Minerals
·
2024
·Vol. 14
·期 4
·352
·
IF 2.2
Zujiang Pan,Cuo Jian,Zaihua Peng,Xinzhuang Fu,Rui He,Tong Yue,Wei Sun
The Yulong copper deposit in Tibet is a typical porphyry copper deposit, with about 30 million tons of copper oxide ore in the surface layer. However, more than 40% of the copper resources are in a combination state, resulting in an extraction efficiency of only 50% for copper via the hydrometallurgical process. In this study, the process mineralogy of the combined copper oxide ore was systematically investigated and a calcium fluoride-enhanced leaching process is proposed to increase the leaching efficiency of the combined copper ore. The process mineralogy of the combined copper oxide ore was analyzed using various testing techniques, including chemical analysis, X-ray diffraction, and a process mineralogy parameter testing system (Mineral Liberation Analysis). The results revealed that limonite accounted for 86.12% of the sample, and 63.51% of the copper resource existed in the form of combined copper oxide in limonite. However, it is difficult for the uniformly distributed combined copper oxide in limonite to sufficiently make contact with sulfuric acid, which is the leaching agent, resulting in low copper leaching efficiency. The enhanced leaching behavior of the combined copper oxide ores was also investigated, thereby determining effective and economical enhanced leaching conditions. Under optimal conditions, at a grinding fineness ratio of −0.074 mm (accounting for 85%), liquid-solid ratio of 4:1, sulfuric acid concentration of 50 g/L, temperature of 30 °C, CaF2dosage of 1% of the ore mass, and leaching time of 4 h, the copper leaching efficiency increased to 60.57%, which was 7.34% higher than that of atmospheric pressure leaching. Finally, the enhanced leaching slag was analyzed using an electron probe microanalyzer. It indicated that fluorine ions can erode the combined copper oxide ore and facilitate the diffusion of hydrogen ions inside the limonite, thereby achieving a strengthening effect.
研究领域:
冶金学
·
矿物学
✓ 已验证
DOI
高影响因子
Minerals
·
2023
·Vol. 13
·期 3
·452
·
IF 2.5
Rui Chen,Lin Shi,Haoyong Huang,Jie Yuan
Red mud, which could cause numerous problems to the environment, is a hazardous waste generated from the alumina smelting industry. In general, the storage and harmless utilization of red mud are hard to implement due to its fine particle size and high alkalinity. This study put forward a novel process to separate iron (MgFe2O4) and alumina (Al2O3) in red mud by a magnetization sintering method. The magnesium oxide was added to transform the nonmagnetic Fe2O3into magnetic MgFe2O4to achieve physical separation of iron-bearing minerals, and the alumina-bearing minerals were converted into dissoluble NaAlO2minerals in a one-step reaction. The atmospheric pressure leaching process was adopted in this study for alumina resource recovery. To achieve clean alumina production, the silicate in the leaching solution was removed by adding the slightly soluble CaSO4, and the entire process becomes clean and harmless. The feasibility of the process was verified by thermodynamic analysis, and a series of experiments were performed to detect the optimum MgO/(Fe2O3+ MgO) ratio and the calcining and leaching conditions. The morphological and mineralogical characteristics of modified red mud, leaching red mud, and magnetic separation product were studied by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS). It was observed that under the optimal conditions with MgO/(Fe2O3+ MgO) of 14.89% to recover iron and aluminum, the corresponding recovery rates were 67.54% and 73.01% respectively, and the iron grade was 30.46%. The EDS results showed that the obtained Mg/Fe ratio of the magnetic separation product was 0.4677–0.528, which is slightly different from that of the standard MgFe2O4at 0.5. This new method can promote the development of comprehensive utilization of red mud and iron production.Keywords:red mud;harmless utilization;mineralogical analysis;MgFe2O4;leaching parameter
研究领域:
冶金工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2021
·
IF 5.039
Yuxiao Xue,Jian Pan,Deqing Zhu,Zhengqi Guo,Hongyu Tian,Yue Shi,Shenghu Lu
Iron ores always contain several forms of alumina, which may have different effect on sintering performance. In this paper, sinter pot tests were systematically conducted with various alumina types and contents by means of alumina additives substituting for the corresponding types of alumina, and the relevant action mechanism on sintering performance was clarified by the mineralogy of product sinter. The results show that kaolinite is beneficial to the granulation process rather than other three alumina types. In addition, it contributes to relatively better sintering performance while aluminous goethite ranks the only next, followed by gibbsite and free alumina. Mechanism analysis indicates that kaolinite and aluminous goethite are preferable to achieve relatively lower sinter porosity and higher amount of silico-ferrite of calcium and alumina (SFCA) compared with gibbsite and free alumina. Besides, the former two alumina types are apt to promote the formation of higher strength SFCA such as dendritic and acicular SFCA. Furthermore, much tighter interlocking texture in product sinter is formed as alumina occurs in kaolinite or aluminous goethite. Kaolinite and aluminous goethite are the preferably desirable alumina types for sintering rather than free alumina and gibbsite.
研究领域:
冶金工程
·
材料科学
✓ 已验证
DOI
高影响因子
INFRARED PHYSICS & TECHNOLOGY
·
2024
·
IF 3.1
Tong Zhang,Zhiyuan Zheng,Mingrui Zhang,Shanshan Li,Xiaodi Zheng,Haochong Huang,Junfeng Shen,Zili Zhang,Kunfeng Qiu
The Bayan Obo deposit is the world’s largest polymetallic associated minerals deposit of rare earths, iron and niobium, and the rarity of its physical properties restrict the knowledge and understanding of its laws. Taking the high-grade mixed rare earth concentrate of Bayan Obo as the research object, terahertz time-domain spectroscopy (THz-TDS) has been adopted for the systematic investigation of high-grade rare earth concentrate base on the traditional X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric-differential thermal analysis (TG-DTA). The absorption coefficient and refractive index of high-grade rare earth ores and their associated minerals of fluorite and dolomite, are all investigated by terahertz time-domain spectroscopy. The terahertz spectral response is affected by the type of mineral and its content. The acquired rare earth terahertz spectral data are processed by correlation analysis. Three machine learning algorithms, Partial Least Squares Regression (PLSR), Random forest (RF) and Multilayer Perceptron (MLP), are used to achieve quantitative detection of their concentrations and components with the coefficient of determination R 2 of the absorption coefficient of the optical parameter reaching up to 0.975, 0.992 and 0.984, respectively. This work promotes the growing understanding of terahertz transmission spectroscopy of rare earth-bearing minerals, which can be used to help guide the search for minerals, and to detect, identify as well as quantify them in geology. Terahertz time-domain spectroscopy supplies a new method for study of rare earth resources, and the comprehensive development and utilization of resources in the Bayan Obo deposit.
研究领域:
矿物学
·
光谱学
·
地质学
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2024
·
IF 4.9
Haiping Zhao,Zhiwei Liu,Jingzhi Liu,Xinxing Liang,Xueping Hu,Wenquan Duan,Junsheng Ma,Liqiang Gao,Zifeng Yu,Renman Ruan
This work attempts to clarify the reason for low gold recovery in Carlin-type gold ores flotation by revealing the correlation of interactions between pyrite and dolomite during the oxidation process with flotation performance. In this paper, the sulfur oxidation rate determined by Ion chromatography (IC) was adopted to evaluate the oxidation degrees of the mixed pyrite and dolomite systems. Flotation tests observed that the difference in the floating rate of pyrite and dolomite gradually decreases with the accumulation of oxidation degrees. The normalized Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) identified the homogenization effect that occurs between pyrite and dolomite surface during the oxidation process can change the affinity of the mineral surface towards the xanthate collector. Focused beam reflectance measurement (FBRM), Particle video microscope (PVM), and Extended Derjaguin–Landau–Verwey–Overbeek (E-DLVO) calculation show that the homogenization effect changes the interaction force between oxidized pyrite and dolomite, and caused the adhesion between minerals, ultimately, deteriorated the separation performance of Carlin-type gold deposits. This study can give a more detailed explanation of the reason for poor selectivity in the Carlin-type gold ores flotation.
研究领域:
矿物学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 21
·5145
·
IF 3.1
Siqi Lv,Yujian Liang,Xuezhen Zhang,Xiaomei Tan,Zuotan Huang,Xuan Guan,Chongmin Liu,Zhihong Tu
Pyrite is one of the most abundant metal sulfide tailings and is susceptible to oxidation, yielding acidic mine drainage (AMD) that poses significant environmental risks. Consequently, the exploration of pyrite surface oxidation and the kinetic influencing factors remains a pivotal research area. Despite the oxidation of pyrite producing a significant amount of sulfate (SO42−), a comprehensive investigation into its influence on the oxidation process is lacking. Leveraging pyrite’s semiconducting nature and the electrochemical intricacies of its surface oxidation, this study employs electrochemical techniques—cyclic voltammetry (CV), Tafel polarization, and electrochemical impedance spectroscopy (EIS)—to assess the effect of SO42⁻ on pyrite surface oxidation. The CV curve shows that SO42−does not change the fundamental surface oxidation mechanism of pyrite, but its redox peak current density decreases with the increase in SO42−, and the surface oxidation rate of pyrite decreases. The possible reason is attributed to SO42−adsorption onto pyrite surfaces, blocking active sites and impeding the oxidation process. Furthermore, Tafel polarization curves indicate an augmentation in polarization resistance with elevated SO42−concentrations, signifying heightened difficulty in pyrite surface reactions. EIS analysis underscores an increase in Weber diffusion resistance with increasing SO42⁻, indicating that the diffusion of Fe3+to the pyrite surface and the diffusion of oxidized products to the solution becomes more difficult. These findings will improve our understanding of the influence of SO42−on pyrite oxidation and have important implications for deepening the understanding of surface oxidation of pyrite in the natural environment.
研究领域:
环境科学
·
电化学
·
矿物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RARE METALS
·
2025
·
IF 11
Pan Jia-Xin,Zhao Long-Sheng,Li Zheng,Feng Zong-Yu,Liu De-Peng,Chen Jun,Huang Xiao-Wei
To achieve selective leaching of ion adsorption rare earth, it is necessary to thoroughly reveal the differences in the adsorption mechanisms of aluminum and rare earth elements. In this study, we investigated the adsorption processes of Dy and Al on the surface of K–homoionic kaolinite using batch experiments and sequential chemical extractions. The results revealed that the adsorption of Dy and Al, as well as the desorption of K, followed the Langmuir model. The maximum ion-exchangeable capacity of Dy was higher (9.39 mmol·kg −1 ) than that of Al (6.30 mmol·kg −1 ). The ion exchange stoichiometry ratios of Dy–K and Al–K derived from the Langmuir model were 2.0 and 2.6. The analysis of X-ray absorption fine structure (XAFS) and density functional theory (DFT) revealed that Dy and Al were adsorbed onto kaolinite as outer-sphere hydrated complexes via hydrogen bonds. Dy was adsorbed as [Dy(H 2 O) 10 ] 3+ , and Al was adsorbed as [Al(OH) 2 (H 2 O) 4 ] + . In particular, the adsorption of Al resulted in protonation of the hydroxyl groups on the surface of the kaolinite. Based on the above insights, the higher ion exchange stoichiometry ratios are attributed to closer adsorption distances (6.04 Å for Dy and 3.69 Å for Al) and lower adsorption energies (− 223.72 kJ·mol −1 for Dy and − 268.33 kJ·mol −1 for Al). The maximum ion-exchangeable capacity is related to the change of the surface electrical properties of kaolinite. The zeta potential was increased to − 7.3 mV as the protonation resulted from aluminum adsorption, while Dy adsorption had a minor effect, maintaining a value of − 17.5 mV. Graphical abstract
研究领域:
矿物学
·
环境科学
·
理论化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Yu Wang,Lkhamsuren Bayarjargal,Maxim Bykov,Elena Bykova,Dominik Spahr,Konstantin Glazyrin,Victor Milman,Bjoern Winkler
We synthesized three carbonates, Cr2[CO3]3, Cr2[C2O5][CO3]2, and Cr2[CO3][O]2, containing Cr3+ by laser heating of chromium oxides in CO2 at pressures between 45 and 55 GPa. All phases were characterized by single-crystal X-ray diffraction and Raman spectroscopy, while density functional theory calculations complemented the experimental results. The structure of Cr2[CO3]3-P63/m contains coplanar groups, and a 4f Wyckoff site is half occupied by Cr3+. Cr2[C2O5][CO3]2-C2/c is characterized by coplanar [CO3]2− and pyro-[C2O5]2− anions and is isostructural to Al2[C2O5][CO3]2. It was obtained only after prolonged laser heating. The oxycarbonate Cr2[CO3][O]2-Pbcn was synthesized at the highest pressure (55 GPa) studied here. In this structure, half of the oxygen atoms coordinate one carbon and two Cr atoms, while the other half coordinate three chromium atoms. The oxidation state of chromium in the carbonates is +3, independent of the oxidation state (+3 or +4) of chromium in the oxide starting material. We observed the transformation of Cr2O3-R3̅c to Cr2O3-Pbcn above 45(2) GPa after laser heating.
研究领域:
矿物学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 17
·4194
·
IF 4.2
Kaiwei Ding,Tingsheng Qiu,Xianhui Qiu,Guanfei Zhao,Qinghao Jiao,Jiangjie Fang,Ruisen Lai,Wenhui Yang
The floatability of fluorite and calcite exhibit similar properties, rendering their flotation separation challenging. Macromolecular polysaccharide reagents containing the polyhydroxyl group have shown broad promising application. The selectivity of polysaccharide is relatively low. In this study, the introduction of Fe3+was employed to enhance the selective adsorption capacity of Pullulan polysaccharide towards fluorite and calcite minerals, thereby achieving effective flotation separation. Furthermore, the mechanism underlying intramolecular interactions was elucidated. The DFT calculation and XPS analysis revealed that the adsorption of Fe3+on the calcite surface was more favorable, leading to the formation of a Ca-O-Fe structure. The MD simulation, XPS analysis, and Zeta potential analysis revealed that the Fe-OH groups on the surface of calcite reacted with the -OH groups in Pullulan and formed bonds, resulting in the formation of a Calcite-Fe-Pullulan structure. This facilitated the attachment of a significant number of Pullulan molecules to the calcite surface. The formation of a hydrophilic layer on the outer surface of calcite by Pullulan, in contrast to the absence of such layer on fluorite’s surface, results in an increased disparity in surface floatability between these two minerals, thereby enhancing the efficiency of flotation separation.
研究领域:
矿物学
·
表面化学
·
分子动力学模拟
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2024
·
IF 7.6
Siyi Pan,Pingxiao Wu,Leiye Sun,Meiqing Chen,Bo Li,Tianming Wang,Zhongbo Shang,Jiangmin Fang,Nengwu Zhu,Zhi Dang
Green rust (GR), as a vital intermediate product during the formation of various iron oxides, exists with organic matters and metals contaminants in natural environments. Understanding the effects of these natural factors on the transformation process of GR into iron oxides and the environmental behaviors of heavy metals and organic matters during process are critical for environmental quality management, but the fundamental identification of the interaction mechanisms between them and GR is still challenging. In this study, the transformation mechanisms of Co-bearing green rust (GR-Co) synthesized by co-precipitation, and the redistribution behaviors of Co(II) in an environment containing oxalic acid (OA) and citric acid (CA) were clarified. The findings indicated that OA promoted the Fe(II) dissolution and the transformation of GR-Co to goethite, while CA decreased the Fe(II) dissolution and the proportion of non-extractable Co. Furthermore, in the presence of CA, the transformation products of GR-Co were ferrihydrite, magnetite, lepidocrocite and goethite instead of only lepidocrocite and goethite. Meanwhile, CA prohibited ferrihydrite from transforming into more highly crystalline iron minerals. The finding of this study improves the understanding of the interaction mechanisms between GR-Co and organic matter, and the environmental geochemical behaviors of Co and organic carbon during the transformation processes in nature.
研究领域:
环境科学
·
矿物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Hongmei Tang,Meiqing Chen,Pingxiao Wu,Yihao Li,Tianming Wang,Jiayan Wu,Leiye Sun,Zhongbo Shang
Schwertmannite (Sch) is considered as an effective remover of Chromium (Cr) due to its strong affinity for toxic Cr species. Since the instability of Sch, the environmental fate of Cr deserves attention during the transformation of Sch into a more stable crystalline phase. The ubiquitous manganese(II) (Mn(II)) probably affects the transformation of Sch and thus the environmental fate of Cr. Therefore, this study investigated the impact of Mn(II) on the transformation of Cr-absorbed Sch (Cr-Sch) and the associated behavior of SO 4 2− and Cr. We revealed that the transformation products of Cr-Sch at pH 3.0 and 7.0 were goethite and Sch, respectively. The presence of Mn(II) weakened the crystallinity of the transformation products, and the trend was positively correlated with the concentration of Mn(II). However, Mn(II) changed the transformation products of Cr-Sch from hematite to goethite at pH 10.0. Mn(II) replaced Fe(III) in the mineral structures or formed Mn-O complexes with surface hydroxyl groups (-OH), thereby affecting the transformation pathways of Sch. The presence of Mn(II) enhanced the immobilization of Cr on minerals at pH 3.0 and 7.0. Sch is likely to provide an channel for electron transfer between Mn(II) and Cr(VI), which promotes the reduction of Cr(VI). Meanwhile, Mn(Ⅱ) induced more -OH production on the surface of secondary minerals, which played an important role in increasing the Cr fixation. In addition, part of the Mn(Ⅱ) was oxidized to Mn(Ⅲ)/Mn(Ⅳ) at pH 3.0 and pH 7.0. This study helps to predict the role of Mn(II) in the transformations of Cr-Sch in environments and design remediation strategies for Cr contamination.
研究领域:
环境科学
·
矿物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Central South University
·
2024
·Vol. 31
·期 2
·317-329
·
IF 3.7
Yang Hui-fang,Sha Ao-yang,He Zheng-yan,Wu Ming,Qu Jun,Wu Chen-jie,Xu Zhi-gao,Chi Ru-an
In order to solve landslides and slow infiltration rate in in-situ leaching process of weathered crust elution-deposited rare earth ore (WCE-DREO), the swelling inhibition performance and mechanism of polyethyleneimine (PEI) on montmorillonite (MMT) and WCE-DREO were investigated. The swelling inhibition effect on MMT and WCE-DREO increased gradually with increasing concentration of PEI. The leaching efficiency of rare earths was increased from 93.94% to 95.24% by the compound leaching agent consisting of 0.4% PEI and 2% ammonium sulfate compared to 2% ammonium sulfate alone, and the leaching time was reduced by about 33%. PEI can produce a large amount of —NH 3 + by hydrolysis, which can neutralize the negative charge on the interlamination and surfaces of clay minerals, reduce the electrostatic repulsion, and weaken the hydration and swelling of clay minerals. A polymeric film was formed on the clay particles by PEI coating, which changed the hydrophilicity of the particle surface, reduced water intrusion. Small particles were agglomerated by the wrapping and linking effects of long-chain PEI, thus increasing the particle size and facilitating the percolation of leaching agent. PEI skeleton also could embed in the clay interlayer and extrude the interlayer water, which inhibits the swelling of clay minerals.
研究领域:
土壤学
·
矿物学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）