effect and energy crisis is converting carbon dioxide into valuable liquid fuels using artificial photosynthesis. Researchers have synthesized novel g-C3N4/UiO-66(Zr/Ce) nanosheets that show excellent catalytic performance and selectivity in CO2 reduction. The close contact and chemical bonds between g-C3N4 and UiO-66(Zr/Ce) enhance electron transmission and suppress carrier quenching, while Ce doping and coordination bonds in the composite catalyst further improve CO2 reduction. The composite catalyst achieves efficient CO2 reduction to CH3OH and C2H5OH without sacrificial agents, with a higher turnover frequency compared to bulk UiO-66(Zr/Ce), and exhibits excellent stability over multiple cycles.
Article
Engineering, Chemical
Junchen Li, Cheng Zhang, Quan Li, Ting Gao, Shenghui Yu, Peng Tan, Qingyan Fang, Gang Chen
Summary: Anatase TiO2 with {001} facets (TiO2-NS) and anatase TiO2 with {101} facets (TiO2-NP) were used as carriers to prepare Mn-Ce/TiO2-NS and Mn-Ce/TiO2-NP catalysts, respectively. The Mn-Ce/TiO2-NS catalyst exhibited high specific surface area and excellent resistance to SO2, making it a promising low-temperature SCR catalyst.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Environmental
Jingjing Zou, Sarawoot Impeng, Fuli Wang, Tianwei Lan, Lulu Wang, Penglu Wang, Dengsong Zhang
Summary: This study reveals for the first time the co-poisoning effects of lead (Pb) and SO2 on catalyst activity, finding that the co-poisoning effects of Pb and SO2 differ in different catalysts and the results are unexpected. The extent of deactivation caused by Pb and SO2 co-poisoning depends on the structure of the catalyst and the properties of the active sites. This study is of great significance for the design of ceria-based SCR catalysts with resistance to heavy metals and SO2 coexistence.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Applied
Wenjie Liu, Yifei Long, Shinian Liu, Yongyan Zhou, Xin Tong, Yajie Yin, Xiaoyi Li, Kang Hu, Jiangjun Hu
Summary: In this study, V/CeeTi catalysts were modified with different transition metals using solegel and impregnation methods. The NH3 oxidation performance of the catalysts was tested for NH3-selective catalytic oxidation (NH3eSCO) and the effects of NO, SO2 and H2O were investigated. The experimental results show that the 1% CueV/CeeTi catalyst exhibits the highest ability to remove slip ammonia from coal-fired plants, with a NH3 conversion efficiency of 90% at 300 degrees C. Additionally, the CueV/CeeTi catalyst demonstrates excellent resistance to H2O and SO2. The dispersion of Cu and V on the CeeTi catalyst surface, as well as the redox cycles among Cu, V and Ce species, contribute to the enhanced oxidation capacity of the catalyst.
JOURNAL OF RARE EARTHS
(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.