Review
Engineering, Environmental
Emmanuel Yaw Owusu-Fordjour, Xinbo Yang
Summary: Bioleaching, using microorganisms to dissolve minerals and extract Rare Earth Elements (REEs) in aqueous media, has gained attention for its potential eco-friendliness compared to other extraction methods. Mixed culture bioleaching is preferred for efficient REEs extraction, promoting closed-loop recycling and reducing supply chain issues. This literature review provides an overview of challenges, opportunities, microorganisms, mechanisms, approaches, parameters, and techno-economic considerations related to REEs bioleaching, and offers recommendations for future advancements.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Biotechnology & Applied Microbiology
Michael Paper, Max Koch, Patrick Jung, Michael Lakatos, Tom Nilges, Thomas B. Brueck
Summary: This study investigated the potential of 12 cyanobacterial strains for biosorption of rare earth elements, and Nostoc sp. 20.02 showed the highest adsorption capacity. Synechococcus elongatus UTEX 2973, Calothrix brevissima SAG 34.79, Desmonostoc muscorum 90.03, and Komarekiella sp. 89.12 were also promising strains. The adsorption of metals by the strains had fast kinetics and pH value had a significant impact on the process.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2023)
Article
Engineering, Environmental
O. Pereao, K. Laatikainen, C. Bode-Aluko, O. Fatoba, E. Omoniyi, Y. Kochnev, A. N. Nechaev, P. Apel, L. Petrik
Summary: The study focuses on the preparation, characterization, and adsorption performance of PET-DGAnf nanofiber adsorbents, demonstrating their potential for rapid adsorption kinetics and high selectivity in adsorbing rare earth element ions.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Engineering, Environmental
Katarzyna Burdzy, Andreas Aurich, Steffi Hunger, Renata Jastrazab, Michal Zabiszak, Dorota Kolodynska
Summary: In this study, the effects of citric acid as a biodegradable complexing agent on the sorption process of La(III), Nd(III), and Ho(III) ions were investigated. The adsorption capacity was analyzed by considering factors such as pH, molar ratio, contact time, initial concentrations, and temperature. The results showed that the Purolite S957 chelating ion exchanger had the highest adsorption capacity. The study also evaluated the reusability of ion exchangers and simulated the behavior of fixed bed columns using dynamic experiments.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Juanjuan Ma, Shuyan Li, Jinxi Wang, Shuting Jiang, Balaji Panchal, Yuzhuang Sun
Summary: This study optimized the culture conditions and bioleaching process of Aspergillus niger for the extraction of rare earth elements (REEs) from coal fly ash (CFA). It was found that organic nitrogen sources influenced the morphology and acid production capacity of A. niger, with oxalic acid being the main acid secreted (4.05 mg/L). The initial pH value was identified as the most influential factor affecting the bioleaching process, and by optimizing it, a leaching rate of 30.91% for total REEs in CFA was achieved. The main mechanism of REEs bioleaching by A. niger from CFA was speculated to be proton exchange and organic ligand complexation.
Article
Environmental Sciences
Bin Ji, Wencai Zhang
Summary: This study focused on the recovery of rare earth elements (REEs) from kaolinite through selective leaching and the synthesis of zeolites from the leaching residue. The results showed that the pH static leaching method achieved over 90% leaching of REEs from metakaolinite, while only extracting less than 2% of the major constituents. Zeolites with different compositions were successfully synthesized, and high purity sodalite exhibited superior adsorption capacity for Ce3+ compared to zeolite A. These findings suggest that kaolinite could be a potential source for REE recovery, and the resulting leaching residue could be used for the synthesis of zeolites as promising adsorbents for Ce3+ recovery.
Article
Nanoscience & Nanotechnology
Alexander T. Brown, Kenneth J. Balkus
Summary: There is a need for the development of new solid-phase adsorbents for element extraction from coal ash. High surface area carbon adsorbents are effective in adsorbing rare earth elements, and MFC-O has shown exceptional extraction capabilities for rare earth elements, thorium, and uranium. The binding properties of MFC-O make it an attractive material for selective extraction of rare earth elements from coal ash.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Engineering, Chemical
Xuyi Wei, Xiaohui Mao, Wenqing Qin, Hongbo Zeng, Junwei Han
Summary: In this study, a natural kaolinite loaded onto alginate hydrogel was used to prepare ALG@KLN composites, which achieved efficient recovery of rare earth elements (REEs) using an eco-friendly method. ALG@KLN exhibited high adsorption capacity and reusability, and the adsorption mechanism was mainly through chemical chelation and electrostatic interaction. This research is of great significance for the development of economical and eco-friendly REE adsorbents.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Environmental Sciences
Yinzhi Lv, Lin Chen, Anning Zhang, Guodong Sheng, Qing Liao
Summary: The separation and recycling of rare earth elements (REEs) are important due to their high demand, limited resources, specific uses, and environmental issues. In this study, two-dimensional Ti3C2Tx MXene was used to remove Nd(III) and La(III) REEs from water, and its physicochemical properties were investigated. Various parameters and adsorption kinetics and isotherms were examined. The results showed that Ti3C2Tx MXene has a great potential for extracting REEs from an aqueous solution.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Chemistry, Applied
Xiaoru Zhao, Xinyu Jiang, Dongming Peng, Jie Teng, Jingang Yu
Summary: Three-dimensional graphene oxide-tris(4-aminophenyl)amine (GO-TAPAx:y) composites with different GO-to-TAPA mass ratios were prepared and characterized for their adsorption capacities of rare earth elements (REEs). The results indicate that the introduction of specific molecules enhances the adsorption ability of the composites, making them feasible for the enrichment of REE ions in real samples.
JOURNAL OF RARE EARTHS
(2021)
Article
Engineering, Chemical
Lingxian Han, Yu Peng, Jiutong Ma, Zhan Shi, Qiong Jia
Summary: This study for the first time employed copolymer precursors to construct HCPs and successfully applied them to the adsorption of REEs, laying a foundation for further design and application of various HCPs in the field of adsorption.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Environmental
Yalin Yang, Qiuting Yan, Xiulan Weng, Gary Owens, Zuliang Chen
Summary: In this study, iron nanoparticles (FeNPs) synthesized from euphorbia cochinchinensis extracts were successfully used for selective recovery of rare earth elements (REEs) from mining wastewater. The FeNPs showed high selectivity for Y(III) and Ce(III) compared to Zn(II) due to selective adsorption and ion exchange mechanisms. The FeNPs exhibited excellent reusability, making them a potential high-quality selectivity material for recovering REEs from mining wastewaters.
Article
Biochemistry & Molecular Biology
Ahmed M. Shahr El-Din, Moubarak A. Sayed, Tarek M. Monir, Nesreen M. Sami, Amal M. I. Aly
Summary: A novel alginate complex was developed for selective separation of molybdenum from rare earth elements, showing excellent adsorption capacity and recovery performance for Mo(VI) ions. The material was characterized and investigated, confirming its potential for selective separation of molybdenum from REEs-containing solutions and demonstrating good reusability over multiple cycles. The adsorption mechanism was elucidated to be governed by electrostatic interaction and ion exchange.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Article
Engineering, Chemical
Qiuting Yan, Zhenjun Zhang, Zuliang Chen
Summary: In this study, microbial synthesized iron nanoparticles after the recovery of rare earth elements (FeNPs/REEs) were used as an environmentally friendly material to remove arsenic from mine groundwater. The removal efficiencies of FeNPs/REEs were higher than those of FeNPs, and the removal mechanism involved surface complexation, oxidation, electrostatic, and ion exchange. The study provides new insights into the use of FeNPs/REEs for groundwater remediation.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Chemistry, Applied
Xiaorui Wang, Wei Cheng, Renda Xu
Summary: This study investigates the adsorption behaviors of rare earth elements (REY) on organic matter in coal through leaching tests and molecular simulation calculations. The results show that the organic matter in coal has a strong adsorption capacity for heavy rare earth elements (HREY) compared to light rare earth elements (LREY). The molecular simulation calculations also confirm the advantage of HREY in adsorption on organic matter. These findings are of great significance for the application of rare earth elements in coal-based resources.
JOURNAL OF RARE EARTHS
(2023)
