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
Environmental Sciences
Liqing Li, Chenhao Liu, Hepeng Zhang, Bin Huang, Bing Luo, Chao Bie, Xiaoqi Sun
Summary: This study successfully achieved impurities removal and enrichment of rare earth elements in ion-adsorbed type rare earth ore by using specific materials. The method reduces the loss rate of rare earth elements and improves product purity, while also benefiting environmental protection and resource recycling.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Engineering, Chemical
Sait Kursunoglu, Shokrullah Hussaini, Soner Top, Zela Tanlega Ichlas, Hasan Serkan Gokcen, Safak Ozsarac, Muammer Kaya
Summary: The research focused on the production process of mixed rare earth oxide powder from thorium-containing bastnasite ore, demonstrating efficient dissolution of various rare earth elements and thorium under specific conditions.
Article
Chemistry, Analytical
Justine Basque, Janyce Lavoie, Nicolas Reynier, Dominic Lariviere
Summary: A new cloud point extraction (CPE) method using a chelating agent and surfactants was developed for selectively extracting and concentrating thorium from sulfuric acid leachate. The method achieved over 98% thorium extraction and a preconcentration factor of 22. This study is the first to demonstrate CPE's effectiveness in separating Th(IV) from rare earth elements and U in mining leachates.
MICROCHEMICAL JOURNAL
(2023)
Article
Metallurgy & Metallurgical Engineering
John Demol, Elizabeth Ho, Karin Soldenhoff, Inna Karatchevtseva, Gamini Senanayake
Summary: The addition of iron minerals to the monazite acid bake process significantly increased the leaching of rare earth elements and thorium, especially at temperatures above 300 degrees C. The presence of iron minerals led to the formation of an amorphous and insoluble iron sulfate-polyphosphate type phase, which enhanced the dissolution of rare earth elements and thorium compared to monazite alone.
Article
Geochemistry & Geophysics
Vitor L. Gontijo, Leandro Augusto Viana Teixeira, Virginia Sampaio Teixeira Ciminelli
Summary: This work investigates the effect of sulfuric acid baking on the extraction of rare earth elements (REE) from waste rock samples from a phosphate mine. The study highlights the role of different mineralogical assemblages, weathering degree, and the behavior of impurities (iron, phosphorus, and calcium) on REE extraction. The optimal conditions for selective leaching of REE were found to be sulfuric acid baking at 25°C for 15 minutes with an H2SO4:sample (w/w) mass ratio of 0.45:1. Iron-rich samples showed reduced REE extraction and increased iron dissolution with increasing temperature, while higher REE and lower iron extraction were observed with a higher sulfuric acid/sample mass ratio (0.95:1). Calcium-rich samples exhibited lower REE extraction due to the entrapment of REE-bearing minerals by a gypsum layer and the uptake of lanthanides by calcium sulfate compounds formed during leaching.
Article
Engineering, Environmental
Dezhi Hu, Baozhong Ma, Yubo Liu, Qinqing Zhao, Yingwei Lv, Chengyan Wang, Yongqiang Chen
Summary: A process combining sulfuric acid baking and water leaching was proposed for the efficient treatment and extraction of lithium, aluminum, and phosphorus from montebrasite. The leaching rates of Li, Al, and P reached more than 96%. This process is characterized by low energy consumption, high comprehensive recovery rates of valuable elements, and environmental friendliness.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Energy & Fuels
Vinoth Kumar Kuppusamy, Maria Holuszko
Summary: The applicability of sulfuric acid baking followed by water leaching (ABWL) for enhancing rare earth element (REE) leaching recovery from coal tailings was investigated in this study. The results showed that ABWL significantly improved REE extraction, reaching around 80% recovery. During the ABWL process, rare earth minerals in the sample were transformed into easily soluble rare earth sulfates.
Article
Engineering, Chemical
Ahmed H. Orabi, Basma T. Mohamed, Doaa A. Ismaiel, Salah S. Elyan
Summary: Monazite mineral is the main source of uranium and thorium, which are mainly associated with rare earth elements. Selective extraction of uranium and thorium was achieved using dipropylamine, with thermodynamic analysis indicating an exothermic process. This method allows for the preparation of marketable pure thorium and uranium products in addition to rare earth concentrate.
MINERALS ENGINEERING
(2021)
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
Engineering, Environmental
Ghazaleh Shakiba, Roozbeh Saneie, Hadi Abdollahi, Ehsan Ebrahimi, Ali Rezaei, Mohsen Mohammadkhani
Summary: In this paper, deep eutectic solvents (DESs) were applied as a green replacement for conventional solvents in the leaching process of REEs from monazite. The DES comprised of 2ChCl:1PTSA exhibited the highest extraction efficiency.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Bo Dong, Qinghua Tian, Xueyi Guo, Qingao Wang, Zhipeng Xu, Dong Li
Summary: This study explored the leaching behavior of scandium from limonitic laterites under sulfation roasting-water leaching (SAL). The roasting temperature was found to significantly affect the leaching efficiency of scandium, with the optimum conditions being 600 degrees C roasting for 2 hours using a sulfuric acid/laterite ratio of 1/4. Compared to other methods, the SAL process offers lower costs and acid consumption for the enrichment of scandium.
JOURNAL OF SUSTAINABLE METALLURGY
(2022)
Article
Metallurgy & Metallurgical Engineering
Wei Ding, Shenxu Bao, Yiming Zhang, Junhui Xiao
Summary: This study explores the highly selective process steps for extracting Scandium from red mud, and achieves high leaching efficiency under optimal conditions. The sulfation-roasting-water leaching process proves to be a promising and commercially viable technique.
MINERAL PROCESSING AND EXTRACTIVE METALLURGY REVIEW
(2023)
Article
Green & Sustainable Science & Technology
Jinhe Pan, Behzad Vaziri Hassas, Mohammad Rezaee, Changchun Zhou, Sarma V. Pisupati
Summary: A sequential chemical roasting, water leaching, and acid leaching process was developed for the recovery of REEs from coal fly ash. Adding NaOH and Na2CO3 proved to be effective in converting the glassy phases in the ash into water or acid soluble phases, enhancing the recovery of REEs.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Engineering, Environmental
Boyi Xie, Chaxiang Liu, Bohan Wei, Ruixiang Wang, Rushan Ren
Summary: Waste phosphors, containing rare earth and toxic metals, are difficult to extract cerium and terbium due to their unique structure. This study developed a simple process for recovering rare earth elements from waste phosphors. By alkali roasting with NaOH as the additive, the aluminum-magnesium spinel structure was destroyed. A controlled potential reduction leaching process using FeCl2 as the reductant achieved high leaching efficiencies for Y, Eu, Ce, and Tb. This research provides a theoretical and technical basis for the recycling of waste phosphors.
Article
Metallurgy & Metallurgical Engineering
Arsyad Maulana Dzulqornain, Ana Belen Cueva-Sola, Kyeong Woo Chung, Jin-Young Lee, Rajesh Kumar Jyothi
Summary: This study presents a hydrometallurgical process for the separation of light rare earth elements (LREEs) using oxidation, precipitation, solvent extraction, and stripping techniques. Selective oxidation with potassium permanganate was employed for the separation of cerium (III). Solvent extraction with Cyanex 572 and cross-current scrubbing were used to achieve the separation of lanthanum (III) from neodymium (III) and praseodymium (III).
Article
Metallurgy & Metallurgical Engineering
Bo Chen, Shenxu Bao, Yimin Zhang
Summary: This study investigated the effects of Al, Fe, P, Si and Na on the precipitation characteristics of vanadium in the ultrasound precipitation system. The concentration upper limits and the negative influence on the precipitation kinetics were determined for each impurity. The findings provide theoretical and technical support for the industrial application of ultrasound precipitation technology.
Article
Metallurgy & Metallurgical Engineering
Chunlin He, Mingwei Qi, Yun Liu, Zunzhang Liu, Yuezhou Wei, Toyohisa Fujita, Guifang Wang, Shaojian Ma, Wenchao Yang, Junyuan Gan
Summary: In this study, D201 x 7 resin and tartaric acid were used as materials and complexing agents for the separation of germanium from sulfuric acid solution. The study successfully achieved the separation of germanium and demonstrated the high selectivity and adsorption performance of the resin.
Article
Metallurgy & Metallurgical Engineering
Xiaobo Zhu, Yue Liu, Chen Ma, Wang Li
Summary: A selective and highly effective method for the extraction and separation of V(IV) and Fe(III) using N235 and P507 as solvent extractants is proposed. The pH, composition, and concentration of the extractant mixture have significant effects on the extraction efficiency and separation factor. The mixing of P507 and N235 generates the P507 monomer, which enhances the extraction efficiency and weakens the stability of vanadium containing extraction complex. Cation exchange process forms the extraction complexes.
Article
Metallurgy & Metallurgical Engineering
B. Behnajady, J. Yousefi Seyf, S. Karimi, M. Moradi, M. Sohrabi
Summary: Deep eutectic solvents (DES) have potential as environmentally-friendly solvents for recovering metals from spent lithium-ion batteries (LIBs). Experimental and molecular dynamics simulation results showed that the chloride ions in DES can form complexes with lithium, manganese, and nickel ions, facilitating their extraction.
Review
Metallurgy & Metallurgical Engineering
Sebastian Kinas, Dorota Jermakowicz-Bartkowiak, Anna Dzimitrowicz, Piotr Cyganowski
Summary: The high demand for platinum-group metals (PGMs) and Re in economical and industrial applications related to environmental protection and energy conversion/storage has led to resource scarcity. Thus, it is crucial to recover and recycle these rare metals. This study critically reviews the recent progress in the effective recovery of PGMs and Re from materials relevant to sustainable technologies, emphasizing practical aspects, environmental impact, and issues related to the unit processes of recovery.
Article
Metallurgy & Metallurgical Engineering
Guopeng Yang, Qinggang Li, Guiqing Zhang, Mingyu Wang, Zuoying Cao, Wenjuan Guan, Jiawei Du, Shengxi Wu
Summary: The study proposes an efficient, clean, and economical process for recovering V2O5 from titanium-white waste through hydrogen peroxide stripping and precipitation of vanadium products by heating. Experimental results show that the use of D2EHPA as a modifier prolongs the duration of maximum stripping efficiency, enabling continuous operation.
Article
Metallurgy & Metallurgical Engineering
Guisu Yu, Shuainan Ni, Yun Gao, Ditang Mo, Zhiyuan Zeng, Xiaoqi Sun
Summary: This research proposes a novel green process for the selective recovery of rare earth elements (RE) from spent NdFeB permanent magnet using hydrophobic deep eutectic solvent (HDES). Through optimization of extraction conditions and stripping method, efficient and clean separation and recovery have been achieved.
Article
Metallurgy & Metallurgical Engineering
Jia Li, Xinsheng Wu, Xiaozhou Zhou, Li Zeng, Shengxi Wu, Mingyu Wang, Wenjuan Guan, Zuoying Cao, Qinggang Li, Guiqing Zhang
Summary: This paper presents a complete hydrometallurgical route for the full-component utilization of deep-sea polymetallic nodules (DPN), achieving high recovery efficiency and near-zero waste production with low energy consumption.
Article
Metallurgy & Metallurgical Engineering
Sanae Elmisaoui, Abderrazak M. Latifi, Lhachmi Khamar
Summary: A first principles model is developed to describe the dissolution mechanism of phosphate ore particles in a solution of phosphoric acid. The model accounts for non-uniform size of ore particles using particle size distributions and quantifies their influence on the model predictions. A global estimability analysis is carried out to determine the estimable parameters from experimental data, and the predictions show good agreement with the experimental data. The computed activation energy indicates that diffusion is the rate limiting step of the dissolution process.