Article
Green & Sustainable Science & Technology
Jiajin Huang, JiaYu Chen, Jinze Yao, Siyao Zhao, Xingbei Wu, Qibin Xia
Summary: The challenge in SCR of NOx with NH3 is to improve de-NOx activity at low temperatures and increase tolerance towards SO2 poisoning. In this study, V and Ce oxides were loaded on deactivated SCR catalysts via impregnation to recover de-NOx activity. The resulting V-Ce@CAT catalyst showed high NOx conversions of 85-95% over a wide temperature range, and also exhibited improved reactivity after introducing SO2.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Chemistry, Applied
Ruiyang Chen, Sha Peng, Yao Wang, Xiaoying Qi, Zhiming Liu
Summary: An environmentally friendly Ce@W core-shell catalyst was developed for the selective catalytic reduction of NOx. It has higher tolerance to SO2 and H2O and displays 100% conversion of NOx and selectivity to N2 in the temperature range of 250-450°C. The enhanced performance is attributed to the strong interactions between CeO2 (100) and WO3, which increase the presence of Ce3+ and surface chemisorbed oxygen.
JOURNAL OF RARE EARTHS
(2023)
Article
Engineering, Environmental
Wei Chen, Shan Yang, Hao Liu, Fang Huang, Qinghao Shao, Lichen Liu, Jingfang Sun, Chuanzhi Sun, Dezhan Chen, Lin Dong
Summary: A single-atom Ce-modified a-Fe2O3 catalyst with 7% atomic percentage of Ce was synthesized using a citric acid-assisted sol-gel method. The catalyst showed excellent performance for the selective catalytic reduction of NOx with NH3 over a wide operating temperature range and exhibited good resistance to high temperature, humidity, and SO2. The atomic dispersion of Ce species is critical for the formation of Fe-O-Ce sites in the catalyst.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Applied
Chaopeng Duan, Ruitang Guo, Yuanzhen Liu, Guilin Wu, Yufang Miao, Jingwen Gu, Weiguo Pan
Summary: The study found that the addition of Holmium (Ho) on CeTi catalyst can significantly enhance its tolerance to alkali metal K in exhaust gas. The main reason for the improvement of K resistance is the enhanced surface acidity and redox capability, higher concentration of Ce3+ species, and surface chemisorbed oxygen.
JOURNAL OF RARE EARTHS
(2022)
Article
Chemistry, Multidisciplinary
Wenjie Liu, Yifei Long, Shinian Liu, Yongyan Zhou, Xin Tong, Yajie Yin, Xiaoyi Li, Kang Hu, Jiangjun Hu
Summary: In this study, Cu and Ce were added to commercial V-W-Ti catalysts to enhance the activities of NH3 oxidation and NH3-SCR. The addition of Ce reduced the detrimental effects of H2O and SO2 and increased the surface active oxygen. Furthermore, loaded Ce and Cu improved the surface acidity and redox property of SCR catalysts.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2022)
Review
Chemistry, Applied
Dong Wook Kwon, Somin Lee, Jongsik Kim, Kwan-Young Lee, Heon Phil Ha
Summary: The roles of WO3 and SiO2 as supported on TiO2 in Ce-V catalysts were systematically investigated for NH3-SCR and NH3-oxidation at high temperatures. The addition of SiO2 and WO3 to TiO2 resulted in increased surface area, reduced nanoparticle size, and enhanced catalytic defects and oxygen species on Ce-V/TWS surface. Increasing (V4+ + V3+) fraction improved catalytic activity, with WO3 and SiO2 promoting redox properties and making Ce-V/TWS the most suitable catalyst for N-2 production via NH3 direct oxidation at high temperatures.
Article
Chemistry, Applied
Yiqing Zeng, Shule Zhang
Summary: The roles of amorphous and crystalline structures on CePO4 catalyst during the selective catalytic reduction (SCR) of NOx by NH3 were investigated. The findings indicate that the amorphous CePO4 species show higher activity at low temperature, while the crystalline CePO4 species exhibit high activity only at high temperature.
JOURNAL OF RARE EARTHS
(2022)
Article
Engineering, Chemical
Xueke Shi, Jiaxiu Guo, Ting Shen, Aidong Fan, Yongjun Liu, Shandong Yuan
Summary: Ce-modified La-Mn perovskite catalysts exhibit enhanced catalytic performance for NOx removal, achieving high conversion rates at relatively low temperatures and maintaining stability in the presence of sulfur dioxide and water. Ce doping improves the catalyst's tolerance to SO2 and enhances its specific surface area, acidic sites, chemically adsorbed oxygen, and redox performance.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2021)
Article
Chemistry, Physical
Daobing Shu, Tianhu Chen, Haibo Liu, Heng Xie, Xuehua Zou, Ping Zhang, Can Wang, Zhengyan Han, Dong Chen
Summary: This study synthesized a series of novel and superior xFe-Ce-V catalysts and systematically investigated their performance in ammonia-selective catalytic reduction of nitrogen oxides (NH3-SCR) for the first time. Introducing Ce significantly improved the catalyst's activity, selectivity, and resistance to water and SO2, with 0.75Fe-Ce-V exhibiting the best de-NOx performance. The introduction of Ce increased the surface adsorbed oxygen, BET surface area, and acidity, while promoting the formation of intermediate species, thereby enhancing the catalyst's activity. Both the Eley-Rideal and Langmuir-Hinshelwood mechanisms were involved in the NO reduction reaction, with Ce enhancing the contribution of the latter.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Dongdong Ren, Keting Gui, Shaochen Gu
Summary: The study reveals that Ce doping can effectively decrease the activation energy of the decomposition of ammonium sulfate and promote its decomposition on the catalyst surface, while Mn doping hardly improves the decomposition of ammonium sulfate on the catalyst surface. Therefore, doping Ce on the gamma-Fe2O3 catalyst can effectively improve the sulfur resistance of the catalyst, while Mn has little effect.
APPLIED SURFACE SCIENCE
(2021)
Article
Engineering, Chemical
Hao Shu, Yuling Liu, Yang Jia, Chuanchuan Dou, Feng Bai
Summary: In this study, halogen-modified Cu-Ce-BTC catalysts were synthesized and their synergistic denitration and mercury removal performance were investigated. The results showed that Cl had the highest catalytic activity among the halogens, achieving high removal rates of NO and Hg-0 at 240°C. However, NO had a minor inhibitory effect on NH3 removal and SO2 and H2O had inhibitory effects on NO and Hg-0 removal.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Engineering, Environmental
Yuhan Zhou, Buxin Su, Shan Ren, Zhichao Chen, Zenghui Su, Jie Yang, Lin Chen, Mingming Wang
Summary: This study found that doping Nb2O5 can enhance the SCR performance and sulfur resistance of Zn-Mn-Ce/AC catalyst, form new acidic sites by preferentially reacting with SO2, promote NH3 adsorption and inhibit SO2 adsorption, which hinders the reaction between NH3 and SO2 and slows the formation of ammonium sulfate channels on the catalyst.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Materials Science, Multidisciplinary
Junqiang Xu, Xianlin Zou, Guorong Chen, Yanrong Zhang, Qiang Zhang, Fang Guo
Summary: A series of vanadium-based catalysts with different doping amounts of cerium and nickel were studied for NH3-SCR, with results showing that doping of nickel or cerium can enhance catalytic activity and widen the temperature window, and the co-modification catalyst possesses higher redox ability.
Article
Materials Science, Multidisciplinary
Tao Zhou, Jiang Jin, Hua Zhang
Summary: Mn-Ce catalysts modified by Mo were loaded on low-density porous ceramics (LDPC) for simultaneous denitrification and dust removal. The Mn-Ce-Mo catalyst on LDPC had nearly 99% NOx conversion efficiency from 120 degrees C to 200 degrees C and still maintained more than 90% NOx conversion efficiency when the filtration velocity reached to 4 m/min. Mn-Ce-Mo catalysts/LDPC not only exhibited excellent catalytic performance at low temperature, they also exhibited good resistance to H2O and SO2.
Article
Chemistry, Applied
Shuang Liu, Pan Yao, Qingjin Lin, Shuhao Xu, Mingming Pei, Jianli Wang, Haidi Xu, Yaoqiang Chen
Summary: WO3 and MoO3 are often used as acidic promoters to improve the NH3-SCR performance of composite oxide catalysts, but recent research showed significant differences in their effects on CeZrOx, with WO3/CeZrOx exhibiting wider operating temperature window and higher NOx removal efficiency compared to MoO3/CeZrOx.
Article
Chemistry, Applied
Qingyun Wang, Meiqing Shen, Jianqiang Wang, Chen Wang, Jun Wang
Summary: By one-pot synthesis of Ce/SAPO-34, the inclusion of Ce enhances the low-temperature hydrothermal stability of the material, maintaining structural and acidic stability. Ce3? at exchange sites on the surface effectively prevents structural collapse.
JOURNAL OF RARE EARTHS
(2021)
Article
Engineering, Environmental
Chen Wang, Jun Wang, Jianqiang Wang, Meiqing Shen
Summary: The introduction of potassium ions into Cu/SAPO-34 catalysts via ion exchange improves their stability during low-temperature hydrothermal aging. The catalysts with potassium loading exhibit improved structure, acidity, and active site conservation after hydrothermal aging. A combined system of Fe/Beta and potassium-loaded Cu/SAPO-34 catalysts shows potential for NO(x) elimination in real-world applications.
FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING
(2021)
Article
Chemistry, Physical
Guanghao Cheng, Gurong Shen, Jun Wang, Yunhao Wang, Weibo Zhang, Jianqiang Wang, Meiqing Shen
Summary: The study found that theta-Al2O3 is more conducive to stabilizing Rh compared to gamma-Al2O3, reducing the amount of occluded Rh. During hydrothermal aging, non-interacting Rh transforms into strongly-interacting Rh and occluded Rh. Non-interacting and strongly-interacting Rh may exist in the forms of Rh/Rh3+ and Rh4+.
Article
Chemistry, Physical
Zexiang Chen, Mingdong Wang, Jun Wang, Chen Wang, Jianqiang Wang, Wei Li, Meiqing Shen
Summary: The crystal size significantly affects the NOx adsorption and desorption on Pd/SSZ-13, with smaller SSZ-13 zeolites showing better NOx storage capacity and Pd dispersion for easier Pdn+ ion diffusion. This finding can help guide the design of advanced zeolite supported PNAs.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Construction & Building Technology
Huifen Liu, Kezeng Li, Jianqiang Wang, Chunxiang Cheng
Summary: By combining field monitoring and finite element numerical simulation, the stress and deformation characteristics of deep foundation pits during excavation and support construction were analyzed. Suggestions for monitoring and construction were provided for similar engineering projects.
ADVANCES IN CIVIL ENGINEERING
(2021)
Article
Thermodynamics
Nan Meng, Tailu Li, Jianqiang Wang, Xiangfei Kong, Yanan Jia, Qinghua Liu, Haosen Qin
Summary: A novel supercritical CO2 cycle with CO2 pressurization process is proposed to improve generation performance and reduce power consumption. The optimization rates under the best operating conditions for the proposed supercritical CO2 cycle and CO2 pressurization process are 19.8% and 4.3%, respectively.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Chemistry, Physical
Jingxin Sang, Tan Zheng, Liu Xu, Xin Zhou, Shijian Tian, Jiatong Sun, Xiaofeng Xu, Jianqiang Wang, Shuguang Zhao, Yang Liu
Summary: This study discusses the effects of surface topology change on metal-insulator transition behaviors of VO2/Al2O3 thin films prepared by DC sputtering. It is found that grain size and lattice strain play significant roles in improving the metal-insulator transition, with increasing crystalline size enhancing sheet conductivity and lattice strain modulating T-MIT.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Green & Sustainable Science & Technology
Tailu Li, Haosen Qin, Jianqiang Wang, Xiang Gao, Nan Meng, Yanan Jia, Qinghua Liu
Summary: The present study introduces a novel energy system combining various energy sources, with a unique coupling relationship between three turbine units on clear days, showing satisfactory thermodynamic properties.
Article
Chemistry, Physical
Zexiang Chen, Meiqing Shen, Chen Wang, Jianqiang Wang, Jun Wang, Gurong Shen
Summary: By controlling the crystal size of Cu/SSZ-13, its resistance to alkali metals can be improved, making it more resistant to sodium poisoning. Larger crystal sizes of Cu/SSZ-13 distribute Cu more evenly in the crystal core, making it less likely to be replaced by Na to generate CuO, effectively controlling the side reaction of NH3 oxidation and the generation of N2O.
Article
Chemistry, Applied
Bo Wang, Jianqiang Wang, Xiaobing Zhang
Summary: The study applied the Moving Particle Semi-implicit Method to investigate the thermal field on solid propellant grain with cracks, verifying its application in heat conduction. By comparing and analyzing the thermal field distribution and heat transfer efficiency under different crack properties, conclusions were drawn.
PROPELLANTS EXPLOSIVES PYROTECHNICS
(2022)
Editorial Material
Ergonomics
Jaeyoung Lee, Helai Huang, Jianqiang Wang, Mohammed Quddus
Summary: This special issue gathers 36 papers from researchers around the world, exploring the impact of Intelligent Connected Vehicles (ICVs) on traffic safety. The research reveals challenges and future directions in the field of ICVs.
ACCIDENT ANALYSIS AND PREVENTION
(2022)
Article
Thermodynamics
Jianqiang Wang
Summary: The present study uses Smoothed Particle Hydrodynamics to analyze the melting process inside a multi-tube horizontal container. The Lagrangian method simplifies the moving boundary and phase change calculations, while the enthalpy method and Boussinesq assumption are used to solve the melting and natural convection problems. The results show that natural convection enhances the overall thermal performance, and a higher Rayleigh number increases the melting speed and energy storage. The melting rate is faster in the upper region due to buoyancy force. The thermal performance is more sensitive to distance rather than the angle between inner tubes in the multi-tube configuration, with a larger distance leading to weakened stratification and shorter melting time.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Bo Wang, Fei Wang, Xiaobing Zhang, Jianqiang Wang, Tao Xue
Summary: This study numerically simulates the heat transfer process and gas flow in a converging-diverging cooling structure. The converging-diverging holes show better film cooling effectiveness compared to the traditional cylindrical film holes. The maximum aperture, inclination angle, and blowing ratio of the holes have significant influences on the separation motion, film cooling effectiveness, and vortex structure.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Chemistry, Physical
Yi Zhu, Jun Wang, Yanping Zhai, Gurong Shen, Jianqiang Wang, Chen Wang, Meiqing Shen
Summary: Using Pd/beta as a passive NOx adsorber effectively reduces cold-start NOx emissions from automotive diesel engines. This study explores the prevention of Pd ion reduction and finds that Pd ions anchored near T1-T2 sites remain stable, while those near T3-T9 sites can be easily reduced. Preserved Pd ions correspond to stable NOx storage capability and the appropriate desorption temperature.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Chao Liu, Jun Wang, Zexiang Chen, Jianqiang Wang, Meiqing Shen
Summary: This study investigated the chemistry of NOx adsorption and desorption in the presence of C3H6, showing that the addition of C3H6 can enhance the NOx adsorption capacity and increase the NOx desorption temperature of PNAs. Spectroscopic and computational investigations revealed that the formation of more Pd+ in the presence of C3H6 contributed to higher NOx storage capacity. Furthermore, the shielding effect of Pd-NC3H6O on Pd+-NO improved the NOx desorption temperature.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)