Hydrometallurgy最新文献

{"title":"Separation of thorium using new solvent extractant derived from recycling discarded plastic bottles","authors":"Ahmed Orabi ,&nbsp;Hend Salem ,&nbsp;Nagwa Falila ,&nbsp;Doaa Ismaiel ,&nbsp;Magd Badr","doi":"10.1016/j.hydromet.2025.106533","DOIUrl":"10.1016/j.hydromet.2025.106533","url":null,"abstract":"<div><div>Due to the non-biodegradable nature of plastic bottle waste, this work offers a method to recycle this waste by converting it into a valuable and efficient extractor for thorium separation from spent ore. A new promising extractant (Rec-UPEST) was successfully synthesized based on the glycolysis of plastic bottle waste by utilizing a mixture of glycerol and diethylene glycol, followed by esterification using the natural fatty acid of linolenic acid. Several characterizations, such as FTIR spectrometry, ¹H NMR analysis, and MS analysis, were performed to ensure its felicitous preparation. The produced material (Rec-UPEST) dissolved in CHCl₃ could extract Th(IV) efficiently with the maximum loading capacity of 1.08 g L⁻¹ at 15 min, organic to aqueous ratio = 1:1, <em>T</em> = 298 K, and pH = 2. Infrared data confirmed that the extraction was achieved by the bonding of the extractant to the thorium through glycol and ester oxygen atoms. The slope analysis technique inferred that Rec-UPEST has been able to extract Th as a complex with a 2:1 (Rec-UPEST: Th) molar ratio. In two stages, as shown by the resulting McCabe-Thiele diagrams, Th can be successfully extracted and stripped. Thermodynamic calculations showed that Rec-UPEST /Th extraction is an exothermic process. The stripping process of Th (99.8 %) was achieved using 2 mol L⁻¹ HNO₃. To compile all of the recovery steps of Th from the waste residue of the mineralized microgranite dike used in this research, a proposed flow diagram was created.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106533"},"PeriodicalIF":4.8,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144621881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling the leaching behaviour and particle-size distribution dynamics of poly-disperse particulate solids in a batch reactor","authors":"Pavel Raschman,&nbsp;Ľuboš Popovič,&nbsp;Maryna Kyslytsyna,&nbsp;Gabriel Sučik","doi":"10.1016/j.hydromet.2025.106532","DOIUrl":"10.1016/j.hydromet.2025.106532","url":null,"abstract":"<div><div>A material-balance model for the leaching of poly-disperse particulate solids, combining the particle size distribution (PSD) and the shrinking particle model (SPM), has been proposed. This model was applied to the leaching of crude natural magnesite (CNM) with dilute HCl solutions. A CNM sample with wide PSD was used to determine the values of apparent reaction order (0.31) and activation energy (51.5 kJ mol⁻¹) from measured data, and to develop a simulation model. Another CNM sample, with identical chemical and phase composition but different PSD, was subsequently used to experimentally investigate how the degree of conversion and PSD change with the leaching time, and to validate the simulation model. Comparison of the experimental and simulation results showed that (a) the kinetic parameter values obtained by the proposed method characterise the intrinsic chemical reaction on the liquid-solid phase interface, regardless of the PSD; and (b) the proposed model can predict how the degree of conversion and PSD of a poly-disperse particulate solid change during the leaching in a batch reactor.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106532"},"PeriodicalIF":4.8,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144595488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Choline chloride-lactic acid-ascorbic acid (ChCl-LA-AA) based green deep eutectic solvent for leaching LiMn2O4 cathode material of spent Li-ion batteries","authors":"Jasreen Kaur Jasmel Singh ,&nbsp;Masud Rana ,&nbsp;Md Ishtiaq Hossain Khan ,&nbsp;Young Tae Jo,&nbsp;Jeong-Hun Park","doi":"10.1016/j.hydromet.2025.106529","DOIUrl":"10.1016/j.hydromet.2025.106529","url":null,"abstract":"<div><div>The application of lithium manganese oxide (LMO) as a cathode material in Li-ion batteries (LIBs) is increasing due to its affordability, safety, nontoxicity, and high energy storage capabilities. Although its use in electric vehicles (EVs) and portable devices is proliferating, research on recycling valuable metals from spent batteries of this type remains limited. Therefore, this study investigates the recycling of lithium (Li) and manganese (Mn) from spent LiMn₂O₄ cathode materials using a choline chloride and lactic acid (ChCl-LA) deep eutectic solvent (DES) in the presence of various reducing agents such as ascorbic acid (AA), glucose, and formic acid (FA). The compositions of the spent cathode LiMn₂O₄ material, solid residue, and the leachate obtained post-leaching were analyzed using ICP-OES, XPS, SEM-EDS, and XRD analyses. Results indicated that about 100 % leaching efficiencies of both Li and Mn metals were achieved at 90 °C, 1 h, 20 g/L solid-to-liquid ratio and a 1:2:1 M ratio of ChCl-LA-AA. The XRD analysis results showed the presence of minor peaks of manganese oxide in the solid residues obtained from glucose and FA leaching, while the LiMn₂O₄ peaks are absent after the treatment of AA, confirming the effective extraction of metallic elements. Meanwhile, the SEM-EDS analysis showed the raw LiMn₂O₄ material had agglomerated nanoparticles, while the solid residues exhibited increased porosity and reduced Mn content (26.1 wt% for glucose and 23.9 wt% for FA). The solid residue obtained after leaching with AA showed a significant increase in carbon content (82.1 %) and a decrease in Mn (1.42 %). The XPS spectra further confirmed the reduction of manganese (III) or manganese (IV) oxidation states into manganese (II) state and almost complete leaching of Mn and Li. Finally, a detailed mechanism for Mn and Li leaching from the spent LiMn₂O₄ was proposed. The recycling process applied in this study is shown to be feasible and promising for broader application.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106529"},"PeriodicalIF":4.8,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Arsenic precipitation and bioscorodite crystallization from acidic metallurgical wastewater under different bioreactor schemes: In-silico performance analysis","authors":"Evelyn Gaxiola-Muñiz ,&nbsp;Ricardo Aguilar-López ,&nbsp;Sergio A. Medina-Moreno ,&nbsp;Edgar N. Tec-Caamal","doi":"10.1016/j.hydromet.2025.106531","DOIUrl":"10.1016/j.hydromet.2025.106531","url":null,"abstract":"<div><div>Arsenic removal from water is still a challenge to overcome, and the biologically induced formation of scorodite offers an effective approach for treating arsenic-containing effluents from the metallurgical industry. This paper presents a model-based analysis of the dynamics of the overall bioscorodite process under different bioreactor schemes. For this purpose, a modified model was experimentally validated obtaining 0.87 &lt; R² &lt; 0.99 for all variables with <em>p</em>-values &lt;0.001. The validated model was able to adequately predict the dynamics of each variable, which were verified by experimental observations. Subsequently, batch, fed-batch, combined batch/continuous, single-stage, and multi-stage continuous bioreactors were investigated through simulations, testing operational variables that influence the arsenic removal capacity, such as inoculum, ion concentration, dilution rate, and seeding. A comparative basis was then established to identify the bioreactor setups that enhance the arsenic immobilization as a bioscorodite. Single-stage and cascade bioreactors had high arsenic precipitation rates (up to 3.2 g L⁻¹ d⁻¹) and crystal sizes around ∼150 μm. Results showed that three reactors connected in series were able to precipitate 87 % arsenic with a high fed concentration (6.2 g L⁻¹), while a higher number of serial reactors may increase conversion but affect negatively the practicality and feasibility of the system. Combined batch/continuous scheme was useful to obtain large crystal sizes, up to 225 μm. These findings underscore the effectiveness of a model-based design for bioscorodite crystallization process, providing a promising and scalable solution for arsenic removal from industrial effluents.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106531"},"PeriodicalIF":4.8,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precipitation of rare earth phosphates through apatite leach as by-product of nitrophos acid from unconventional phosphate deposit of carbonatite, Malakand, Pakistan","authors":"Farva Arshad ,&nbsp;Munirah Atique Khan ,&nbsp;Attiqa Nasir ,&nbsp;Muhammad Haider Ali ,&nbsp;Lubna Basit ,&nbsp;Muhammad Nasir Siddique ,&nbsp;Muhammad Nadeem","doi":"10.1016/j.hydromet.2025.106530","DOIUrl":"10.1016/j.hydromet.2025.106530","url":null,"abstract":"<div><div>The igneous carbonatite apatite ore of Sellai Patti (Malakand, Pakistan) was beneficiated through mineral processing methods (crushing, grinding, gravity separation, and magnetic separation). The concentrate [Ca₅(PO₄)₃, F] (30 % P₂O₅, 0.7 % REEs) was leached with 65 % nitric acid (S/L 0.42, 65 °C, 700 rpm). The leachate (2.78 g/L REEs, 154 g/L P₂O₅) yielded a 92 % recovery of REEs. Precipitation of REEs was performed with 33 % ammonia solution by two different methods. The direct precipitation process (DPP), produced REE precipitates (34 %) at a pH of 0.2–0.5 with a subsequent hot washing. The remaining filtrate, after precipitation, contained REEs at a low concentration of 0.2 g/L, 97 g/L P₂O₅ and calcium up to 102 g/L. In the nitrophos precipitation process (NPP), a pre-concentration of REEs from 2.8 g/L to 4.1 g/L was observed through the removal of dissolved calcium in the form of calcium nitrate tetrahydrate (CNTH) as a result of freezing the leachate at −20 °C. The precipitates (9 % REEs) obtained at pH 1.7 followed by its re-dissolution in 65 % nitric acid (S/L 1:10) and overnight recrystallization with 50 % excess oxalic acid enhanced REEs concentration up to 30 %. The leftover nitrophos acid (NP acid), a precursor of nitrophos fertilizer, contained only &lt;1 mg/L of REEs, 135 g/L of P₂O₅, and up to 40 g/L of calcium. The present research advances a sustainable and efficient methodology for the extraction of REEs through an innovative and significantly effective DPP.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106530"},"PeriodicalIF":4.8,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leaching kinetics of molybdenite with layered structure and hydrophobic properties in the H2SO4-H2O2-H2O system at atmospheric pressure","authors":"Zhiyuan Chen ,&nbsp;Zihui Jiang ,&nbsp;Qiu Hu ,&nbsp;Jiangtao Li","doi":"10.1016/j.hydromet.2025.106527","DOIUrl":"10.1016/j.hydromet.2025.106527","url":null,"abstract":"<div><div>Previous studies on the leaching kinetics of molybdenite were primarily based on processing data using a contraction core model with spherical mineral particles. However, molybdenite particles exhibit a thin plate and layered structure. In this study, a model of circular particles was employed to derive the kinetic equation. The apparent activation energies of the molybdenite leaching reaction, both without mechanical activation and with mechanical activation treatment, were calculated as 55.3 kJ/mol and 49.5 kJ/mol, respectively. The layered structure of molybdenite renders its mineral particles challenging to grind during the ball milling process. Nonetheless, this process enhanced the active point of the mineral to a certain extent, thereby facilitating the leaching reaction. The rate-limiting step of the leaching reaction was identified as the chemical reaction step. Specifically, the reaction order of H₂SO₄ and H₂O₂ were determined as 0.063 and 0.959, respectively. Notably, variations in the H₂O₂ concentration exerted a significant impact on the leaching effect, while changes in the concentration of H₂SO₄ exhibited a relatively smaller effect. Additionally, molybdenite exhibited strong hydrophobic properties. The addition of surfactants improved the reaction environment and enhanced the leaching effect. The expression for leaching kinetics was defined as follows:<span><span><span><math><mn>1</mn><mo>−</mo><msqrt><mrow><mn>1</mn><mo>−</mo><mi>α</mi></mrow></msqrt><mo>=</mo><msub><mi>k</mi><mi>r</mi></msub><mi>t</mi><mo>=</mo><mn>7.73</mn><mo>×</mo><msup><mn>10</mn><mn>3</mn></msup><msubsup><mi>r</mi><mn>0</mn><mrow><mo>−</mo><mn>1</mn></mrow></msubsup><msubsup><mi>C</mi><mrow><mi>H</mi><mn>2</mn><mi>SO</mi><mn>4</mn></mrow><mn>0.063</mn></msubsup><msubsup><mi>C</mi><mrow><mi>H</mi><mn>2</mn><mi>O</mi><mn>2</mn></mrow><mn>0.959</mn></msubsup><msup><mi>e</mi><mrow><mo>−</mo><mfrac><mn>59706</mn><mi>RT</mi></mfrac></mrow></msup><mi>t</mi></math></span></span></span></div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106527"},"PeriodicalIF":4.8,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of hydrogen gas formation during leaching of weakly radioactive ores of the Tomtor deposit: Geo-radiochemical nature of the reducing properties of the ore","authors":"Vladimir I. Kuzmin,&nbsp;Dmitrii V. Kuzmin,&nbsp;Oleg A. Epov,&nbsp;Timur Yu. Ivanenko","doi":"10.1016/j.hydromet.2025.106523","DOIUrl":"10.1016/j.hydromet.2025.106523","url":null,"abstract":"<div><div>Direct alkaline leaching of weakly radioactive rare metal ores of the Tomtor deposit (Russia) was investigated. It was found that the process of leaching monazite with sodium hydroxide solutions in the presence of various associated mineral components is accompanied by the release of significant amounts of hydrogen and the formation of stable foam filling the reactor and preventing the elimination of hazardous gas. The discovered phenomenon is unique, since hydrogen release occurs at a high rate even at low temperatures (40–50 °C) and when leaching ores in both alkaline and acidic environments (hydrofluoric acid solutions). It is assumed that the high reduction potential of the ores is associated with the deaeration of mineral components (oxygen removal) during their long-term radiochemical irradiation. Preliminary studies using solid-state NMR confirmed this assumption. A significant amount of hydride ions, which are part of stable mixed cluster compounds of aluminum oxides and phosphates, were found in ore samples. It is assumed that the high stability of the foam formed in this process is due to the formation of a structural and mechanical barrier of hydrophobic pulp particles, including un-decomposed pyrite. Undesirable foaming is eliminated by adding an anionic surfactant (sodium stearate) to the pulp, which ensures the removal of hydrophobic particles from the surface of gas bubbles.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106523"},"PeriodicalIF":4.8,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The use of hydrophobic deep eutectic solvent dodecanoic acid/menthol as a sustainable diluent for the continuous extraction process of Fe and Ti separation","authors":"Nikita A. Milevskii,&nbsp;Dmitriy V. Lobovich,&nbsp;Arina V. Milevskaya,&nbsp;Yulia A. Zakhodyaeva,&nbsp;Andrey A. Voshkin","doi":"10.1016/j.hydromet.2025.106526","DOIUrl":"10.1016/j.hydromet.2025.106526","url":null,"abstract":"<div><div>Hydrophobic deep eutectic solvents (HDES) have long been used for the extraction of metal ions from aqueous systems. This study proposes the use of HDES composed of dodecanoic acid and menthol as a diluent for tributyl phosphate (TBP), which serves as the extractant. The results demonstrate that the extraction system developed remains stable across a broad range of TBP concentrations and possesses excellent physical properties, making it suitable for laboratory-scale extraction equipment. By examining the extraction of iron and titanium ions, key dependencies of extraction efficiency were identified as varying acidity levels, volume ratios, initial metal concentrations and conditions for effective stripping. Notably, the efficiency of the extractant remained unchanged after ten cycles of extraction and stripping, particularly for titanium ions extracted from 10 mol/L hydrochloric acid. This indicates the chemical stability of the proposed extraction system. A continuous separation process for iron and titanium was successfully implemented on laboratory extraction equipment using liquid pseudomembranes, achieving an efficiency greater than 95 % of the theoretical maximum. These findings suggest that HDES have significant potential for use as non-volatile, non-combustible and renewable solvents in extraction processes.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106526"},"PeriodicalIF":4.8,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144490604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the effectiveness of iron oxide (Fe3O4) nanoparticles vs. traditional chloride methods for copper cementation and recovery from industrial waste solutions by aluminium","authors":"Cecilia Daniela Costa ,&nbsp;María José Hernandez Triana ,&nbsp;Mario Avila ,&nbsp;Virginia Emilse Diz ,&nbsp;Graciela Alicia González","doi":"10.1016/j.hydromet.2025.106528","DOIUrl":"10.1016/j.hydromet.2025.106528","url":null,"abstract":"<div><div>The cementation of copper on aluminium is a well-studied process, typically facilitated by chloride ions to overcome the insulating aluminium oxide layer. This study presents an alternative approach using magnetite (Fe₃O₄) nanoparticles as electron (redox) mediators, allowing the cementation process to occur despite the presence of the aluminium oxide layer. After optimizing the concentration of the Fe₃O₄ suspension, the pH, and the reaction time, the performance of this method was compared to the classical chloride ion-based approach. The nanoparticle assisted method achieved higher recovery (%) of copper, but at a slower pace. This difference in reaction speed explains the more compact, non-oxidize copper deposits observed by SEM and DRX, in contrast to the dendritic and airy deposits with a high fraction of Cu₂O obtained using the classical chloride method. Under optimized conditions, the method was applied for the recovery of Cu from two industrial PCB solutions, achieving excellent recoveries after adjusting the pH.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106528"},"PeriodicalIF":4.8,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144501080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recovery process of rare earths, Al, U, and Th from ionic rare earth purification residue using sequential alkaline leaching, acid leaching solvent extraction and stripping","authors":"Qiaofa Lan ,&nbsp;Xiaolin Zhang ,&nbsp;Fei Niu ,&nbsp;Donghui Liu ,&nbsp;Youming Yang","doi":"10.1016/j.hydromet.2025.106524","DOIUrl":"10.1016/j.hydromet.2025.106524","url":null,"abstract":"<div><div>Ionic rare earth purification residue (PR) originates from refining of ionic rare earth ores and is predominantly composed of rare earth elements (REEs), aluminum (Al), and silicon (Si). This is a recyclable secondary resource. It provides substantial challenges due to its classification as low-level radioactive waste (LLW). Recognizing the distinctive properties of PR, this paper describes a highly efficient process for the recovery and enrichment of Al, REEs, uranium (U), and thorium (Th) through a multistep process encompassing alkali digestion, hydrochloric acid leaching, sole extractant enrichment and separation. At a controlled temperature of 70 °C, the Al digestion efficiency reached 88.9 %. The alkali digestion residue underwent hydrochloric acid leaching, yielding leaching efficiencies of 99.9 %, 99.4 %, and 99.0 % for REEs, U(VI), and Th(IV), respectively. Notably, the amount of insoluble residue was reduced by 90 %, and it was transformed from LLW into general solid waste residue. Additionally, the utilization of 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester (HEHEHP) as the sole extractant provided 100 % extraction efficiencies for U(VI) and Th(IV). After stepwise stripping processes, the purities of both U(VI) and Th(IV) exceeded 90 %. The REEs were precipitated as RE₂(C₂O₄)₃ and subsequently calcined to produce rare earth oxides with a recovery of 90.1 % and a purity of 97.4 %. This comprehensive scheme addressed the persistent challenges associated with long-term storage and radiological environmental risk.</div></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"236 ","pages":"Article 106524"},"PeriodicalIF":4.8,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}