Article
Chemistry, Physical
Jae-Rang Youn, Min-Jae Kim, Seung-Jae Lee, In-Soo Ryu, Hyung Chul Yoon, Soon Kwan Jeong, Kyubock Lee, Sang Goo Jeon
Summary: By adding CNTs to Mn-Ce/TiO2 catalyst, the efficiency and N-2 selectivity of low-temperature selective catalytic reduction of NO with NH3 can be significantly improved. The addition of CNTs provides more NOx adsorption sites, making the reaction more efficient.
CATALYSIS COMMUNICATIONS
(2021)
Article
Engineering, Environmental
Yi Wei, Peiyuan Liang, Yunhe Li, Yingping Zhao, Xiubo Min, Ping Tao, Jiangliang Hu, Tianjun Sun
Summary: A series of Mn-Fe mixed oxides doped with CeO2, Al2O3, and Sm2O3 were prepared and used as catalysts for NH3-SCR of marine diesel exhausts. The co-doped Mn-Fe oxide catalyst showed the best deNOx activity and SO2 tolerance. The addition of Ce promoted the formation of Mn-Fe solid solutions, while Al enhanced the dispersion of different elements in the catalysts. The introduction of Ce, Al, and Sm species adjusted the reduction properties, increased surface acidity sites, and improved catalytic activity.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Engineering, Environmental
Lin Chen, Shan Ren, Lian Liu, Buxin Su, Jie Yang, Zhichao Chen, Mingming Wang, Qingcai Liu
Summary: The Mn-Ce/zeolite catalysts were synthesized to study their NH3-SCR performance at low temperatures. The Mn-Ce/X catalyst showed the highest NO conversion and SO2 resistance, while Mn-Ce/ZSM-5 and Mn-Ce/Beta catalysts had high NO conversion at higher temperatures. Furthermore, Mn-Ce/X catalyst had better acid sites and stability, promoting NH3-SCR activity.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Multidisciplinary Sciences
Lieven E. Gevers, Linga R. Enakonda, Ameen Shahid, Samy Ould-Chikh, Cristina I. Q. Silva, Pasi P. Paalanen, Antonio Aguilar-Tapia, Jean-Louis Hazemann, Mohamed Nejib Hedhili, Fei Wen, Javier Ruiz-Martinez
Summary: There is an ongoing debate about the role of Ce in Mn-based catalysts for selective catalytic reduction of NOx at low temperature. This study demonstrates that Ce has a structural promoting effect but negatively affects the intrinsic catalytic activity of Mn.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Wei Zhang, Kang Xie, Yunhao Tang, Shan Cheng, Mengxia Qing, Yanni Xuan, Chuan Qin, Mengyao Dong, Yunhe Zhou, Jie Li
Summary: Perovskites with flexible structures and excellent redox properties are promising catalysts for denitration reactions. In this study, the effect of Ce and Cu substitution on the physicochemical properties of perovskite catalysts in an NH3-SCR system was investigated. The results showed that Ce substitution improved the denitration activity of LaMnO3 catalysts, while Cu substitution further enhanced the denitration activity. The higher denitration activity of La0.9Ce0.1MnO3 was primarily attributed to its larger surface area, which facilitated the adsorption of NH3 and NO. On the other hand, the improved denitration activity of La0.9Ce0.1Mn0.8Cu0.2O3 was due to the development of Cu active sites and Ce3+ content, which promoted redox reactions on the catalyst surface. The findings highlight the importance of appropriate cerium and copper substitution in enhancing the denitration activity of La-Mn perovskite catalysts.
Article
Materials Science, Multidisciplinary
Jisai Chen, Mutao Xu, Qijie Jin, Xiaohuan Zhi, Yingwen Chen, Xue Li, Yao Lu, Yan Wang, Haitao Xu
Summary: This study investigated the promotion mechanism of SnO2 modification on catalyst performance. The results showed that the Sn-Mn-Ce-Co-O-x catalyst exhibited the best activity when the SnO2 content was 8%. The SnO2 modification mainly contributed to the generation of Mn4+, increased chemisorbed oxygen on the catalyst surface, and improved the redox performance. Additionally, various intermediate products were generated in the catalytic reaction, covering the catalytic sites.
JOURNAL OF MATERIALS RESEARCH
(2022)
Article
Chemistry, Physical
Liyan Wang, Bin Wang, Yangyang Guo, Yang Zheng, Tingyu Zhu
Summary: The interaction between CO oxidation and NH3-SCR reaction has been studied over α-MnO2-Cu nanorod catalyst. The addition of Cu species enhances the catalytic performance and CO and NH3 have effects on CO oxidation and NO reduction.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
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
Chemistry, Physical
Javier Ruiz-Martinez, Lieven E. Gevers, Linga R. Enakonda, Ameen Shahid, Fei Wen
Summary: This study investigates the poisoning effect of SO2 on binary MnTi and ternary MnCeTi mixed oxides for the NH3-SCR reaction. The addition of Ce widens the optimal operational temperature range, but the presence of SO2 drastically decreases catalytic activity in all catalyst samples. Further characterization reveals adsorption and poisoning of SO2 on the catalysts, and doping studies do not provide effective solutions to suppress SO2 deactivation.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Energy & Fuels
Mingming Wang, Shan Ren, Yanhua Jiang, Buxin Su, Zhichao Chen, Weizao Liu, Jie Yang, Lin Chen
Summary: By co-doping Sm and Fe into the Mn-Ce/AC catalyst, the resistance to Pb poisoning was enhanced, leading to improved low-temperature NH3-SCR performance.
Article
Engineering, Environmental
Yang Geng, Wenpo Shan, Fudong Liu, Shijian Yang
Summary: The introduction of tungsten as a promoter enhanced the catalytic activity of Mn-Ce oxide catalyst for NH3-SCR, increasing the NOx conversion above 150 degrees C while decreasing N2O production. Doped tungsten inhibited charge imbalance and reducibility, leading to higher NOx conversion above 150 degrees C over Mn3CeW0.3Ox compared to Mn3CeOx. Kinetic study showed that nu(SCR) over Mn(3)CeW(0.3)O(x) was higher than over Mn3CeOx, consistent with the SCR activity.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Engineering, Environmental
Xuelian Li, Yongfang Niu, Jing Li, Min Yang, Rujie Chen, Dan Shao, Xinmei Zheng, Chuanwei Zhang, Yanxing Qi
Summary: This study synthesized trace amounts of Co-doped Ce-Mn-based metal oxide catalysts and investigated their catalytic performance, moisture and sulfur resistance, and regeneration ability. The results showed that the Co-doped catalyst exhibited excellent activity in denitrification and catalytic combustion, as well as high sulfur resistance. Furthermore, the mechanism of the catalyst's high sulfur resistance was studied in detail.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Zheng Gong, Bangda Wang, Wenhua Chen, Shenggui Ma, Wenju Jiang, Xia Jiang
Summary: The study introduced a new strategy for the high value utilization of waste straw by preparing a Mn-doped carbon/mesoporous silica composite catalyst, which demonstrated high catalytic activity and redox performance for low-temperature denitration. The results showed significant improvements in NO conversion rate, surface acidity, and H-2 consumption compared to traditional activated carbon and mesoporous silica catalysts.
Article
Engineering, Environmental
Wen Nie, Xiao Yan, Fengning Yu, Qiu Bao, Na Li, Weiwei Zhou, Wenjin Niu, Qifan Tian
Summary: A series of experiments were conducted to study the effects of adding Ce and Cu to Mn/gamma-Al2O3 catalysts. The results showed that the addition of these auxiliary metals improved the catalyst's performance, reducibility, reaction mechanism, and the production of intermediate products that promote the NH3-SCR reaction.
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
(2023)
Article
Engineering, Environmental
JiaYu Chen, Peng Fu, Daofei Lv, Yang Chen, Meiling Fan, Junliang Wu, Amogh Meshram, Bin Mu, Xiang Li, Qibin Xia
Summary: The high-performance denitration catalyst based on Mn-Ce mixed-oxide demonstrated outstanding low-temperature activity and excellent SO2 tolerance, with abundant active sites and a porous structure. The introduction of SO2 enhanced catalytic activity and suppressed unwanted ammonia oxidation. The reaction pathway on the mixed oxide was confirmed to be the L-H mechanism based on in situ DRIFTS.
CHEMICAL ENGINEERING JOURNAL
(2021)
