Hydrometallurgy最新文献

{"title":"Influence of ionic liquid (R4PSCN) for selective separation and recovery of copper from spent CuCr catalyst leach liquor","authors":"Saroj Sekhar Behera ,&nbsp;Pankaj Kumar Parhi","doi":"10.1016/j.hydromet.2024.106352","DOIUrl":"10.1016/j.hydromet.2024.106352","url":null,"abstract":"<div><p>Separation and recovery of copper (Cu) from sulphate mediated Cu<img>Cr spent catalyst leach solution through solvent extraction approach has been systematically investigated. A number of Ionic Liquid (IL) and other conventional extractants were used while investigating the selectivity and efficient extraction tendency of either IL or extractants towards Cu(II). In context of copper extraction efficiency, the adopted organic reagents followed the descending order: R₄PSCN &gt; R₄PD &gt; R₄PCy &gt; Cyphos 101 &gt; Aliquot 336 &gt; D2EHPA &gt; Cyanex 272. The extraction behavior of Cu(II) was established based on slope analysis method. From the results it was noticed that extraction occurs through a cation exchange mechanism with association of a mole of Cu(II) per mole of R₄PSCN. The plot of log D vs. log [R₄PSCN] yield a linear relationship with a slope close to 4 which is used to propose extraction reaction mechanism/ stoichiometry. The nature of complex between Cu(II) and IL was further examined using FTIR analysis of the loaded organic phase with the diluent. Mc-Cabe Thiele diagram was constructed to predict quantitative extraction of Cu(II) which revealed the need for two stages at aqueous to organic (A:O) phase volume ratio of =3:1. The stripping isotherm constructed at optimum NH₄OH concentration (0.4 M) suggests the need for two stages at O:A phase volume ratio of = 2:1 for complete stripping of copper with regeneration of R₄SCN for further use. Both isotherm conditions were validated by 6 cycles of counter current simulation (CCS) study for obtaining the desired amount of Cu(II) loaded R₄SCN (during extraction) and/or stripped copper solution (during stripping). Overall copper enrichment was ∼6 fold leading to produce a copper(II) solution of 48 g/L from 6 g/L Cu(II). The stripped solution was subjected to crystallization study to produce copper sulphate crystals of high purity and was confirmed by XRD analysis of crystal phases.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"228 ","pages":"Article 106352"},"PeriodicalIF":4.7,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141399277","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":"Efficient extraction of lithium from alkaline solution using the synergistic extractants ethylhexyl salicylate and trialkylphosphine oxide in kerosene and stripping with acid","authors":"Zhonghua Niu ,&nbsp;Licheng Zhang ,&nbsp;Ruirui Liu ,&nbsp;Yongquan Zhou ,&nbsp;Lianmin Ji ,&nbsp;Lijuan Li","doi":"10.1016/j.hydromet.2024.106342","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106342","url":null,"abstract":"<div><p>Efficient separation of lithium from alkaline solution with high Na/Li ratio is of great importance for the development of batteries for new energy industry. This work proposes the use of a novel extraction system composed of ethylhexyl salicylate (ES) and trialkylphosphine oxide (TRPO). The equilibrium experiment revealed that the order of metal ions extracted by ES/TRPO extraction system is Mg²⁺ &gt; Ca²⁺ &gt; Li⁺ &gt; Na⁺ &gt; K⁺. A recovery process including extraction, scrubbing, and stripping was designed to recover lithium from a solution of 3.25 g/L Li, 52 g/L Na and 0.8 mol/L OH⁻. More than 99% of lithium could be extracted to the organic phase. After stripping, a lithium-rich solution containing 25 g/L Li was obtained, and the system showed good stability in the cycling experiments. The FT-IR analysis and DFT calculation were conducted to investigate the extraction mechanism. The results demonstrated that ES mainly coordinates with metal ions through Ph-O and C<img>O bonds to form a hexatomic ring complex, thereby allowing metal ions to enter the organic phase. The calculated binding energies of the complex are highly consistent with the equilibrium experiment. The present work may provide a novel extraction system to efficiently recover lithium from alkaline solution with high Na/Li ratio.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"228 ","pages":"Article 106342"},"PeriodicalIF":4.7,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141286300","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":"Base metals recovery from waste printed circuit board leachate using biogenic hydrogen sulfide gas","authors":"Jonovan Van Yken ,&nbsp;Naomi J. Boxall ,&nbsp;Ka Yu Cheng ,&nbsp;Aleksandar N. Nikoloski ,&nbsp;Navid R. Moheimani ,&nbsp;Anna H. Kaksonen","doi":"10.1016/j.hydromet.2024.106341","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106341","url":null,"abstract":"<div><p>Electronic waste, or e-waste, represents one of the rapidly expanding categories of waste worldwide. By 2019, the global production of e-waste had surged to 53.6 million tons. Due to its substantial metal content, e-waste holds significant financial value, estimated at US$57 billion globally in 2019, predominantly concentrated in printed circuit boards (PCBs). Previous studies have explored hydrometallurgy techniques to extract base metals from PCBs, but effectively recovering these solubilised metals remained a challenge. This research sought to assess metal recovery from PCB waste leachate by utilising hydrogen sulfide generated through a consortium of sulfate-reducing bacteria (SRB) in a fluidised bed reactor (FBR). Both lactate and glycerol were examined as potential organic electron donors for the sulfate reduction. With lactate (1 g L⁻¹) as the electron donor, the FBR achieved an average sulfate reduction efficiency of 62%, with a hydrogen sulfide (H₂S) production rate of 250 mg H₂S-S L⁻¹ d⁻¹ and H₂S-S concentration of 300 mg L⁻¹ in the effluent. When glycerol was the organic electron donor, the average sulfate reduction efficiency was 49%, H₂S production rate was 210 mg H₂S-S L⁻¹ d⁻¹ and H₂S-S concentration was 260 mg L⁻¹. <em>Desulfovibrio</em>, <em>Desulfococcus</em> and <em>Desulfomicrobium</em> were the dominant sulfate reducers in the FBR. The resulting dissolved hydrogen sulfide was employed to recover metals from e-waste leach liquor. Utilising biogenic sulfide and NaOH, a notably high precipitation efficiency (&gt;99%) was attained for aluminum, nickel, copper, and zinc. Additionally, iron, utilised in the e-waste leaching process, was also recovered with an efficiency exceeding 99%. The precipitation of metals occurred within a pH range from 1.5 to 8.5. Overall, this process facilitated the formation of valuable mixed-metal precipitates from waste PCB-derived leachate. These precipitates could undergo further purification or serve as raw material for subsequent processes.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"228 ","pages":"Article 106341"},"PeriodicalIF":4.7,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304386X24000811/pdfft?md5=5c54645e11e05d5f355e7239d8a80307&pid=1-s2.0-S0304386X24000811-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141286114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High efficiency separation of bastnaesite (REFCO3) and monazite (REPO4) in mixed rare earth concentrate by heating under N2 and leaching with HCl/AlCl3","authors":"Jiahao He ,&nbsp;Peng Gao ,&nbsp;Shuai Yuan ,&nbsp;Shaokai Cheng ,&nbsp;Jilai Ning ,&nbsp;Zhenya Zhou ,&nbsp;Yongsheng Sun ,&nbsp;Wenbo Li","doi":"10.1016/j.hydromet.2024.106338","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106338","url":null,"abstract":"<div><p>Bayan Obo mixed rare earth (RE) concentrate is one of the most significant rare earth mineral resources worldwide. However, the concentrated sulfuric acid roasting method, which is commonly used to treat ores, generates pollutants such as waste gas, wastewater, and leach residue, resulting in the squandering of the associated resources. This paper introduces a green process involving selective mineral phase transformation (MPT) by heating, followed by leaching to separate bastnaesite and monazite in a mixed RE concentrate to facilitate their subsequent decomposition or extraction. The effects of the MPT conditions on rare earth extraction were investigated. During the MPT process, bastnasite decomposed into REOF, which is more easily leached, whereas monazite remained unchanged. Under suitable conditions, the leaching efficiency of REOF reached 93.7%, while that of monazite (REPO₄) was only 3.2%. Furthermore, the content of monazite in the leach residue was 91.2%. Compared to the mixed RE concentrate, numerous cracks and pores were generated on the surface and inside the MPT products. Furthermore, the total pore volume and specific surface area significantly increased, which made the reaction between the MPT products and hydrochloric acid more efficient. Thus, the MPT process facilitated the leaching of bastnasite and its separation from monazite.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"228 ","pages":"Article 106338"},"PeriodicalIF":4.7,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141324236","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":"Investigating the mechanism of Au(III) transport using a polymer inclusion membrane with dibutyl carbitol as a carrier","authors":"Meisam Ghiasi ,&nbsp;Mahmoud Abdollahy ,&nbsp;Mahdi Abdollahi ,&nbsp;Mehdi Mohseni","doi":"10.1016/j.hydromet.2024.106339","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106339","url":null,"abstract":"&lt;div&gt;&lt;p&gt;In this article, firstly, the separation and transfer of Au(III) from gold chloride solution was investigated using a polymer inclusion membrane (PIM) system containing dibutyl carbitol (DBC) as carrier molecules, dioctyl phthalate (DOP), bis(2-ethyl hexyl) adipate (dioctyl adipate) (DOA) and tris (2-ethyl hexyl) phosphate (T2EHP) as plasticizers and high molecular weight polyvinyl chloride (PVC) as the base polymer. Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscope (SEM) were used to identify PIMs. Kinetic studies featuring a two-step reaction, with the first step being reversible, were conducted across various sections to investigate the processes of extraction, stripping, and transport. The effects of different stripping agents such as water, HCl, thiourea, sodium thiosulfate, and oxalic acid was investigated, and the best results were obtained with thiourea. Also, the mechanisms of Au(III) extraction and transport were studied. Under the conditions of source solution, tetrachloroaurate anionic complex &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mfenced&gt;&lt;mrow&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;msub&gt;&lt;mi&gt;Cl&lt;/mi&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/mfenced&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; with protonated DBC (&lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mfenced&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mfenced&gt;&lt;mi&gt;ROR&lt;/mi&gt;&lt;/mfenced&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;OH&lt;/mi&gt;&lt;/mrow&gt;&lt;/mfenced&gt;&lt;mfenced&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mfenced&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;) was extracted by ion solvation mechanism. The validity of the proposed extraction mechanism was confirmed through the use of nuclear magnetic resonance (&lt;sup&gt;1&lt;/sup&gt;H NMR) spectroscopy. In order to make the membrane with the best composition and the highest efficiency, the effect of weight percentage of the carrier and plasticizer was investigated. There was an optimal value for the weight percentage of plasticizer (10–20% by weight) and carrier (40%), in which the highest flux and permeability in the membrane occurred. The effect of the viscosity of different plasticizers (DOP, DOA, and T2EHP) on the Au(III) flux was also investigated. It was found that the flux increases linearly with the reduction of plasticizer viscosity. Effect of membrane thickness on the permeability, initial flux, and efficiency of Au(III) transfer, were conducted with thickness of 120, 80, 45, and 30 μm. By reducing the thickness of the membrane, the transfer flux, permeability and percent of Au(III) transport, were improved from 12.9 × 10&lt;sup&gt;−3&lt;/sup&gt; &lt;span&gt;&lt;math&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;, 45.3 × 10&lt;sup&gt;−7&lt;/sup&gt; &lt;span&gt;&lt;math&gt;&lt;mi&gt;mol&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; and 18.2% to 26.4 × 10&lt;sup&gt;−3&lt;/sup&gt; &lt;span&gt;&lt;math&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mi&gt;h&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;, 83.5 × 10&lt;sup&gt;−7&lt;/sup&gt; &lt;span&gt;&lt;math&gt;&lt;mi&gt;mol&lt;/mi&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;msup&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;m","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"227 ","pages":"Article 106339"},"PeriodicalIF":4.7,"publicationDate":"2024-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141243703","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":"Hollow drop bubbles: A preliminary study of simplified prototype for improving copper(II) extraction with ACORGA® M5640 using coated bubble swarm","authors":"Diego Poblete ,&nbsp;Claudio Leiva ,&nbsp;María Sinche-Gonzalez ,&nbsp;Claudio Acuña","doi":"10.1016/j.hydromet.2024.106340","DOIUrl":"10.1016/j.hydromet.2024.106340","url":null,"abstract":"<div><p>There are two well-defined processes for the types of copper ores. One for the processing of copper sulfides and another for the processing of the copper oxides. There are similarities between the two, particularly in the preparation stage of the run of mine (ROM) such as the crushing. However, significant differences exist in how to concentrate the elements of interest. Flotation is the most used concentration process to separate copper sulfide minerals from other minerals using air bubbles. For oxides, after the dissolution of copper, the solvent extraction (SX) process is the preferred path using two immiscible liquids to separate the copper.</p><p>A line of investigation for solvent extraction is the use of a bubble coated with solvent to extract the metal of interest from the aqueous solution, some devices have been built and tested for this purpose using different principles to generate a coated bubble swarm. However, those equipments have been tested on laboratory and have not been scaled up to an industry level.</p><p>The Hollow Drop (HD) concept was born from the idea of building a device to generate coated bubbles in a continuous swarm that could be scalable to an industry level. In this paper two columns were built and operated: a proof-of-concept column and a scale-up attempt for the extraction of Cu(II) fom an aqueous solution of 2.5 g L⁻¹ using ACORGA® M5640 (25% <em>v</em>/v) in the Kerosene.</p><p>The results show that we could generate a bubble swarm and conduct the solvent extraction process at a 97% recovery using our proposed coated bubble generator. However, in our scaled prototype test only a 70% recovery was achieved, which shows that our column is working but the scaling-up needs more investigation regarding the dimensions and flows of the process.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"227 ","pages":"Article 106340"},"PeriodicalIF":4.7,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0304386X2400080X/pdfft?md5=c37d7fbb4b8dae3a9d4322e028b88a13&pid=1-s2.0-S0304386X2400080X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141143679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nickel(II) extraction from chloride solutions using N-2-ethylhexylpyridine-3-formamide: A new reagent toward clean hydrometallurgy and a proposed flowsheet for chloride leach liquors of nickel laterites","authors":"Wensen Liu ,&nbsp;Yahui Liu ,&nbsp;Hui Su ,&nbsp;Jian Zhang ,&nbsp;Pengfei Shi ,&nbsp;Jie Liang ,&nbsp;Zhaowu Zhu","doi":"10.1016/j.hydromet.2024.106337","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106337","url":null,"abstract":"<div><p>Base metal hydrometallurgy in a chloride medium has considerable advantages, as metals can be recovered by solvent extraction through a neutral complex mechanism without extra reagent addition, leading to ready lixiviant recycling and significantly reduced wastewater discharge. However, the recovery of Ni(II) using this hydrometallurgical method is challenging because of the unavailability of appropriate extraction reagents. In this study, a new reagent, N-2-ethylhexylpyridine-3-formamide (MEH3), was used to efficiently extract Ni(II) from weakly acidic (pH &gt; 2.5) or neutral chloride solutions in the form of neutral complexes without pH adjustment. Some other metal ions can also be extracted; the selectivity of the reagent for each metal decreased in the following order: Cu(II) &gt; Zn(II) &gt; Ni(II) &gt; Fe(III) &gt; Co(II) &gt; Mn(II). The reagent had weak ability to extract other metal ions such as Ca, Al, Cr(III), Mg, and Li. The extraction of Ni(II) was positively correlated with the Cl⁻ concentration in the aqueous solution, indicating that Cl⁻ is a driving force for Ni(II) extraction. The Ni(II) loaded organic phase was stripped with water, and approximately 50 g/L of Ni(II) in the loaded strip liquor was obtained at an O/A ratio of 15:1. The Ni(II) extraction mechanism was further studied using crystal structure analysis, FT-IR spectroscopy, and the maximum loading capacity. The results showed that a Ni(MEH3)₂Cl₂ complex was formed via Ni(II) extraction. In conclusion, the MEH3 system can selectively extract Ni(II) from a chloride solution without consuming alkaline reagents, and no new substances are produced, which is beneficial for the realization of mother liquor recycling and has a positive impact on clean hydrometallurgy.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"227 ","pages":"Article 106337"},"PeriodicalIF":4.7,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141095475","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":"Optimization of LiF dissolution with Al2(SO4)3 and its application to lithium extraction by fluorination of α-spodumene","authors":"Gustavo D. Rosales ,&nbsp;Alexander C. Resentera ,&nbsp;Gretel J. Fino ,&nbsp;Eliana G. Pinna ,&nbsp;Mario H. Rodriguez","doi":"10.1016/j.hydromet.2024.106336","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106336","url":null,"abstract":"<div><p>Numerous Li extraction methods from minerals and e-waste have been reported in the literature. Among them, direct fluorination processes appear to be a viable alternative due to their high lithium extraction efficiencies (&gt;90%) as LiF. However, a drawback is the low water solubility of LiF, which requires acids for its separation and to obtain other commercial lithium salts. An interesting alternative for dissolving salts with low solubility is through the formation of coordination complexes. In this case, aluminum forms highly stable soluble complexes with the F⁻ anion, such as AlF²⁺, AlF₂⁺, AlF₃, AlF₄⁻, AlF₅²⁻, AlF₆³⁻.</p><p>This study proposes an acid-free LiF dissolution methodology using aluminum sulfate as a leaching agent. The LiF dissolution was modeled and optimized using Response Surface Methodology (RSM). The investigated operating parameters for LiF dissolution were the solid/liquid ratio (A), reaction temperature (B), and leaching time (C). Thus, a predictive mathematical model was successfully optimized (R² = 0.9445). The results indicated that the S/L ratio negatively influences the dissolution of LiF, while temperature and time have a positive effect. The LiF dissolutions of 90 ± 3% were achieved with a leaching time of 31 min, a S/L ratio of 20 g/mL, and a temperature of 45 °C.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"227 ","pages":"Article 106336"},"PeriodicalIF":4.7,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141095572","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":"Complete gold extraction and recovery from double refractory gold ores by thiourea after bio-oxidation","authors":"Keiko Sasaki ,&nbsp;Ikumi Suyama ,&nbsp;Ryusei Takimoto ,&nbsp;Kojo Twum Konadu ,&nbsp;Hirofumi Ichinose ,&nbsp;Jacques Eksteen","doi":"10.1016/j.hydromet.2024.106330","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106330","url":null,"abstract":"<div><p>Cyanidation, a conventional process to extract gold from gold ores, has been used for over 130 years in industrial mining because of the high efficiency and rate of formation of Au(CN)₂⁻ and the high recovery efficiency by adsorption of Au(CN)₂⁻ on activated carbon. However, carbonaceous refractory gold ores are not targeted because Au(CN)₂⁻ is easily adsorbed on carbonaceous matter in the ores, resulting in high recovery loss. In this study, the flotation concentrates of a carbonaceous refractory gold ores was subjected to biooxidation at 45 °C using a mixed culture containing iron-oxidizing and sulfur-oxidizing bacteria, followed by gold extraction using thiourea under strongly acidic conditions. The gold extraction efficiency reached ∼100% in 12 h without re-adsorption. Finally, the quantitative recovery of the Au(CS(NH₂)₂)₂⁺ complex was confirmed by adsorption on strongly cationic exchange resin. Biooxidation reduced the amount of Fe-containing metal sulfides, which minimized the decomposition of thiourea, and the Au(CS(NH₂)₂)₂⁺ complex had a low affinity toward carbonaceous matter, different to Au(CN)₂⁻. Since the process described in this study does not require roasting to remove carbonaceous materials in pretreatment and does not use cyanide for gold extraction, it is environmentally friendly and should be considered for practical applications in carbonaceous gold ore-producing mines.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"227 ","pages":"Article 106330"},"PeriodicalIF":4.7,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141068424","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":"Separation and recovery of sulfur from direct leach residue of zinc oxygen pressure leaching by dissolution in n-decane and recrystallization","authors":"Lijie Chen ,&nbsp;Shenghui Wen ,&nbsp;Ao Gong ,&nbsp;Xiaoqiang Yu ,&nbsp;Jiacong Xu ,&nbsp;Qin Yi ,&nbsp;Lei Tian ,&nbsp;Ruixiang Wang ,&nbsp;Zhifeng Xu","doi":"10.1016/j.hydromet.2024.106319","DOIUrl":"https://doi.org/10.1016/j.hydromet.2024.106319","url":null,"abstract":"<div><p>The effective recovery and utilization of elemental sulfur in the direct leach residue (DLR) from zinc oxygen pressure leaching poses a significant challenge. This study analyzes the distribution characteristics of sulfur in DLR and determines its solubility in <em>n</em>-decane at various temperatures. Results indicate a gradual increase in sulfur solubility with temperature, reaching a maximum of 6.84 g/100 mL at 150 °C Utilizing the Apelblat model, a fitting equation of ln<em>X</em> = 88.3–7155.9/<em>T</em> − 12.0ln<em>T</em> is derived. Under conditions of 130 °C, a liquid–solid ratio of 8:1, a reaction time of 3 min, and a stirring speed of 300 rpm, 99.2% of sulfur in the residue can be dissolved in <em>n</em>-decane. Additionally, this separation process naturally enriches other valuable elements in the residue. The cooling rate significantly influences sulfur purity, with elemental sulfur forming high-quality crystals exhibiting a positive octahedral rhombic morphology at a cooling rate of 0.018 °C/s. Finally, the dissolution mechanism of sulfur in <em>n</em>-decane involves sulfur complexation, and the reliability of the sulfur solubility model is verified.</p></div>","PeriodicalId":13193,"journal":{"name":"Hydrometallurgy","volume":"227 ","pages":"Article 106319"},"PeriodicalIF":4.7,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140918116","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}