Article
Metallurgy & Metallurgical Engineering
Aiman Shahbaz, Muhammad Zahid
Summary: In this study, a novel and sustainable beneficiation-metallurgy process for rare earth ore extraction was proposed, which involved roasting the ore to deactivate fluorine, followed by hydrochloric acid and multistage water leaching. Under optimized conditions, high extraction rates of cerium and lanthanum were achieved, resulting in a high purity rare earth oxide product.
CANADIAN METALLURGICAL QUARTERLY
(2023)
Article
Engineering, Chemical
Chenhao Liu, Hepeng Zhang, Bing Luo, Liqing Li, Xiaoqi Sun
Summary: The extraction-precipitation method using N-lauroyl sarcosine as the precipitant shows a specific precipitation ability for rare earth, and a new enrichment process for bastnaesite leachate is developed to effectively remove impurities and reduce energy consumption and carbon emission.
MINERALS ENGINEERING
(2022)
Article
Chemistry, Physical
Gibin George, Jacob Hayes, Candyce N. Collins, Jason E. Davis, Lei Yu, Yulin Lin, Jianguo Wen, Daryush Ila, Zhiping Luo
Summary: This study investigates the photoluminescence and cathodoluminescence characteristics of rare-earth-doped CaF2 nanoparticles and their composite monoliths with epoxy. The results show that the luminescence intensity increases as the particle size decreases for single-doped particles, but decreases for codoped particles. Additionally, Eu2+- and Tb3+-codoped CaF2 nanoparticles exhibit red emission.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Chemical
Peng Cen, Xue Bian, Wenyuan Wu, Baokuan Li
Summary: The current metallurgical process for bastnaesite concentrates needs to be updated for cleaner and more efficient production. A novel beneficiation-metallurgy combination process is proposed, which can significantly reduce chemical reagent usage and energy consumption, while also inhibiting fluorine waste generation. Recovery rates for rare earths, fluorine, and calcium are high under optimum conditions, indicating economic benefits and sustainability.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Green & Sustainable Science & Technology
Peng Xing, Huiquan Li, Chunlin Ye, Liqin Zhong
Summary: The separation of rare earth elements (REEs) from rare earth molten salt slag has been a challenge due to the high fluorine content. This study presents a clean process for recycling REEs from the slag using fluorine fixation roasting and hydrometallurgical leaching. The leaching efficiencies of REEs were above 97% under optimal conditions.
JOURNAL OF SUSTAINABLE METALLURGY
(2022)
Article
Engineering, Environmental
Zhihe Cao, Baozhong Ma, Jiashun Zhou, Yongqiang Chen, Chengyan Wang
Summary: Recently, an increasing number of companies have invested in the hydrometallurgical process of laterite ores. Meanwhile, the research on disposal of laterite residue has gained attention for environmental protection, economic efficiency, and resource utilization. In this study, a reduction roasting process in the presence of CaF2 is proposed to efficiently treat laterite residue and recover valuable components. Thermodynamic calculations were conducted to understand the mechanism of phase transformation and roasting in the presence of CaF2. The results show that CaF2 reacts with certain minerals in the laterite residue to release iron and chromium, and its addition promotes the reduction, migration, aggregation, and growth of metallic iron and chromium. Optimal conditions for the addition of CaF2 and temperature were determined. The addition of 10% CaF2 resulted in a recovery rate of 95.61% for chromium and an increase in the metallization reduction of iron from 77.2% to 91.87%. The role of CaF2 was further investigated through the microstructure evolution of the roasting products.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Engineering, Environmental
Shaowei You, Shaotao Cao, Chunyang Mo, Yi Zhang, Jianwen Lu
Summary: This study presents a new process for recovering high purity calcium fluoride from wastewater. A column reactor system with calcium sulfate dihydrate as reaction medium was used, resulting in the successful production of calcium fluoride with purity exceeding 99% and reducing fluoride concentration in wastewater to less than 10 mg/L. The process effectively removes fluoride while recovering high-purity calcium fluoride and various parameters such as initial fluoride concentration, flow rate, pH, and time significantly influence fluoride removal efficiency. The study offers an effective strategy for resource utilization and standard discharge of fluorine-containing wastewater.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Yilong Li, Dan Zou, Ji Chen, Yuefeng Deng, Deqian Li
Summary: This research investigates a new method for extracting fluorine and cerium from a boric-acid-added bastnaesite sulfuric leaching liquor by Cyannex923. The effects of H3BO3 on bastnaesite leaching, extraction, and stripping process were systematically studied, along with the mechanism and conditions in each step. The findings demonstrate that the formation of B-F complex improves the extraction of Ce and F, and provides a new method for their separation and stepwise recovery.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Engineering, Chemical
Hailan Li, Jie Zhang, Ruiyong Mao, Fei Xie, Lufeng Wang, Jiangguo Cheng
Summary: The simultaneous recovery of lanthanum, cerium, and niobium from sedimentary rare earth ores (SREO) using a sulfation roasting-leaching process (SRLP) was performed. Response surface methodology (RSM) was utilized to optimize the process parameters, resulting in good recovery efficiency under the optimized conditions.
MINERALS ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Alex Norgren, Corby Anderson
Summary: This study evaluates the use of UF Falcon in gravity separation of ultra-fine bastnaesite, achieving high REO recovery rates and effective removal of calcium. Multiple stages of UF Falcon gravity separation were able to significantly increase REO content and demonstrate potential for treating a wider range of mineral materials.
Article
Engineering, Environmental
Chao Liu, Wei Luo, Zehai Liu, Jie Long, Subei Xu, Hongwei Liu, Xuegang Wang
Summary: Efficient extraction of rare earth elements from spent phosphor was achieved using microwave alkali fusion-leaching. The dielectric properties were studied, and the addition of alkali enhanced the microwave heating ability of the phosphor, resulting in improved leaching efficiency of rare earth elements. Microwave roasting showed advantages of lower temperature, shorter time, and higher leaching ratio compared to conventional roasting.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Engineering, Chemical
Ahmad Nawab, Xinbo Yang, Rick Honaker
Summary: This study introduces a new method for recovering rare earth elements (REEs), especially heavy rare earth elements (HREEs), from coal at lower acid concentrations. Different treatment methods, including roasting and direct acid baking, were investigated and compared. The results showed that direct acid baking at a lower temperature provided the best recovery of both light rare earth elements (LREEs) and HREEs. Roasting followed by acid baking also achieved high recovery rates. The improved recovery was attributed to the dehydroxylation of clay minerals and subsequent release of REE-bearing minerals.
MINERALS ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Yan Zhou, Shizhe Song, Jianxing Liu, Gongjin Cheng, He Yang, Xiangxin Xue
Summary: The study found that adding MgO during magnetizing roasting can effectively improve the decomposition rate of rare earth minerals, with a decomposition rate of 98.09% achieved at 750 degrees Celsius with a MgO dosage of 10 wt.%. The phase composition of roasted samples was characterized using XRD and SEM-EDS, and incomplete decomposition rate was investigated through observation of leaching residual with SEM-EDS. The decomposition kinetics of rare earth minerals with MgO addition was analyzed using the Ginstling-Brundshtein model, showing that the reaction rate was controlled by chemical reaction.
Article
Green & Sustainable Science & Technology
Jing Zhao, Bo Li, Xiaolin Wei
Summary: The paper introduces a dry exhaust gas treatment technology different from the traditional wet spraying process for rare earth roasting, successfully implemented in a roasting kiln to achieve dust removal, cooling, and acid condensation from exhaust gas while converting waste heat into steam. Compared to wet spraying, the dry process offers advantages including operational simplicity, small footprint, low energy consumption, low maintenance cost, and no wastewater production.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Materials Science, Multidisciplinary
Shuhao Yang, Andre Anderko, Richard E. Riman, Alexandra Navrotsky
Summary: Sodium rare earth fluorides play crucial roles in light emission and biomedical applications. Research shows that their heats of formation are related to the ionic radius of rare earth ions, and this trend is different from most rare earth oxide compounds, possibly due to changes in the coordination number of rare earth cations.
Article
Materials Science, Multidisciplinary
Peng Cen, Wenyuan Wu, Xue Bian
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2017)
Article
Materials Science, Multidisciplinary
Peng Cen, Wenyuan Wu, Xue Bian
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2018)
Article
Chemistry, Applied
Peng Cen, Xue Bian, Wenyuan Wu
JOURNAL OF RARE EARTHS
(2020)
Article
Engineering, Chemical
Peng Cen, Xue Bian, Wenyuan Wu, Baokuan Li
Summary: The current metallurgical process for bastnaesite concentrates needs to be updated for cleaner and more efficient production. A novel beneficiation-metallurgy combination process is proposed, which can significantly reduce chemical reagent usage and energy consumption, while also inhibiting fluorine waste generation. Recovery rates for rare earths, fluorine, and calcium are high under optimum conditions, indicating economic benefits and sustainability.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Review
Chemistry, Physical
Ming Cai, Xue Bian, Feng Xie, Wenyuan Wu, Peng Cen
Summary: This review article focuses on the development of cerium-based catalysts for NH3-SCR technology, including the components, preparation methods, catalytic performance, and reaction mechanisms of these catalysts. The review highlights the modification effects of various metal elements, various synthesis methods, and the physicochemical properties of the catalysts, particularly in relation to catalytic performances in the presence of SO2 and H2O. The aim is to provide technical guidance and insights for the application of NH3-SCR in NOx control.
Review
Engineering, Chemical
Peng Cen, Xue Bian, Zhannian Liu, Manyi Gu, Wenyuan Wu, Baokuan Li
Summary: Rare earth elements play an indispensable role in modern high technology, making the efficient exploitation and utilization of rare earth resources crucial. Current industrial processes are chemical and energy intensive, leading to negative impacts on the environment, thus further improvement towards cleaner production is necessary.
MINERALS ENGINEERING
(2021)
Article
Chemistry, Physical
Peng Cen, Kastriot Spahiu, Mikhail S. Tyumentsev, Mark R. St J. Foreman
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2020)
