Article
Chemistry, Applied
Qiang He, Jinfa Chen, Limei Gan, Menglan Gao, Miaomiao Zan, Yanfei Xiao
Summary: Clay minerals play a crucial role in ion adsorption type rare earth ore, controlling the adsorption and desorption processes of rare earth. Experimental studies reveal that the adsorption and competitive adsorption abilities of cations depend on their charge and hydrolysis properties, while the desorption of rare earth and aluminum is influenced by the concentration driving forces of high concentrations of magnesium and ammonium ions, although high-concentration desorbents may hinder the desorption reactions. Additionally, the solid-phase Al(OH)(3) generated at high peak aluminum concentration delays the efflux of aluminum, partially separating rare earth from aluminum.
JOURNAL OF RARE EARTHS
(2023)
Article
Materials Science, Multidisciplinary
Jiancai Ding, Rui Ran, Jingbo Jia, Duan Weng, Zhigang Yang
Summary: La-deficient La1-xCexMnO3 mixed oxides obtained by selective dissolution in nitric acid exhibited increased specific surface areas, better reducibility, and greater activity. Incorporation of Ce stabilized the structure and maintained long-term activity, with La0.95Ce0.05MnO3 showing comparable catalytic activity to 1% Pd/Al2O3 catalysts even in the presence of CO2 and H2O.
PROGRESS IN NATURAL SCIENCE-MATERIALS INTERNATIONAL
(2021)
Article
Chemistry, Applied
Qingwen Wang, Wenyong Deng, Xinchen Lin, Xigen Huang, Ling Wei, Lei Gong, Changxiang Liu, Guangbin Liu, Qian Liu
Summary: Mesoporous Ce-Mn-Co ternary metal oxide fabricated via an efficient oxalate-precursor-based soft reactive grinding route showed excellent activity in advanced oxidation of methylene blue in water, attributed to the synergistic effect of Ce, Mn, and Co promoting the formation of more lattice defects, higher specific surface area, and smaller particle size.
JOURNAL OF RARE EARTHS
(2021)
Review
Chemistry, Physical
Chang Liu, Longhua Xu, Jiushuai Deng, Jia Tian, Donghui Wang, Kai Xue, Xi Zhang, Yan Wang, Jinmei Fang, Jiongtian Liu
Summary: Rare earth elements are indispensable and valuable for scientific and technological advancements in the 21st century, making the extraction of high-quality rare earth resources a global priority. Bastnasite-(Ce) is a significant rare earth mineral, and research efforts have focused on separating it from gangue minerals using the flotation process, with flotation reagents playing a critical role. This paper provides a detailed summary of current research on the behavior of bastnasite-(Ce) flotation agents on minerals and their interaction with mineral surfaces during flotation separation, and outlines future prospects for further research.
ADVANCES IN COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Analytical
Lina Qiu, Jiandi Li, Weiwei Zhang, Aijun Gong, Xiaotao Yuan, Yang Liu
Summary: The study investigated the extraction and back-extraction effects of TODGA on various rare earth elements, achieving optimal experimental conditions by adjusting parameters. The results showed that TODGA had good separation effects on La(III), Ce(III), Pr(III), Nd(III), and mixed rare earths.
Article
Engineering, Environmental
Amrita Das, K. R. S. Chandrakumar, Bhaskar Paul, Jagannath Gupta, Nidhi Gupta, Ajoy K. Singh, Vivekanand Kain
Summary: Separation of hard actinides from rare earth metal ions is a challenging task that requires selecting suitable ligands. In this study, two oxygen donating ligands were synthesized and tested for their ability to separate hard actinides and rare earths. The binding of metal ions with the adsorbents was found to be controlled by the anions present in the aqueous medium.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Applied
Lihua Huang, Jian Hua
Summary: In this study, Ce-Mn/TiO2 catalyst was doped with Ho and Sm to enhance its denitration performance at low temperature. Ho doping increased the amount of acid sites and improved low temperature redox property, leading to excellent DeNOx performance. Sm doping resulted in a decline in redox property but increased the acid sites of Ce-Mn/TiO2. Both Ho and Sm doping improved sulfur resistance by inhibiting the adsorption of SO2 and formation of sulfate. Ho-modified Ce-Mn/TiO2 showed better sulfur resistance due to its higher number of surface acid sites.
JOURNAL OF RARE EARTHS
(2023)
Article
Chemistry, Applied
Lei Li, Liping Song, Zhaoyang Fei, Wei Chu, Xiaofeng Luo, Jinlong Yan
Summary: The effects of different support materials on the catalytic performance of toluene removal were investigated. The Mn-Ce binary oxides supported on ZrO2 showed the best catalytic activity, attributed to low-temperature reducibility and abundant surface species. XPS and TPR results revealed good interaction between Mn and Ce elements in MnCe/ZrO2, and weak interaction between metal oxide and support promoted the dispersion and reduction of MnCe oxides at low temperature.
JOURNAL OF RARE EARTHS
(2022)
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
Chemistry, Applied
Shuqi Zhao, Kunli Song, Ruiyu Jiang, Dandan Ma, Hongming Long, Jian- Wen Shi
Summary: For the first time, a modified Mn-Ce composite oxide catalyst (Sm-MnCe) supported on cordierite was prepared and evaluated for its denitration performance in the NH3-SCR reaction. The results showed that the 0.1Sm-MnCe/CC catalyst exhibited the highest de-NOx efficiency with over 80% NOx conversion in the temperature range of 60 to 270 degrees C. Moreover, the catalyst showed good stability in the presence of 100 ppm SO2, maintaining high NOx conversion for 15 hours. This study provides insights for the development of monolithic catalysts for low-temperature SCR de-NOx technology.
Article
Energy & Fuels
Fengyuan Liu, Junqi Li, Hong Yong Sohn, Chaoyi Chen, Jian Yang, Xudong Liu, Yuanpei Lan, Wei Zhang, Qin Wang, Li Liu
Summary: The aim of this study was to investigate the interactions on Mn-Ce interface and their influence on low temperature selective catalytic reduction (SCR) for NOx removal. Three Mn-Ce catalysts with similar particle size and morphology but different Mn-Ce interface areas were prepared. MnO2@CeO2-F showed the tightest and largest amount of Mn-Ce interfaces, exhibiting the highest NO conversion degree, strongest activity of Mn species, and lowest generation of N2O. The results provided strong evidence for the importance of Mn/Ce redox and clarified the effects of Mn-Ce redox on low-temperature SCR process.
Article
Metallurgy & Metallurgical Engineering
Wang Yi-nan, Zhao Xu-teng, Zheng Zu-wei, Jiang Han, Chen Ting, Zhang Yi-ran, Cao Hong-lin, Lin He, Zhan Reggie
Summary: This study aimed to develop a passive NOx absorber using a series of transition metal catalysts loaded on TiO2 with Pd as a promoter. The Mn-containing catalysts showed excellent NOx adsorption ability and appropriate desorption temperature, while Ce- and Cu-containing samples were not suitable. The loading of Pd reduced the valence states of transition metals and surface oxygen percentage. The types of adsorbed substances were not influenced by Pd in Mn, Ce, and Cu series, but the storage forms of NOx were significantly different on Pd-Fe-Ti and Fe-Ti.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2022)
Article
Engineering, Environmental
Lei Jiang, Danyang Li, Guixian Deng, Chunqiang Lu, Linan Huang, Zhiqiang Li, Haiwen Xu, Xing Zhu, Hua Wang, Kongzhai Li
Summary: The surface reconstruction and lattice distortion of La1-xCexCoO3-δ catalysts were induced by acid-etching, leading to the exsolution of small Ce and Co oxides and the embedding of Ce species in the crystal lattice. These changes improved the catalytic activity and stability of the catalysts, making them resistant to impurities poisoning.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Chen Wan, Dan Zhou, Bing Xue
Summary: Currently, there is a significant lack of knowledge in the research of rare earth exploitation, particularly in terms of carbon emission coefficient. This study utilizes the life cycle assessment approach to compute the carbon footprint of producing mixed oxide rare earths using ionic rare earth resources and analyze the sources and influencing factors of this carbon footprint. The findings indicate that the carbon footprint of producing 1 kg of mixed oxide rare earths using ionic rare earths ranges from 17.8 to 24.3 kg CO2 eq with an uncertainty of 15.54%. The total carbon footprint from 2012 to 2017 reaches 1.6 x 10(8) to 2.19 x 10(8) kg CO2 eq/year, and decreases to 1.51 x 10(8) to 2.07 x 10(8) kg CO2 eq/year after 2018. The carbon footprint of illegal mining is approximately 1.50 x 10(8) to 1.59 x 10(8) kg CO2 eq/year. Generally, a higher recovery rate leads to a lower carbon footprint of 1 kg REO production, but the benefit of carbon footprint reduction diminishes as the recovery rate increases. Finally, the new generation of magnesium salt leaching technology, while mitigating ammonia nitrogen pollution in ionic rare earth mines, will increase the carbon footprint of the product.
Article
Chemistry, Applied
Yi Zhu, Quan Wang, Li Lan, Shanhu Chen, Jingjing Zhang
Summary: Constructing bimetallic catalysts of cerium and manganese with excellent catalytic performance for soot combustion is currently a research frontier. Experimental results show that the catalytic activity increases first and then decreases with the increase of manganese content within a certain range. The key factors for catalytic activity are the easily reducible and highly dispersed surface manganese oxide species, as well as the contact performance of the external surface, when the adsorbed surface oxygen, lattice oxygen, specific surface area, and total reduction amount of the catalysts reach a certain value.
JOURNAL OF RARE EARTHS
(2022)
Article
Chemistry, Physical
Yuanyuan Zhang, Zhichun Si, Jian Gao, Yuxiang Liu, Liping Liu, Xiaodong Wu, Rui Ran, Duan Weng
APPLIED SURFACE SCIENCE
(2019)
Article
Environmental Sciences
Yue Ma, Xiaodong Wu, Junyu Zhang, Rui Ran, Zhichun Si, Duan Weng
JOURNAL OF ENVIRONMENTAL SCIENCES
(2019)
Article
Chemistry, Physical
Ping Liu, Yimeng Xing, Yuxiang Liu, Zhichun Si, Lin Xie, Duan Weng, Feiyu Kang
APPLIED SURFACE SCIENCE
(2020)
Article
Engineering, Environmental
Liping Liu, Xiaodong Wu, Yue Ma, Xu Zhang, Rui Ran, Zhichun Si, Duan Weng
CHEMICAL ENGINEERING JOURNAL
(2020)
Article
Chemistry, Physical
Qi Song, Rui Ran, Jiancai Ding, Xiaodong Wu, Zichun Si, Duan Weng
MOLECULAR CATALYSIS
(2020)
Article
Chemistry, Physical
Liping Liu, Xiaodong Wu, Yue Ma, Rui Ran, Zhichun Si, Duan Weng
CATALYSIS SURVEYS FROM ASIA
(2020)
Article
Environmental Sciences
Shuting Luo, Xiaodong Wu, Baofang Jin, Shuang Liu, Rui Ran, Zhichun Si, Duan Weng
JOURNAL OF ENVIRONMENTAL SCIENCES
(2020)
Article
Materials Science, Multidisciplinary
Yibin Liu, Yue Ma, Duan Weng, Xiaodong Wu, Zhichun Si
PROGRESS IN NATURAL SCIENCE-MATERIALS INTERNATIONAL
(2020)
Article
Chemistry, Physical
Baofang Jin, Baohuai Zhao, Shuang Liu, Zhenguo Li, Kaixiang Li, Rui Ran, Zhichun Si, Duan Weng, Xiaodong Wu
APPLIED CATALYSIS B-ENVIRONMENTAL
(2020)
Article
Nanoscience & Nanotechnology
Yishui Liu, Mengxi Pei, Huanhuan Liang, Xiaodong Wu, Bo Li, Zhichun Si, Feiyu Kang
Summary: Volatile organic compounds (VOCs) are receiving increased attention due to their impact on air pollution and human health. Researchers have developed a photocatalytic system using few-layer CoAl-LDH as a support for Pt nanoparticles, which are coated on CeO2 nanoparticles. This system forms type II heterojunctions and improves the efficiency of VOC removal. The study provides a useful method for the preparation of high-efficiency photothermal catalysts.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Yue Ma, Yang Gao, Xiaodong Wu, Baofang Jin, Rui Ran, Zhichun Si, Duan Weng
Summary: The influences of gaseous, weakly adsorbed, and strongly adsorbed NH3 on the low-temperature hydrothermal stability of SAPO-34 and Cu-SAPO-34 were investigated in this study. The results showed that gaseous NH3 and weakly adsorbed NH3 led to catalyst deactivation, while strongly adsorbed NH4+ helped protect the catalyst's activity.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Yue Ma, Xiaodong Wu, Jiancai Ding, Liping Liu, Baofang Jin, Eric D. Walter, Rui Ran, Zhichun Si, Feng Gao, Duan Weng
Summary: A quasi-operando NH3 temperature-programmed reduction method (NH3-TPR) has been developed to quantify total Cu(ii) ions in Cu-SSZ-13 quenched from SCR-relevant reactions, and its accuracy has been confirmed by in situ EPR. The different reducibility of [Cu(OH)](+)-Z and Cu2+-2Z in SCR can be further distinguished by NH3 reduction temperatures.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Ang Li, Yuxiang Liu, Xueiun Xu, Yuanyuan Zhang, Zhichun Si, Xiaodong Wu, Rui Ran, Duan Weng
Article
Chemistry, Multidisciplinary
Liping Liu, Xi Wu, Li Wang, Xuejun Xu, Lin Gan, Zhichun Si, Jia Li, Qun Zhang, Yuxiang Liu, Yanyan Zhao, Rui Ran, Xiaodong Wu, Duan Weng, Feiyu Kang
COMMUNICATIONS CHEMISTRY
(2019)
