Article
Energy & Fuels
Richuan Rao, Hanwen Liang, Chunming Hu, Huaze Dong, Xiongzi Dong, Yongqiang Tang, Song Fang, Qiang Ling
Summary: Ag-CeO2 catalysts were synthesized using different methods to study their catalytic performance in CO combustion. The surface chemical state of Ag and CeO2 nanoparticles significantly influenced the interaction at the Ag-CeO2 interface. Urea-assisted pyrolysis resulted in an interface with more metallic Ag species, improving the reductivity of CeO2 and enhancing the catalyst performance. Activated carbon-assisted pyrolysis led to an interface with more positively charged Ag+ ions, requiring higher CO conversion temperature. The addition of sodium salts promoted the transformation of the Ag-CeO2 interface, resulting in more Ce3+ cations and enhanced catalyst performance.
Article
Chemistry, Inorganic & Nuclear
Guanlun Guo, Jing Yu, Mingrui Wei
Summary: In this study, an Ag-CeO2-LSCF composite catalyst was prepared by impregnation method. The change in catalytic soot performance of the LSCF catalyst before and after composite was investigated. The results showed that the A-C-L composite catalyst exhibited a good microstructure and had lower characteristic temperatures compared to pure LSCF. The catalytic performance of the A-C-L composite catalyst was found to be the best when the Ag content was 8 wt%.
INORGANIC CHEMISTRY COMMUNICATIONS
(2022)
Article
Chemistry, Applied
A. Serve, A. Boreave, B. Cartoixa, K. Pajot, P. Vernoux
Summary: This study investigates the catalytic activity of Ag nanoparticles dispersed on various supports with different redox properties for soot combustion. The results show that the catalytic performance is related to the Ag surface concentration, and different contact modes have different impacts on catalytic performances. Moreover, the catalysts show remarkable hydrothermal stability after ageing.
Article
Engineering, Chemical
Yunrong Zhao, Aijing Ma, Gangguo Zhao, Jianshen Wang, Shaopu Hu, Dan Liu, Alex T. Kuvarega, Bhekie B. Mamba, Jianzhou Gui
Summary: In this study, a uniform acanthosphere-like CeO2 catalyst endowed with porous spikes was designed and prepared, showing outstanding catalytic performance and high thermal stability.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Article
Thermodynamics
Jia Fang, Chengcheng Yi, Ping Pu, Chen Chen, Yi Yang, Jiaxin Wang, Bin Lin
Summary: Ag/CeO2 catalyst synthesized by hydrothermal method was studied under different catalyst content, ash, and Ag load. It was found that Ag loading enhanced the catalytic activity of CeO2 and reduced the peak combustion temperature of soot. The catalytic effect of Ag/CeO2 was influenced by catalyst content, Ag load, and ash.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Engineering, Chemical
Siyu Gao, Di Yu, Shengran Zhou, Chunlei Zhang, Lanyi Wang, Xiaoqiang Fan, Xuehua Yu, Zhen Zhao
Summary: With the increasing strictness of environmental protection regulations, reducing pollution from diesel vehicle exhaust has become a widespread concern. This study synthesizes MnOx/CeO2 nanosphere catalysts with high reactive oxygen species using a two-step hydrothermal method, which show good catalytic activity and prospects for practical applications.
Article
Engineering, Environmental
Jaesung Lee, Min Woo Lee, Min June Kim, Jae Hwan Lee, Eun Jun Lee, ChangHo Jung, Jin Woo Choung, Chang Hwan Kim, Kwan-Young Lee
Summary: The study compares Ag/LaCeO2 catalysts with different La contents to analyze the effect of La on catalytic performance. It is found that La doping can increase reducibility and oxygen vacancies, as well as improve soot oxidation performance, while excess La doping leads to a decrease in catalytic activity.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Environmental
Zhen Zhao, Jing Ma, Min Li, Wei Liu, Xiaodong Wu, Shuang Liu
Summary: This study investigated the reducibility and activity of three Ag/CeO2 model catalysts with different types of silver species supporting on CeO2. The results showed that silver facilitated the generation of oxygen species on CeO2 through two pathways, leading to boosted soot combustion efficiency.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Environmental Sciences
Zonglin Li, Hong Ni, Pan Wang, Zhengtao Liu, Chengcheng Ao, Lidong Zhang, Yunjing Wang
Summary: Ag/CeO2 is a promising catalyst for mobile source soot emission control technologies, but there is a trade-off between hydrothermal aging resistance and catalytic oxidation performance. Through TGA experiments and characterization, the hydrothermal aging mechanism of Ag/CeO2 catalysts was investigated and the lattice morphology and valence changes were studied. The degradation mechanism of Ag/CeO2 catalysts in vapor environment was explained based on density functional and molecular thermodynamics theories. The decreased catalytic activity of Ag/CeO2 after hydrothermal aging was attributed to the less agglomeration and decreased O-II/O-I and Ce3+/Ce4+ compared with CeO2.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Thermodynamics
Zonglin Li, Pan Wang, Chengcheng Ao, Zhongwei Meng, Lidong Zhang
Summary: Thermogravimetric analysis was conducted on CeO2 and K/CeO2 catalysts prepared with the incipient wetness impregnation method to study the soot catalytic combustion. The structure, morphology, and catalytic activity of the catalysts were investigated using various techniques. Density functional theory was used to explain the mechanism of the decrease in catalytic activity. The results showed that K doping enhanced the catalytic performance through the Mars-Van Krevelen mechanism but also caused loss of active sites due to Ostwald ripening.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Chemistry, Physical
Zihao Teng, Xiaokun Yi, Chenhang Zhang, Chi He, Yulong Yang, Qinglan Hao, Baojuan Dou, Feng Bin
Summary: CO self-sustaining catalytic combustion is a potential means to efficiently convert off-gases from steelmaking. Designing model catalysts is crucial for understanding the reaction process and optimizing catalysts, with Cu2O exposing (1 0 0), (1 1 1), and (1 1 0) planes being excellent materials. In this study, morphological CeO2/Cu2O inverse model catalysts were synthesized to investigate the synergistic effect and reaction mechanism. The results showed that the ignition temperature is lowered on the interface due to the synergistic effect, while the combustion after ignition is controlled by Cu2O planes providing lattice oxygen for CO reaction. Additionally, the exposure of different planes plays a significant role in the reaction process, with O-termination on (1 0 0) inhibiting the interaction, Cu-termination on (1 1 0) surface structure, and coordinately unsaturated Cu+ on open (1 1 1) surface contributing to superior catalytic performance.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Hao Zhang, Xiaohui Gao, Binwei Gong, Shijie Shao, Chensheng Tu, Jun Pan, Yangyang Wang, Qiguang Dai, Yanglong Guo, Xingyi Wang
Summary: MoOx/CeO2 catalysts with different forms of MoOx on CeO2 were prepared for the catalytic oxidation of 1,2-dichloroethane. The acidity and surface oxygen from CeO2 domain play important roles in the activity of the catalysts.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Jae Hwan Lee, Min June Kim, Eun Jun Lee, Dae-Won Lee, Chang Hwan Kim, Kwan-Young Lee
Summary: The study reveals that modifying the Rh loading can enhance the catalytic properties of CeO2, with the optimal Rh(2)Ce catalyst exhibiting higher reducibility and active oxygen species adsorption capacity. The promotional effect of Rh on the Ag/CeO2 catalyst results in higher catalytic activity, and the interaction between Rh and Ag induces changes in electronic states.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Jingjing Tan, Jing He, Kuan Gao, Shanhui Zhu, Jinglei Cui, Long Huang, Yulei Zhu, Yongxiang Zhao
Summary: This study investigates the hydrogenation of furfural to furfuryl alcohol using different morphologies of Cu/CeO2 catalyst. The results show that the Cu/CeO2-R (110) catalyst exhibits superior catalytic performance, with a high yield of 98%. The structure-activity relationship reveals that the catalyst's intrinsic activity is positively correlated with the concentration of oxygen vacancies and Cu(0) metal sites. DFT calculations and in-situ FTIR further confirm that the Cu/CeO2-R (110) catalyst with more oxygen vacancies promotes the adsorption and activation of furfural on its surface.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Xinying Wen, Wuchao Li, Jiaxing Yan, Xiaojiao Wang, Enbo Ren, Zhuofan Shi, Jun Li, Xuegang Ding, Shengpeng Mo, Deqing Mo
Summary: This study investigates the promoting effect of strong metal-support interactions (SMSIs) on the catalytic oxidation of ethyl acetate using Pd/CeO2 catalysts with different CeO2 support morphologies. The results show that the catalytic activity of Pd/CeO2 catalysts is closely related to their structure, and the SMSIs between Pd nanoparticles and CeO2 support play a crucial role in the catalytic reaction.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
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.