Article
Chemistry, Multidisciplinary
Valery Muravev, Jerome F. M. Simons, Alexander Parastaev, Marcel A. Verheijen, Job J. C. Struijs, Nikolay Kosinov, Emiel J. M. Hensen
Summary: This study unveiled the rich structural dynamics of a conventional catalyst during CO oxidation, confirming the presence of different active intermediates at different temperatures. The results highlight the importance of establishing structure-activity relationships for technical catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Sungha Hwang, Yongwoo Kim, Jaeha Lee, Eunwon Lee, Hyokyoung Lee, Changho Jeong, Chang Hwan Kim, Do Heui Kim
Summary: This study reveals that CO can enhance the NOx adsorption ability of Pd/CeO2 catalyst at low temperatures. A mechanism is proposed based on the changing CO oxidation ability with increased NOx adsorption over Pd/CeO2.
Article
Chemistry, Physical
Mingzhi Wang, Peijie Ma, Zhuangzhuang Wu, Shasha Chu, Yanping Zheng, Zhaohui Zhou, Weizheng Weng
Summary: The determination of dynamic changes in supported Pd catalysts during the CO/Hydrocarbons oxidation reactions is crucial for the development of efficient catalysts for vehicle exhaust purification. This study found that Pd/CeO2 catalysts, prepared by modulating the interaction between Pd precursors and CeO2 support, exhibited different dynamic properties under CO oxidation conditions, and also showed different deactivation behaviors in the presence of C3H6. The chemical states of Pd species on CeO2 during CO oxidation were found to correlate with their redox properties, which significantly influenced the role of C3H6 and H2O in the reactions.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Yanbo Deng, Shijie Liu, Lian Fu, Yi Yuan, Anmin Zhao, Dajun Wang, Heng Zheng, Like Ouyang, Shaojun Yuan
Summary: The efficiency of CO oxidation catalysts can be improved under wet conditions by controlling the metal-support interaction of Pd/Pr-CeO2 catalysts.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
[Anonymous]
Summary: The dynamic behavior of ceria-supported Pd single atoms, clusters, and nanoparticles during CO oxidation was investigated using operando spectroscopy. The catalytic role of different Pd species was elucidated through a combination of in situ spectroscopy with transient and steady-state kinetic analysis, revealing that highly dispersed Pd-oxo species and interfacial Pd sites catalyze low-temperature CO oxidation, while metallic Pd contributes to the activity at elevated temperature.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Nanoscience & Nanotechnology
Huimin Liu, Shipeng Wu, Chao Sun, Zhen Huang, Hualong Xu, Wei Shen
Summary: Support properties regulation has been an effective method for improving noble metal catalytic performance. However, synthesizing a uniform TiO2-CeO2 solid solution in Pd-based catalysts is still challenging due to the discrepancy in solubility product constant between titanium and cerium hydroxides. In this study, an in situ capture strategy was used to fabricate a uniform TiO2-CeO2 solid solution, which served as a support for an enhanced Pd-based catalyst. The resulting catalyst exhibited superior CO oxidation activity and stability, showcasing the potential of this strategy for fabricating advanced noble metal-based catalysts.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Tao Li, Mengling Dong, Jiacheng Xu, Tiantian Zhang, Yan Sun, Ning Li, Zuliang Wu, Jing Li, Erhao Gao, Jiali Zhu, Shuiliang Yao, Yong Huang
Summary: CeO2/gamma-Al2O3, Pd/CeO2, and Pd/CeO2/gamma-Al2O3 were used for catalyzing low-concentration CH4 oxidation. It was found that nano-sized Pd could significantly enhance CH4 oxidation on CeO2/gamma-Al2O3, due to the interaction between Pd and CeO2 on gamma-Al2O3, which resulted in the formation of more oxygen vacancies and surface reactive oxygen species. Furthermore, gamma-Al2O3 facilitated the formation of bicarbonate, which promoted the gasification of bicarbonate to CO2 and enhanced CH4 oxidation.
Article
Chemistry, Physical
Jawaher Mosrati, Ali M. Abdel-Mageed, Thanh Huyen Vuong, Reni Grauke, Stephan Bartling, Nils Rockstroh, Hanan Atia, Udo Armbruster, Sebastian Wohlrab, Jabor Rabeah, Angelika Brueckner
Summary: Cu single-atom catalysts supported on CeO2-TiO2 were prepared using a sol-gel method and showed high efficiency and stability in CO oxidation. Spectroscopic methods such as infrared, electron paramagnetic resonance, and X-ray photoelectron spectroscopy revealed the mechanism of action and structure-reactivity relationships.
Article
Engineering, Chemical
Saki Shigenobu, Hajime Hojo, Hisahiro Einaga
Summary: The effect of Cu addition on the catalytic properties of Pd/CeO2 catalysts for CO oxidation was investigated. It was found that Cu addition enhanced the activity of the catalyst, but excessive addition of Cu led to agglomeration of PdO and decreased CO oxidation activity.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Engineering, Chemical
Yanbo Deng, Lian Fu, Wenjia Song, Like Ouyang, Shaojun Yuan
Summary: Cerium oxide-based materials doped with valence metals can effectively increase the oxygen vacancy content and regulate the surface and interface structure of CeO2 supported metal catalysts. In this study, CeO2 nanorods doped with transition metals (Fe, Co, Mn) and Pr were prepared and used to support Pd, significantly enhancing the activity of CO catalytic oxidation. The co-doping of Pr and Fe increases the oxygen vacancy content on the catalyst surface, promotes the activation of lattice oxygen, and strengthens the interaction and electron transport ability between Pd and the support, leading to excellent catalytic performance in CO oxidation.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Kyriaki Polychronopoulou, Ayesha A. AlKhoori, Angelos M. Efstathiou, Maguy Abi Jaoude, C. M. Damaskinos, Mark A. Baker, Alia Almutawa, Dalaver H. Anjum, Michalis A. Vasiliades, Abderrezak Belabbes, Lourdes F. Vega, Abdallah Fathy Zedan, Steven J. Hinder
Summary: Eliminating CO through oxidation over highly active and cost-effective catalysts is important for industrial and environmental processes. Doped CeO2 with transition metals was tested for CO oxidation, showing that Cu-Ce-O catalyst has the highest activity. The involvement of lattice oxygen species in the reaction and the effectiveness of different heteroatoms were investigated and quantified.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Applied
Fawei Lin, Xiao Jiang, Nuttakorn Boreriboon, Chunshan Song, Zhihua Wang, Kefa Cen
Summary: Binary supports such as TiO2-CeO2 and TiO2-ZrO2 significantly enhance CH3OH formation and selectivity, with Pd-Cu/Ti0.1Zr0.9O2 exhibiting the best catalytic performance. Lowering temperature further enhances CH3OH selectivity.
Article
Engineering, Environmental
Gina Bang, Kyung-Min Kim, Seongmin Jin, Chang-Ha Lee
Summary: The presence of other gas species in practical conditions complicates sorption-based processes. This study focuses on understanding the dynamic CO2 sorption behavior of MgO-based sorbent under practical conditions. It was found that elevated pressures significantly enhance sorption performance, while temperature has no significant influence. H2O enhances CO2 sorption kinetics and initial CO2 sorption, while CO hinders them.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Environmental
Yaeun Seo, Min Woo Lee, Hyun Jae Kim, Jin Woo Choung, ChangHo Jung, Chang Hwan Kim, Kwan-Young Lee
Summary: The study showed that doping with appropriate amounts of Ag can increase the oxygen storage capacity of the catalyst and form active Pd-0 species, leading to improved catalytic activity for the oxidation of CO and C3H6.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Chemistry, Physical
Md Robayet Ahasan, Yifan Wang, Ruigang Wang
Summary: Gas adsorption-desorption processes on oxide supported metal catalysts are critical for understanding catalytic CO oxidation mechanism. This study investigates the relationship between support structure and catalytic activity of CuOx supported on SiO2 and CeO2 nanorods and nanocubes. It was found that both Cu+/Cu2+ redox pair and lattice oxygen of CeO2 from different crystal planes play important roles in CO oxidation. The CeO2 nanorods with high surface defects promote CO adsorption and oxidation, leading to high catalytic performance for CO oxidation.
MOLECULAR CATALYSIS
(2022)
Article
Chemistry, Physical
Yanfeng Xue, Junfen Li, Pengfei Wang, Xiaojing Cui, Hongyan Zheng, Yulan Niu, Mei Dong, Zhangfeng Qin, Jianguo Wang, Weibin Fan
Summary: Regulating the Al distribution in zeolite through Sn leads to a more homogeneous spatial distribution, resulting in decreased formation of aromatics and coke species, and increased propene selectivity and catalytic stability in the MTO process.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Applied
Ying Shi, Qiuming Zhou, Zhangfeng Qin, Zhiwei Wu, Weiyong Jiao, Mei Dong, Weibin Fan, Jianguo Wang
Summary: Hierarchically structured Beta zeolites with high meso-porosity were synthesized through steam treatment using organosilanes as pore-forming reagents, followed by modification with K and Pt. The Pt/K-Beta-HS catalysts exhibited excellent performance in the aromatization of n-heptane, showing longer lifetime, higher selectivity to aromatics, and larger turnover numbers compared to conventional Beta zeolites. These results demonstrate the potential of Pt/K-Beta-HS zeolites as efficient catalysts for converting n-heptane to aromatics.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Chemistry, Physical
Li Yang, Chao Fan, Li Luo, Yanyan Chen, Zhiwei Wu, Zhangfeng Qin, Mei Dong, Weibin Fan, Jianguo Wang
Summary: The study revealed that dry ball-milling is a simple and effective method to prepare Pd/SiO2 catalysts for lean methane oxidation at low temperature, with palladium acetylacetonate being an ideal precursor. The oxidation state of Pd species plays a crucial role in determining the catalytic activity, and the PdOx/SiO2-Acac catalysts exhibit higher activity in this process.
Article
Engineering, Chemical
Shujia Guo, Sen Wang, Wenyu Zhang, Han Wang, Qian Zhang, Zhangfeng Qin, Mei Dong, Jianguo Wang, Weibin Fan
Summary: This research focuses on the direct formation of light olefins from CO2 hydrogenation. Bifunctional catalysts composed of zinc-based metal oxides and H-RUB-13 zeolite were prepared, and the selectivity of C2-4 olefins reached 64.7-83.2%. ZnZrOx/H-RUB-13 showed the highest CO2 conversion due to the presence of oxygen vacancies. Interestingly, propene and butene were the dominant hydrocarbons, indicating the potential of H-RUB-13 zeolite to suppress ethene formation. However, the distribution of light olefins also depended on the overall acidity of the bifunctional catalyst, with ZnCrOx/H-RUB-13 showing higher ethene selectivity.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Chemistry, Applied
Kai Yuan, Xiangyu Jia, Sen Wang, Sheng Fan, Shipei He, Pengfei Wang, Zhangfeng Qin, Mei Dong, Weibin Fan, Jianguo Wang
Summary: Purposefully regulating the spatial distribution of acid sites in a zeolite catalyst can effectively enhance its performance in the conversion of methanol to olefins (MTO). The use of different sodium halides in the synthesis of ZSM-11 zeolites was found to influence the location and distribution of acid sites, which in turn affected the catalytic performance in MTO. The presence of Br- or I- anions in the synthesis gel led to a uniform distribution of Al species and improved catalytic stability and selectivity in MTO.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Applied
Ying Shi, Qiuming Zhou, Zhangfeng Qin, Zhiwei Wu, Weiyong Jiao, Mei Dong, Weibin Fan, Jianguo Wang
Summary: The catalytic performance of Pt/Beta-Me catalysts modified with different alkali metals in the aromatization of n-heptane was investigated. The results showed that the modification with alkali metals can enhance the Pt dispersion, suppress cracking reactions and carbonaceous deposition, and promote the dehydroaromatization of alkanes, leading to improved catalytic stability and selectivity. The extent of modification effect varied with different alkali metals, with Rb having the highest promoting effect.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Physical
Sheng Fan, Han Wang, Shipei He, Kai Yuan, Pengfei Wang, Junfen Li, Sen Wang, Zhangfeng Qin, Mei Dong, Weibin Fan, Jianguo Wang
Summary: The finding of methylcyclohexene as a crucial reaction intermediate in the conversion of methanol to light olefins (MTO) plays a vital role in understanding the MTO reaction mechanism and further research.
Article
Engineering, Chemical
Shujia Guo, Han Wang, Zhangfeng Qin, Zhikai Li, Guofu Wang, Mei Dong, Weibin Fan, Jianguo Wang
Summary: The conversion of CO and CO2 into valuable liquid fuels and chemicals through hydrogenation has attracted significant interest. This study evaluates the feasibility, limit, and suitable conditions for these reactions through thermodynamic considerations. Results show that the hydrogenation of CO/CO2 to alcohols, light olefins, and aromatics is thermodynamically viable under appropriate conditions. Although current conversion processes may be restricted by kinetic factors, it is important to ensure that the reactions are conducted under thermodynamically feasible conditions. These results help determine the suitable operation region for CO/CO2 hydrogenation and provide directions for optimizing catalysts and processes.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Chemistry, Physical
Rui Geng, Yacong Liu, Yanxia Guo, Pengfei Wang, Mei Dong, Sen Wang, Jianguo Wang, Zhangfeng Qin, Weibin Fan
Summary: This study systematically investigated the structure evolution and regeneration behavior of Zn-modified ZSM-5 catalysts in ethylene aromatization. The results showed that the generated coke species on spent catalysts can cover acid sites and block pore channels, leading to the transformation of active ZnOH+ species into inactive ZnO. After regeneration, the catalysts were fully recovered and exhibited higher aromatic selectivity.
Article
Chemistry, Physical
Qiuming Zhou, Sen Wang, Zhiwei Wu, Zhangfeng Qin, Mei Dong, Jianguo Wang, Weibin Fan
Summary: The pore structure and acidic property of ZSM-5 zeolite were controlled using an NH4HF2 and K2CO3 post-treatment method to improve its catalytic activity and stability in alkane aromatization. The Pt/KZSM-5(deAl) catalyst exhibited high conversions and aromatic selectivities for n-heptane, n-octane, and n-nonane, and showed a long catalytic lifetime. The regulation of pore structure and acidity reduced cracking reactions and enhanced the interaction between Pt and ZSM-5 zeolite.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Sen Wang, Li Zhang, Pengfei Wang, Weiyong Jiao, Zhangfeng Qin, Mei Dong, Jianguo Wang, Unni Olsbye, Weibin Fan
Summary: This study developed a composite material capable of selectively hydrogenating CO2 to produce high-value hydrocarbons, with high product selectivity and stability. Incorporation of proper amounts of Ga into ZrO2 promoted methanol formation, avoiding the limitation of aromatics generation under high H-2 pressure.
Article
Chemistry, Physical
Tingyu Liang, Jialing Chen, Sen Wang, Pengfei Wang, Zhangfeng Qin, Fang Jin, Mei Dong, Jianguo Wang, Weibin Fan
Summary: This study investigates the effects of acid density on the methanol-to-hydrocarbon (MTH) performances and deactivation behaviors of H-MCM-22 zeolites. It is found that acid density has a significant impact on MTH performances, while acid distribution has a smaller effect. Increasing acid density promotes hydrogen transfer reactions and the formation of aromatics, ethene, and alkanes. Low acid density results in coke covering acid sites inside the micropores, while high acid density leads to massive coke deposition on the external surface. The deactivation behaviors of H-MCM-22 zeolites can be divided into three stages.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Rui Geng, Yacong Liu, Jie Gao, Yanxia Guo, Mei Dong, Sen Wang, Weibin Fan, Jianguo Wang, Zhangfeng Qin
Summary: In this study, the structure, composition, and evolution manner of Zn species in different reaction stages of ethylene aromatization over Zn-Modified ZSM-5 zeolites were investigated. The results show that the Zn species undergoes reciprocal transformation during the reaction, leading to changes in its composition and catalytic performance. This study provides important insights into the catalytic activity and deactivation mechanism of Zn/ZSM-5 catalysts.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Hong Ma, Jian Liao, Zhihong Wei, Xinxin Tian, Junfen Li, Yan-Yan Chen, Sen Wang, Hao Wang, Mei Dong, Zhangfeng Qin, Jianguo Wang, Weibin Fan
Summary: A study of ethene methylation over H-ZSM-5 using a multiscale approach revealed the importance of methanol dehydration products as methyl donors, rapid formation of propene, and the essential role of a mobile methyl cation carrier in the process.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Wenyu Zhang, Sen Wang, Shujia Guo, Zhangfeng Qin, Mei Dong, Jianguo Wang, Weibin Fan
Summary: This study demonstrates that modifying zinc-zirconium oxides with lanthanum can effectively promote the formation of methanol intermediates, leading to improved catalytic performance in CO2 hydrogenation to light olefins. The addition of lanthanum induces the formation of more oxygen vacancies on the surface of the catalyst, facilitating the adsorption and activation of CO2 and the generation of methanol intermediates. Coupling with acidic zeolites allows for the rapid conversion of the methanol intermediates into light olefins. The composite catalysts exhibit high selectivity for C-2(=)-C-4(=) hydrocarbons.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
