Hydrometallurgy最新文献_第9页

Dissolution of scheelite under soft acidic conditions via the formation of polyoxotungstate: kinetics and mechanism supported by small-angle X-ray scattering (SAXS) to identify and quantify H3PW12O40 软酸性条件下白钨矿溶解形成多钨氧酸盐：小角x射线散射（SAXS）鉴定和量化H3PW12O40的动力学和机理

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-20 DOI: 10.1016/j.hydromet.2025.106538

Valentin Legrand, Stéphanie Szenknect, Olivier Diat, Luc Girard, Pierre Bauduin

The decomposition of scheelite in a synergistic H₂SO₄-H₃PO₄ mixture is an effective method for extracting tungsten from mining concentrates. The driving force behind the dissolution of scheelite in the H₂SO₄-H₃PO₄ mixture is the formation of a soluble Keggin-type polyoxotungstate, H₃PW₁₂O₄₀, which prevents the formation of very low solubility tungstic acid. In this work, a multiparametric study of scheelite dissolution kinetics was carried out in a synergistic acid mixture. In particular, the independent contributions of temperature, acid concentration, and W:P molar ratio on scheelite dissolution kinetics and H₃PW₁₂O₄₀ formation yield were evaluated. To this end, a method based on the use of small-angle X-ray scattering (SAXS) was developed to identify and quantify H₃PW₁₂O₄₀ under different operating conditions. The results provide a better understanding of the stability range of H₃PW₁₂O₄₀ in terms of H₂SO₄ concentration and stoichiometric W:P ratio. These findings led to the selection of optimized, soft-leaching conditions that ensure rapid dissolution of scheelite while avoiding surface passivation by the precipitation of secondary phases. A comparison with speciation calculations using thermodynamic data reported in the literature reveals an absence of a self-consistent thermodynamic dataset. Thus, measuring the concentration of H₃PW₁₂O₄₀ in the leachate was necessary to optimize the dissolution conditions. From this perpective, SAXS appears to be a suitable quantitative method.

在H2SO4-H3PO4协同混合物中分解白钨矿是一种有效的从选矿精矿中提取钨的方法。白钨矿在H2SO4-H3PO4混合物中溶解的驱动力是可溶性keggin型多钨氧酸盐H3PW12O40的形成，阻止了极低溶解度钨酸的形成。本文对白钨矿在协同酸混合物中的溶解动力学进行了多参数研究。研究了温度、酸浓度和W:P摩尔比对白钨矿溶解动力学和H3PW12O40产率的独立影响。为此，开发了一种基于小角度x射线散射（SAXS）的方法来识别和量化不同操作条件下的H3PW12O40。从H2SO4浓度和化学计量W:P比两个方面对H3PW12O40的稳定性范围有了更好的理解。这些发现有助于选择优化的软浸条件，以确保白钨矿的快速溶解，同时避免二次相的沉淀导致表面钝化。与文献中报道的使用热力学数据的物种形成计算的比较揭示了缺乏自一致的热力学数据集。因此，有必要测量渗滤液中H3PW12O40的浓度，以优化其溶解条件。从这个角度来看，SAXS似乎是一种合适的定量方法。

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引用次数: 0

Synthesis of coal-based activated carbon via one-step activation and its adsorption and stripping performance for gold thiosulfate complexes 一步活化煤基活性炭的合成及其对硫代硫酸金配合物的吸附和剥离性能

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-16 DOI: 10.1016/j.hydromet.2025.106534

Qiang Wang , Tong Liu , Ying Li , Yanhe Nie

The challenges associated with recovering gold from leachates restrict the wide applicability of thiosulfate systems. This study developed a facile one-step activation strategy for synthesizing coal-based activated carbon from low-cost, accessible bituminous coal precursors; the activated carbon was subsequently used to adsorb gold from thiosulfate solutions. The optimal conditions for synthesizing coal-based activated carbon were investigated, along with the effects of pH, temperature, and initial gold concentration on [Au(S₂O₃)₂]³⁻ adsorption by the coal-based activated carbon. The structural and surface properties of the adsorbent were analyzed before and after gold adsorption, which revealed that the initially smooth surface morphology of raw coal became porous after activation and that the surface was loaded with SCN groups. The adsorption process followed pseudo-second-order kinetics and was described using the Freundlich model. The adsorption of [Au(S₂O₃)₂]³⁻ on the coal-based activated carbon was a fast endothermic process. The adsorption equilibrium was attained within 60 min, at a gold concentration of 10 mg/L. The maximum adsorption capacity of gold on the coal-based activated carbon was 3.29 mg/g, at a gold concentration of 80 mg/L at 45 °C. During the gold adsorption, ligand exchange occurred between the [Au(S₂O₃)₂]³⁻ ions in the solution and the SCN groups on the coal-based activated-carbon surface, ultimately facilitating the adsorption of Au(I) in the solution on the activated-carbon surface. Moreover, the [Au(S₂O₃)₂]³⁻-loaded coal-based activated carbon could be effectively eluted by thiosulfate. Hence, this study provides theoretical guidance and a practical basis for the adsorption of gold from thiosulfate leachates using coal-based activated carbon while facilitating clean, high-value utilization of coal resources.

从渗滤液中回收金的挑战限制了硫代硫酸盐系统的广泛适用性。本研究开发了一种简单的一步活化策略，用于从低成本，可获得的烟煤前体合成煤基活性炭；随后用活性炭吸附硫代硫酸盐溶液中的金。研究了煤基活性炭的最佳合成条件，考察了pH、温度和初始金浓度对煤基活性炭吸附[Au(S2O3)2]3−的影响。对吸附金前后吸附剂的结构和表面性能进行了分析，发现原煤表面由最初光滑的表面形貌在活化后变得多孔，表面加载了SCN基团。吸附过程遵循准二级动力学，并采用Freundlich模型进行描述。煤基活性炭对[Au(S2O3)2]3−的吸附是一个快速吸热过程。当金浓度为10 mg/L时，吸附在60 min内达到平衡。在45℃条件下，当金浓度为80 mg/L时，煤基活性炭对金的最大吸附量为3.29 mg/g。在金吸附过程中，溶液中的[Au(S2O3)2]3−离子与煤基活性炭表面的SCN基团之间发生配体交换，最终促进了溶液中Au(I)在活性炭表面的吸附。此外，硫代硫酸盐可以有效地洗脱负载[Au(S2O3)2]3−的煤基活性炭。因此，本研究为煤基活性炭吸附硫代硫酸盐浸出液中的金，促进煤炭资源的清洁、高价值利用提供了理论指导和实践依据。

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引用次数: 0

On the mechanism of the dissolution of gypsum (calcium sulfate dihydrate) 石膏（二水硫酸钙）溶解机理研究

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-14 DOI: 10.1016/j.hydromet.2025.106535

Frank K. Crundwell

The dissolution of minerals is central to many fields of research interest, including hydrometallurgy, materials science, and geochemistry. The successful development of a comprehensive understanding of the mechanism of dissolution will have an impact on these fields. The challenge for the dissolution of gypsum is that rate of dissolution is proportional to the molar concentration of the dissolved salt, yet the solubility product is proportional to the square of the molar concentration of dissolved salt. Deriving an expression that is consistent with both the kinetics and thermodynamics has vexed researchers for decades. Furthermore, the zeta potential of gypsum shows no clear dependence on pH. In this paper, we show that the experimental data for the kinetics of dissolution, the thermodynamics describing the solubility product, and the zeta potential describing the surface charge are reconciled by accounting for the surface charge using the surface vacancy model of dissolution, and in doing so provide insight into the elementary steps involved in the dissolution of gypsum.

矿物的溶解是许多研究领域的核心，包括湿法冶金、材料科学和地球化学。对溶解机理的全面认识的成功发展将对这些领域产生影响。石膏溶解的挑战在于溶解速率与溶解盐的摩尔浓度成正比，而溶解度积与溶解盐的摩尔浓度的平方成正比。推导一个既符合动力学又符合热力学的表达式已经困扰了研究人员几十年。此外，石膏的zeta电位对ph值没有明显的依赖性。在本文中，我们表明，溶解动力学的实验数据，描述溶解度积的热力学数据，以及描述表面电荷的zeta电位，通过使用溶解的表面空位模型来计算表面电荷，是一致的，这样做提供了对石膏溶解所涉及的基本步骤的见解。

引用次数: 0

Separation of thorium using new solvent extractant derived from recycling discarded plastic bottles 利用回收废旧塑料瓶提取的新型溶剂萃取剂分离钍

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-12 DOI: 10.1016/j.hydromet.2025.106533

Ahmed Orabi , Hend Salem , Nagwa Falila , Doaa Ismaiel , Magd Badr

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, T = 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.

由于塑料瓶废弃物的不可生物降解性，本工作提供了一种回收方法，将其转化为一种有价值的高效萃取剂，用于从废矿石中分离钍。利用甘油和二甘醇的混合物对塑料瓶废弃物进行糖酵解，然后利用天然脂肪酸亚麻酸进行酯化，成功合成了一种新的有前途的萃取剂（Rec-UPEST）。进行了一些表征，如FTIR光谱，1H NMR分析和MS分析，以确保其制备得当。制作材料(Rec-UPEST)溶解在CHCl3可以有效提取Th (IV)的最大装载量1.08 g L−1 15分钟,有机水比 = 1:1,T = 298 K, pH值 = 2。红外数据证实萃取剂是通过乙二醇和酯氧原子与钍键合而实现萃取的。斜率分析技术推断Rec-UPEST已经能够以2:1 （Rec-UPEST: Th）的摩尔比提取配合物Th。如所得的McCabe-Thiele图所示，可以通过两个阶段成功地提取和剥离Th。热力学计算表明，Rec-UPEST /Th萃取是一个放热过程。以2 mol L−1 HNO3为溶剂，实现了Th（99.8 %）的溶出。为编制本研究利用的矿化微花岗岩脉废渣中回收Th的所有步骤，建立了建议的流程图。

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引用次数: 0

Modelling the leaching behaviour and particle-size distribution dynamics of poly-disperse particulate solids in a batch reactor 间歇式反应器中多分散颗粒固体的浸出行为和粒径分布动力学模拟

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-08 DOI: 10.1016/j.hydromet.2025.106532

Pavel Raschman, Ľuboš Popovič, Maryna Kyslytsyna, Gabriel Sučik

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.

结合颗粒尺寸分布（PSD）和收缩颗粒模型（SPM），提出了多分散颗粒固体浸出的物质平衡模型。将该模型应用于用稀盐酸溶液浸出天然粗菱镁矿（CNM）。采用宽PSD的CNM样品，根据实测数据确定了表观反应阶数（0.31）和活化能（51.5 kJ mol−1），并建立了模拟模型。随后，采用化学和相组成相同但PSD不同的CNM样品，实验研究了转化率和PSD随浸出时间的变化情况，并验证了模拟模型。实验结果与模拟结果的比较表明：(a)本文方法得到的动力学参数值表征了液固界面上的本征化学反应，与PSD无关；(b)所提出的模型可以预测多分散颗粒固体在间歇反应器中浸出过程中转化程度和PSD的变化。

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引用次数: 0

Choline chloride-lactic acid-ascorbic acid (ChCl-LA-AA) based green deep eutectic solvent for leaching LiMn2O4 cathode material of spent Li-ion batteries 氯化胆碱-乳酸-抗坏血酸（ChCl-LA-AA）基绿色深共晶溶剂浸出废锂离子电池正极材料LiMn2O4

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-07 DOI: 10.1016/j.hydromet.2025.106529

Jasreen Kaur Jasmel Singh , Masud Rana , Md Ishtiaq Hossain Khan , Young Tae Jo, Jeong-Hun Park

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.

锂锰氧化物（LMO）作为锂离子电池（LIBs）正极材料的应用越来越多，因为它具有可负担性、安全性、无毒性和高能量存储能力。尽管它在电动汽车（ev）和便携式设备中的应用正在激增，但从这类废旧电池中回收有价值金属的研究仍然有限。因此，本研究研究了在各种还原剂如抗坏血酸（AA）、葡萄糖和甲酸（FA）的存在下，使用氯化胆碱和乳酸（ChCl-LA）深度共晶溶剂（DES）从废LiMn2O4正极材料中回收锂（Li）和锰（Mn）。利用ICP-OES、XPS、SEM-EDS和XRD分析了废阴极LiMn2O4材料、固体残渣和浸出液的组成。结果表明，在90℃、1 h、料液比20 g/L、ChCl-LA-AA浓度为1:2:1的条件下，Li和Mn金属的浸出效率均达到100%左右。XRD分析结果表明，葡萄糖和FA浸出的固体残渣中存在少量的氧化锰峰，而AA处理后没有出现LiMn2O4峰，证实了金属元素的有效提取。同时，SEM-EDS分析表明，原始LiMn2O4材料具有团聚的纳米颗粒，而固体残留物的孔隙率增加，Mn含量降低（葡萄糖为26.1% wt%， FA为23.9%）。AA浸出后得到的固体渣碳含量显著增加（82.1%），Mn含量显著降低（1.42%）。XPS光谱进一步证实锰（III）或锰（IV）氧化态还原为锰（II）态，Mn和Li几乎完全浸出。最后，提出了从废LiMn2O4中浸出Mn和Li的详细机理。本研究采用的回收工艺是可行的，具有广阔的应用前景。

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引用次数: 0

Arsenic precipitation and bioscorodite crystallization from acidic metallurgical wastewater under different bioreactor schemes: In-silico performance analysis 不同生物反应器方案下酸性冶金废水中的砷沉淀和生物云母结晶：硅性能分析

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-04 DOI: 10.1016/j.hydromet.2025.106531

Evelyn Gaxiola-Muñiz , Ricardo Aguilar-López , Sergio A. Medina-Moreno , Edgar N. Tec-Caamal

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 < R² < 0.99 for all variables with p-values <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.

从水中去除砷仍然是一个需要克服的挑战，而生物诱导形成铁球石为处理冶金工业含砷废水提供了一种有效的方法。本文提出了一个基于模型的动态分析的整体生物云母过程在不同的生物反应器方案。为此，对修正模型进行了实验验证，得到0.87 <；R2 & lt;p值为<；0.001的所有变量均为0.99。验证后的模型能够充分预测各变量的动态，并通过实验观察进行了验证。随后，通过模拟研究了间歇、补料间歇、间歇/连续组合、单级和多级连续生物反应器，测试了影响砷去除能力的操作变量，如接种量、离子浓度、稀释率和播种。然后建立了一个比较基础，以确定生物反应器设置，以提高砷作为生物污泥的固定化。单级和梯级生物反应器具有较高的砷沉淀率（高达3.2 g L−1 d−1），晶体尺寸约为~ 150 μm。结果表明，3个串联反应器可在高进料浓度（6.2 g L−1）下沉淀87%的砷，较高的串联反应器数量可能会提高转化率，但不利于系统的实用性和可行性。间歇式/连续式组合方案可获得大尺寸晶体，最高可达225 μm。这些发现强调了基于模型设计的生物蛭石结晶过程的有效性，为工业废水中的砷去除提供了一种有前途的可扩展解决方案。

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引用次数: 0

Precipitation of rare earth phosphates through apatite leach as by-product of nitrophos acid from unconventional phosphate deposit of carbonatite, Malakand, Pakistan 巴基斯坦马拉坎德碳酸盐岩非常规磷矿硝磷副产物磷灰石浸出沉淀稀土磷酸盐

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-03 DOI: 10.1016/j.hydromet.2025.106530

Farva Arshad , Munirah Atique Khan , Attiqa Nasir , Muhammad Haider Ali , Lubna Basit , Muhammad Nasir Siddique , Muhammad Nadeem

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 <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.

采用破碎、磨矿、重选、磁选等选矿方法对Sellai Patti （Malakand, Pakistan）火成岩碳酸盐岩磷灰石矿石进行了选矿。用65%的硝酸（S/L 0.42, 65℃，700 rpm）浸出精矿[Ca5(PO4)3, F] （30% P2O5, 0.7% REEs）。该渗滤液（稀土2.78 g/L, P2O5 154 g/L）稀土回收率为92%。用两种不同的方法在33%的氨溶液中进行了稀土元素的沉淀。直接沉淀法（DPP）在pH为0.2 ~ 0.5的条件下产生稀土析出物（34%），随后进行热洗。沉淀后的滤液中稀土含量为0.2 g/L， P2O5含量为97 g/L，钙含量为102 g/L。在硝基磷沉淀过程（NPP）中，通过去除四水合硝酸钙（CNTH）形式的溶解钙，在−20°C冻结渗滤液，观察到稀土的预浓度从2.8 g/L到4.1 g/L。在pH为1.7的条件下得到9%的稀土析出物，然后在65%的硝酸（S/L 1:10）中再溶解，用过量50%的草酸过夜再结晶，稀土浓度提高到30%。硝基磷肥的前体硝基磷酸（NP酸）残留的稀土含量仅为1mg /L， P2O5含量为135g /L，钙含量高达40g /L。本研究提出了一种可持续和高效的方法，通过创新和显著有效的DPP提取稀土。

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引用次数: 0

Leaching kinetics of molybdenite with layered structure and hydrophobic properties in the H2SO4-H2O2-H2O system at atmospheric pressure 层状疏水性辉钼矿在常压H2SO4-H2O2-H2O体系中的浸出动力学

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-07-03 DOI: 10.1016/j.hydromet.2025.106527

Zhiyuan Chen , Zihui Jiang , Qiu Hu , Jiangtao Li

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:

1 - \sqrt{1 - α} = k_{r} t = 7.73 \times 10^{3} r_{0}^{- 1} C_{H 2 SO 4}^{0.063} C_{H 2 O 2}^{0.959} e^{- \frac{59706}{RT}} t

以往对辉钼矿浸出动力学的研究主要基于球形矿物颗粒收缩岩心模型的处理数据。辉钼矿颗粒呈薄板状和层状结构。在本研究中，采用圆形粒子模型推导了动力学方程。经计算，未经机械活化和经过机械活化处理的辉钼矿浸出反应的表观活化能分别为55.3 kJ/mol和49.5 kJ/mol。辉钼矿的层状结构使其矿物颗粒在球磨过程中难以研磨。但该过程在一定程度上提高了矿物的活性点，有利于浸出反应的进行。确定浸出反应的限速步骤为化学反应步骤。其中，H2SO4和H2O2的反应阶数分别为0.063和0.959。值得注意的是，H2O2浓度的变化对浸出效果影响显著，而H2SO4浓度的变化对浸出效果的影响相对较小。辉钼矿具有较强的疏水性。表面活性剂的加入改善了反应环境，提高了浸出效果。浸出动力学表达式定义为：1−1−α=krt=7.73×103r0−1CH2SO40.063CH2O20.959e−59706RTt

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引用次数: 0

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 托托尔矿床弱放射性矿石浸出过程中氢气形成的研究：矿石还原性的地球放射化学性质

IF 4.8 2区材料科学 Q1 METALLURGY & METALLURGICAL ENGINEERING

Hydrometallurgy

Pub Date : 2025-06-26 DOI: 10.1016/j.hydromet.2025.106523

Vladimir I. Kuzmin, Dmitrii V. Kuzmin, Oleg A. Epov, Timur Yu. Ivanenko

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.

对俄罗斯托托矿床弱放射性稀有金属矿石进行了直接碱浸试验。研究发现，在各种伴合矿物成分存在的情况下，用氢氧化钠溶液浸出独居石的过程伴随着大量氢气的释放，并形成稳定的泡沫填充反应器，阻止了有害气体的消除。所发现的现象是独特的，因为即使在低温（40-50°C）和在碱性和酸性环境（氢氟酸溶液）中浸出矿石时，氢的释放速度也很高。假定矿石的高还原潜力与长期放射化学照射期间矿物成分的脱氧（除氧）有关。使用固态核磁共振进行的初步研究证实了这一假设。在矿石样品中发现了大量的氢化物离子，氢化物离子是氧化铝和磷酸盐稳定混合簇化合物的一部分。假设在此过程中形成的泡沫具有高稳定性是由于疏水纸浆颗粒（包括未分解的黄铁矿）形成了结构和机械屏障。通过在纸浆中添加阴离子表面活性剂（硬脂酸钠）来消除不希望的泡沫，这确保了从气泡表面去除疏水颗粒。

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