María Guadalupe Castro González, María Pilar Prieto Martínez, Antonio Martínez Cortizas
Phosphorus is a key element for identifying past human activity. Recently, phosphorus analyses have been extended to archaeological objects, aiming at distinguishing how depositional contexts contribute to its enrichment. In archaeological pottery, phosphorus might depend on several manufacturing and postdepositional processes (i.e., addition of organic temper, pigments, diagenetic incorporation). We analyzed by XRD, XRF, and mid-infrared (FTIR-ATR) spectroscopy 178 pots from eight NW Spain archaeological sites. These sites encompass different chronologies, contexts, and local geology. The phosphorus content was highly variable (224–27,722 mg kg−1) overall but also between archeological sites (1644 ± 487 to 13,635 ± 6623 mg kg−1) and within archaeological sites (4–36, max/min ratio). No phosphate minerals were identified by XRD nor FTIR-ATR, but correlations between phosphorus content and MIR absorbances showed maxima at 1515 and 980 cm−1, suggesting the presence of two sources: one organic (i.e., phosphorylated aromatic compounds) and another inorganic (i.e., albite and K-feldspar). Phosphorylated aromatics were most likely formed during pottery firing and were preserved due to their high resistance to temperature and oxidation. Meanwhile, albite and K-feldspar are among the P-bearing minerals with higher P concentrations. Our results suggest that P content is related to intentional and non-intentional actions taken in the pottery production process.
磷是确定过去人类活动的关键因素。最近，磷分析已扩展到考古物品，旨在区分沉积环境如何导致磷的富集。在考古陶器中，磷可能取决于几个制造和沉积后过程（即添加有机物、颜料、成岩作用）。我们通过 XRD、XRF 和中红外（FTIR-ATR）光谱分析了来自西班牙西北部八个考古遗址的 178 件陶器。这些遗址的年代、背景和当地地质各不相同。总体而言，磷含量变化很大（224-27,722 毫克/千克-1），但考古遗址之间（1644 ± 487 至 13,635 ± 6623 毫克/千克-1）和考古遗址内部（4-36，最大/最小比）的磷含量变化也很大。XRD 和 FTIR-ATR 均未发现磷酸盐矿物，但磷含量与 MIR 吸光度之间的相关性显示，在 1515 和 980 cm-1 处存在最大值，表明存在两个来源：一个是有机来源（即磷化芳香族化合物），另一个是无机来源（即白云石和 K 长石）。磷酸化芳香族化合物很可能是在陶器烧制过程中形成的，由于其耐高温和抗氧化性而得以保存。同时，白云石和钾长石是含 P 较高的矿物。我们的研究结果表明，P 含量与陶器生产过程中的有意和无意行为有关。
{"title":"The Role of Mineral and Organic Composition on the Phosphorus Content of Prehistoric Pottery (Middle Neolithic to Late Bronze Age) from NW Spain","authors":"María Guadalupe Castro González, María Pilar Prieto Martínez, Antonio Martínez Cortizas","doi":"10.3390/min14090880","DOIUrl":"https://doi.org/10.3390/min14090880","url":null,"abstract":"Phosphorus is a key element for identifying past human activity. Recently, phosphorus analyses have been extended to archaeological objects, aiming at distinguishing how depositional contexts contribute to its enrichment. In archaeological pottery, phosphorus might depend on several manufacturing and postdepositional processes (i.e., addition of organic temper, pigments, diagenetic incorporation). We analyzed by XRD, XRF, and mid-infrared (FTIR-ATR) spectroscopy 178 pots from eight NW Spain archaeological sites. These sites encompass different chronologies, contexts, and local geology. The phosphorus content was highly variable (224–27,722 mg kg−1) overall but also between archeological sites (1644 ± 487 to 13,635 ± 6623 mg kg−1) and within archaeological sites (4–36, max/min ratio). No phosphate minerals were identified by XRD nor FTIR-ATR, but correlations between phosphorus content and MIR absorbances showed maxima at 1515 and 980 cm−1, suggesting the presence of two sources: one organic (i.e., phosphorylated aromatic compounds) and another inorganic (i.e., albite and K-feldspar). Phosphorylated aromatics were most likely formed during pottery firing and were preserved due to their high resistance to temperature and oxidation. Meanwhile, albite and K-feldspar are among the P-bearing minerals with higher P concentrations. Our results suggest that P content is related to intentional and non-intentional actions taken in the pottery production process.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"272 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, column flotation was used to recover a high-grade concentrate from low-grade WO3 ore. Gas dispersion properties, such as superficial gas velocity, gas holdup, bubble size, bubble surface area flux, carrying rate, and bias, were investigated in two phases (gas–liquid) and three phases (gas–liquid–solid) in the column, and their effects on the grade and recovery of WO3. It was confirmed that the gas velocity significantly affected these factors, with the gas holdup, bubble size, bubble surface area flux, and carrying rate tending to increase as the gas velocity increased. The bias increased with an increase in the wash water velocity. The results showed that the grade and recovery of WO3 could be controlled within a specific range of operating conditions of bias (0.27–0.48 cm/s) and carrying rate (10.53–18.83 g/min/cm2). Correlation plots of grade/recovery versus bias and carrying rate revealed that the optimal separation achievable for a given WO3 concentrate in a flotation column was a 72.16% grade with a 78.3% recovery, satisfying the metallurgical requirement of more than 50% for WO3.
{"title":"Effect of Gas Dispersion Properties and Bias in Scheelite Column Flotation","authors":"HyunSoo Kim, Chul-Hyun Park","doi":"10.3390/min14090881","DOIUrl":"https://doi.org/10.3390/min14090881","url":null,"abstract":"In this study, column flotation was used to recover a high-grade concentrate from low-grade WO3 ore. Gas dispersion properties, such as superficial gas velocity, gas holdup, bubble size, bubble surface area flux, carrying rate, and bias, were investigated in two phases (gas–liquid) and three phases (gas–liquid–solid) in the column, and their effects on the grade and recovery of WO3. It was confirmed that the gas velocity significantly affected these factors, with the gas holdup, bubble size, bubble surface area flux, and carrying rate tending to increase as the gas velocity increased. The bias increased with an increase in the wash water velocity. The results showed that the grade and recovery of WO3 could be controlled within a specific range of operating conditions of bias (0.27–0.48 cm/s) and carrying rate (10.53–18.83 g/min/cm2). Correlation plots of grade/recovery versus bias and carrying rate revealed that the optimal separation achievable for a given WO3 concentrate in a flotation column was a 72.16% grade with a 78.3% recovery, satisfying the metallurgical requirement of more than 50% for WO3.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"272 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fine particle content significantly affects the in situ leaching of ion-adsorption-type rare earth ores. This study investigated the effect of fine particle content on solution flow and mass transfer in leaching. The results showed that with the increase in fine particle content, the peak concentration and peak time of rare earth increased. When the fine particle content exceeded 20%, all ion-exchangeable-phase rare earth ions could be replaced with a low dosage of the leaching solution. The leachate flow rate exhibited multi-stage variation, influenced by solution permeation, ion exchange, and fluctuations in accumulated liquid height. A mass transfer analysis showed that a higher fine particle content corresponded to a smaller plate height and a larger plate number of theoretical plates. As fine particle content increased, the final rising height of capillary water decreased, with rising rates varying across different stages for the samples. Moreover, an increase in fine particle content from 5% to 20% resulted in a 94% decrease in the samples’ permeability coefficients. A mechanism analysis showed that when the fine particle content was higher, the fine particles were embedded in the gaps between coarse particles, and the ore particles in the sample were arranged continuously, resulting in a lower permeability coefficient. Then, the leaching solution could penetrate uniformly, which was beneficial for reducing leaching blind spots and improving leaching efficiency. However, excessive fine particle content might have detrimental effects. Based on these results and considering actual mining conditions, the optimal fine particle content for rare earth leaching is 20%.
{"title":"Effect of Fine Particle Content on Solution Flow and Mass Transfer of Ion-Adsorption-Type Rare Earth Ores","authors":"Lingbo Zhou, Hongdong Yu, Shijie Kang, Guidong Sun, Yang Deng, Xiaojun Wang, Hanlin Zhao, Jingtao Xu","doi":"10.3390/min14090879","DOIUrl":"https://doi.org/10.3390/min14090879","url":null,"abstract":"Fine particle content significantly affects the in situ leaching of ion-adsorption-type rare earth ores. This study investigated the effect of fine particle content on solution flow and mass transfer in leaching. The results showed that with the increase in fine particle content, the peak concentration and peak time of rare earth increased. When the fine particle content exceeded 20%, all ion-exchangeable-phase rare earth ions could be replaced with a low dosage of the leaching solution. The leachate flow rate exhibited multi-stage variation, influenced by solution permeation, ion exchange, and fluctuations in accumulated liquid height. A mass transfer analysis showed that a higher fine particle content corresponded to a smaller plate height and a larger plate number of theoretical plates. As fine particle content increased, the final rising height of capillary water decreased, with rising rates varying across different stages for the samples. Moreover, an increase in fine particle content from 5% to 20% resulted in a 94% decrease in the samples’ permeability coefficients. A mechanism analysis showed that when the fine particle content was higher, the fine particles were embedded in the gaps between coarse particles, and the ore particles in the sample were arranged continuously, resulting in a lower permeability coefficient. Then, the leaching solution could penetrate uniformly, which was beneficial for reducing leaching blind spots and improving leaching efficiency. However, excessive fine particle content might have detrimental effects. Based on these results and considering actual mining conditions, the optimal fine particle content for rare earth leaching is 20%.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"7 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucas Fonseca Guimarães, Jorge Alberto Soares Tenório, Mentore Vaccari, Denise Crocce Romano Espinosa, Amilton Barbosa Botelho Junior
Recycling processes of lithium-ion batteries used in electric and hybrid vehicles are widely studied today. To perform such recycling routes, it is necessary to know the composition of these batteries and their components. In this work, three pouch and three cylindrical LIBs were discharged, dismantled, and characterized, having their compositions known and quantified. The dismantling was performed using scissors, pliers, and a precision cutter equipment. The organic liquid electrolyte was quantified via mass loss after it evaporated at 60 °C for 24 h. The separators were analyzed using Fourier-transform infrared spectroscopy (FTIR), and the cathode and anode active materials were analyzed using a scanning electronic microscope coupled to an energy-dispersive spectroscope (SEM-EDS), X-ray diffraction (XDR), and energy-dispersive X-ray fluorescence spectrometry (EDXRF). All LIBs were identified by type (NCA, NMC 442, NMC 811, LCO, and two LFP batteries), and a preliminary economic evaluation was conducted to understand their potential economic value (in USD/t). Both results (characterization and preliminary economic evaluation) were considered to discuss the perspective of recycling towards a circular economy for end-of-life LIBs.
如今，电动汽车和混合动力汽车所用锂离子电池的回收工艺已被广泛研究。要执行此类回收路线，就必须了解这些电池及其组件的成分。在这项工作中，对三块袋装和三块圆柱形锂离子电池进行了放电、拆解和表征，并对其成分进行了了解和量化。拆解过程中使用了剪刀、钳子和精密切割设备。使用傅立叶变换红外光谱（FTIR）分析了分离器，并使用扫描电子显微镜耦合能量色散光谱仪（SEM-EDS）、X 射线衍射（XDR）和能量色散 X 射线荧光光谱仪（EDXRF）分析了阴极和阳极活性材料。所有锂电池均按类型（NCA、NMC 442、NMC 811、LCO 和两个 LFP 电池）进行了鉴定，并进行了初步经济评估，以了解其潜在经济价值（以美元/吨计）。考虑到这两项结果（特征描述和初步经济评价），我们从循环经济的角度讨论了报废锂电池的回收问题。
{"title":"Characterization of Lithium-Ion Batteries from Recycling Perspective towards Circular Economy","authors":"Lucas Fonseca Guimarães, Jorge Alberto Soares Tenório, Mentore Vaccari, Denise Crocce Romano Espinosa, Amilton Barbosa Botelho Junior","doi":"10.3390/min14090878","DOIUrl":"https://doi.org/10.3390/min14090878","url":null,"abstract":"Recycling processes of lithium-ion batteries used in electric and hybrid vehicles are widely studied today. To perform such recycling routes, it is necessary to know the composition of these batteries and their components. In this work, three pouch and three cylindrical LIBs were discharged, dismantled, and characterized, having their compositions known and quantified. The dismantling was performed using scissors, pliers, and a precision cutter equipment. The organic liquid electrolyte was quantified via mass loss after it evaporated at 60 °C for 24 h. The separators were analyzed using Fourier-transform infrared spectroscopy (FTIR), and the cathode and anode active materials were analyzed using a scanning electronic microscope coupled to an energy-dispersive spectroscope (SEM-EDS), X-ray diffraction (XDR), and energy-dispersive X-ray fluorescence spectrometry (EDXRF). All LIBs were identified by type (NCA, NMC 442, NMC 811, LCO, and two LFP batteries), and a preliminary economic evaluation was conducted to understand their potential economic value (in USD/t). Both results (characterization and preliminary economic evaluation) were considered to discuss the perspective of recycling towards a circular economy for end-of-life LIBs.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"19 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Highly plastic clays pose significant challenges in engineering projects. Various techniques have been employed to enhance their properties, though many face difficulties related to implementation and environmental impact. This study examines the effect of CO2-induced magnesium carbonate on improving the geotechnical behavior of plastic clay. CO2-induced magnesium carbonate was produced via mineral carbonation and used to improve the behavior of highly plastic natural clay. CO2 gas was injected into a sodium hydroxide solution to produce carbonate ions (CO32−). Magnesium carbonate was precipitated on a laboratory scale by adding magnesium sulfate solution to the carbonate ion solution. Clayey soil samples were obtained from test pits in the Meyghan Plain near Arak, Iran. The clay samples were treated with different percentages of the produced magnesium carbonate. Various parameters of the treated and untreated samples, including index properties, unconfined compressive strength, consolidation behavior, and swelling potential, were studied. It was found that the liquid limit and plasticity index of the treated clay decreased as the magnesium carbonate content increased. The soil classification changed from high plastic clay (CH) to low plastic silt (ML) with the addition of 15% magnesium carbonate to the highly plastic clay. The unconfined compressive strength of the treated clay increased. Additionally, the consolidation behavior and swelling index of the treated clay improved as the magnesium carbonate content increased. This study confirms that CO2-induced magnesium carbonate is a promising material for improving the behavior of highly plastic clays, offering a sustainable approach to environmental management.
{"title":"Utilizing Magnesium Carbonate Induced by CO2 to Modify the Performance of Plastic Clay","authors":"Hadi Mohamadzadeh Romiani, Hamed Abdeh Keykha, Saeed Chegini, Afshin Asadi, Satoru Kawasaki","doi":"10.3390/min14090876","DOIUrl":"https://doi.org/10.3390/min14090876","url":null,"abstract":"Highly plastic clays pose significant challenges in engineering projects. Various techniques have been employed to enhance their properties, though many face difficulties related to implementation and environmental impact. This study examines the effect of CO2-induced magnesium carbonate on improving the geotechnical behavior of plastic clay. CO2-induced magnesium carbonate was produced via mineral carbonation and used to improve the behavior of highly plastic natural clay. CO2 gas was injected into a sodium hydroxide solution to produce carbonate ions (CO32−). Magnesium carbonate was precipitated on a laboratory scale by adding magnesium sulfate solution to the carbonate ion solution. Clayey soil samples were obtained from test pits in the Meyghan Plain near Arak, Iran. The clay samples were treated with different percentages of the produced magnesium carbonate. Various parameters of the treated and untreated samples, including index properties, unconfined compressive strength, consolidation behavior, and swelling potential, were studied. It was found that the liquid limit and plasticity index of the treated clay decreased as the magnesium carbonate content increased. The soil classification changed from high plastic clay (CH) to low plastic silt (ML) with the addition of 15% magnesium carbonate to the highly plastic clay. The unconfined compressive strength of the treated clay increased. Additionally, the consolidation behavior and swelling index of the treated clay improved as the magnesium carbonate content increased. This study confirms that CO2-induced magnesium carbonate is a promising material for improving the behavior of highly plastic clays, offering a sustainable approach to environmental management.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"59 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Calcretes are indurated terrestrial carbonates that are widespread in arid and semi-arid settings and serve as important archives of present and past environments. Here, we use geochemical tools to explore the nature and origin of calcretes documented from tropical Niue Island in the Southwest Pacific. The study recognizes two types of calcretes that differ in their mineral assemblage, microfabrics, elemental chemistry, and carbon and oxygen isotopes. The calcretes common in the paleo-lagoon soils consist of 90% low-Mg calcite and ~10% highly weathered Mg-Al silicates. These pedogenic calcretes formed in the soil profiles within the vadose zone bear the following distinctions: (i) Fe/Al ratio of 0.75, identical to the ratio in soils (Fe/Al = 0.76 ± 0.5), substantiating the link between the calcretes and soils; (ii) presence of rhizoliths, root voids, micritic nodules, and clasts, which are consistent with a pedogenic calcrete fabric; and (iii) 13C and 18O depletions of −10.6‰ and −5.3‰, respectively, which are compatible with carbon sources from microbial and root respiration, as well as formation in oxygen isotope equilibrium with vadose waters. Unlike the pedogenic calcrete, a rare calcrete from the coastal terrace contains an exceptionally rare hydrotalcite [Mg6Al2(CO3)(OH)16(H2O)4] mineral (65%) coated by microbial films. We contend that the hydrotalcite-rich calcrete was deposited through interaction of dolomite with seawater, similar to the method of producing hydrotalcite in the laboratory. 13C and 18O enrichments of 0.8 to 1.7‰ and −1.0 to −1.6‰, respectively, are in agreement with (i) mixed carbon sources consisting of microbial CO2 degassing, seawater HCO3, and dolomite dissolution, and (ii) oxygen isotope equilibration with seawater-derived fluid.
{"title":"Abiotic and Biotic Processes Controlling Deposition of Calcite and Hydrotalcite Calcretes on Niue Island, Southwest Pacific","authors":"Paul Aharon, Neil E. Whitehead","doi":"10.3390/min14090877","DOIUrl":"https://doi.org/10.3390/min14090877","url":null,"abstract":"Calcretes are indurated terrestrial carbonates that are widespread in arid and semi-arid settings and serve as important archives of present and past environments. Here, we use geochemical tools to explore the nature and origin of calcretes documented from tropical Niue Island in the Southwest Pacific. The study recognizes two types of calcretes that differ in their mineral assemblage, microfabrics, elemental chemistry, and carbon and oxygen isotopes. The calcretes common in the paleo-lagoon soils consist of 90% low-Mg calcite and ~10% highly weathered Mg-Al silicates. These pedogenic calcretes formed in the soil profiles within the vadose zone bear the following distinctions: (i) Fe/Al ratio of 0.75, identical to the ratio in soils (Fe/Al = 0.76 ± 0.5), substantiating the link between the calcretes and soils; (ii) presence of rhizoliths, root voids, micritic nodules, and clasts, which are consistent with a pedogenic calcrete fabric; and (iii) 13C and 18O depletions of −10.6‰ and −5.3‰, respectively, which are compatible with carbon sources from microbial and root respiration, as well as formation in oxygen isotope equilibrium with vadose waters. Unlike the pedogenic calcrete, a rare calcrete from the coastal terrace contains an exceptionally rare hydrotalcite [Mg6Al2(CO3)(OH)16(H2O)4] mineral (65%) coated by microbial films. We contend that the hydrotalcite-rich calcrete was deposited through interaction of dolomite with seawater, similar to the method of producing hydrotalcite in the laboratory. 13C and 18O enrichments of 0.8 to 1.7‰ and −1.0 to −1.6‰, respectively, are in agreement with (i) mixed carbon sources consisting of microbial CO2 degassing, seawater HCO3, and dolomite dissolution, and (ii) oxygen isotope equilibration with seawater-derived fluid.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"54 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haiming Guo, Yanguang Li, Bo Chen, Huishan Zhang, Xiaoyong Yang, Li He, Yongjiu Ma, Yunping Li, Jincheng Luo, Haichao Zhao
The ultramafic rock located on the northern slope of Lüliang Mountain in the northwestern region of North Qaidam Orogen is altered to serpentinite. The occurrence of disseminated chromite within the serpentinite holds significant implications for understanding the petrogenesis of the protolith. This work provides strong evidence of a distinct zonal texture in the chromite found in the ultramafic rock, using petrographic microstructure and electron probe composition analysis. The core of the chromite is characterized by high contents of Cr#, with enrichment in Fe3+# (Fe3+/(Cr + Al + Fe3+)) and depletion in Al2O3 and TiO2. The Cr2O3 content ranges from 51.64% to 53.72%, while the Cr# values range from 0.80 to 0.84. The FeO content varies from 24.9% to 27.8%, while the Fe2O3 content ranges from 5.19% to 8.74%. The Al2O3 content ranges from 6.70% to 9.20%, and the TiO2 content is below the detection limit (<0.1%). Furthermore, the rocks exhibit Mg# values ranging from 0.13 to 0.25 and Fe3+# values ranging from 0.07 to 0.12. The mineral chemistry of the chromite core in the ultramafic rock suggests it to be from an ophiolite. This ophiolite originated from the fore-arc deficit asthenosphere in a supra-subduction zone. The estimated average crystallization temperature and pressure of the chromite are 1306.02 °C and 3.41 GPa, respectively. These values suggest that the chromite formed at a depth of approximately 110 km, which is comparable to that of the asthenosphere. The chromite grains are surrounded by thick rims composed of Cr-rich magnetite characterized by enrichment in Fe3+# contents and depletions in Cr2O3, Al2O3, TiO2, and Cr#. The FeO content ranges from 28.25% to 31.15%, while the Fe2O3 content ranges from 44.94% to 68.92%. The Cr2O3 content ranges from 0.18% to 23.59%, and the Al2O3 and TiO2 contents are below the detection limit (<0.1%). Moreover, the rim of the Cr-rich magnetite exhibits Cr# values ranging from 0.90 to 1.00, Mg# values ranging from 0.01 to 0.06, and Fe3+# values ranging from 0.64 to 1.00, indicating late-stage alteration processes. The LA-ICP-MS zircon U-Pb dating of the ultramafic rock yielded an age of 480.6 ± 2.4 Ma (MSWD = 0.46, n = 18), representing the crystallization age of the ultramafic rock. This evidence suggests that the host rock of chromite is an ultramafic cumulate, which is part of the ophiolite suite. It originated from the fore-arc deficit asthenosphere in a supra-subduction zone during the northward subduction of the North Qaidam Ocean in the Ordovician period. Furthermore, clear evidence of Fe-hydrothermal alteration during the post-uplift-denudation stage is observed.
{"title":"The Genesis of Ultramafic Rock Mass on the Northern Slope of Lüliang Mountain in North Qaidam, China","authors":"Haiming Guo, Yanguang Li, Bo Chen, Huishan Zhang, Xiaoyong Yang, Li He, Yongjiu Ma, Yunping Li, Jincheng Luo, Haichao Zhao","doi":"10.3390/min14090871","DOIUrl":"https://doi.org/10.3390/min14090871","url":null,"abstract":"The ultramafic rock located on the northern slope of Lüliang Mountain in the northwestern region of North Qaidam Orogen is altered to serpentinite. The occurrence of disseminated chromite within the serpentinite holds significant implications for understanding the petrogenesis of the protolith. This work provides strong evidence of a distinct zonal texture in the chromite found in the ultramafic rock, using petrographic microstructure and electron probe composition analysis. The core of the chromite is characterized by high contents of Cr#, with enrichment in Fe3+# (Fe3+/(Cr + Al + Fe3+)) and depletion in Al2O3 and TiO2. The Cr2O3 content ranges from 51.64% to 53.72%, while the Cr# values range from 0.80 to 0.84. The FeO content varies from 24.9% to 27.8%, while the Fe2O3 content ranges from 5.19% to 8.74%. The Al2O3 content ranges from 6.70% to 9.20%, and the TiO2 content is below the detection limit (<0.1%). Furthermore, the rocks exhibit Mg# values ranging from 0.13 to 0.25 and Fe3+# values ranging from 0.07 to 0.12. The mineral chemistry of the chromite core in the ultramafic rock suggests it to be from an ophiolite. This ophiolite originated from the fore-arc deficit asthenosphere in a supra-subduction zone. The estimated average crystallization temperature and pressure of the chromite are 1306.02 °C and 3.41 GPa, respectively. These values suggest that the chromite formed at a depth of approximately 110 km, which is comparable to that of the asthenosphere. The chromite grains are surrounded by thick rims composed of Cr-rich magnetite characterized by enrichment in Fe3+# contents and depletions in Cr2O3, Al2O3, TiO2, and Cr#. The FeO content ranges from 28.25% to 31.15%, while the Fe2O3 content ranges from 44.94% to 68.92%. The Cr2O3 content ranges from 0.18% to 23.59%, and the Al2O3 and TiO2 contents are below the detection limit (<0.1%). Moreover, the rim of the Cr-rich magnetite exhibits Cr# values ranging from 0.90 to 1.00, Mg# values ranging from 0.01 to 0.06, and Fe3+# values ranging from 0.64 to 1.00, indicating late-stage alteration processes. The LA-ICP-MS zircon U-Pb dating of the ultramafic rock yielded an age of 480.6 ± 2.4 Ma (MSWD = 0.46, n = 18), representing the crystallization age of the ultramafic rock. This evidence suggests that the host rock of chromite is an ultramafic cumulate, which is part of the ophiolite suite. It originated from the fore-arc deficit asthenosphere in a supra-subduction zone during the northward subduction of the North Qaidam Ocean in the Ordovician period. Furthermore, clear evidence of Fe-hydrothermal alteration during the post-uplift-denudation stage is observed.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"416 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The surface properties of bastnaesite and parisite are similar to their associated gangue mineral, fluorite, which makes the flotation separation of these two rare earth minerals from fluorite one of the industry’s most significant challenges. This study systematically investigates the inhibitory effects and mechanisms of sodium silicate (SS) on bastnaesite, parisite, and fluorite in an octyl hydroxamic acid (OHA) collector system through flotation experiments, various modern analytical methods, and DFT simulations. The flotation test results indicate that the inhibition effects of SS on the three minerals are in the order: fluorite > parisite > bastnaesite. Detection and analysis results indicate that SS forms hydrophilic complexes with Ca atoms on the surfaces of fluorite and parisite, enhancing surface hydrophilicity and inhibiting OHA adsorption, but its impact on bastnaesite is relatively minor. DFT simulation results show that OHA forms covalent bonds with metal ions on mineral surfaces, favoring five-membered hydroxamic-(O-O)-Ce/Ca complexes, and reacts more strongly with Ce atoms than Ca atoms. SS primarily forms covalent bonds with metal atoms on mineral surfaces via the SiO(OH)3− component, and OHA and SS compete for adsorption on the mineral surfaces. OHA has a stronger affinity for bastnaesite, whereas SS shows the highest affinity for fluorite, followed by parisite, and the weakest affinity for bastnaesite.
韧皮石和副韧皮石的表面性质与它们的伴生煤矸石矿物萤石相似，这使得从萤石中浮选分离这两种稀土矿物成为业界最重大的挑战之一。本研究通过浮选实验、多种现代分析方法和 DFT 模拟，系统研究了硅酸钠（SS）在辛基羟肟酸（OHA）捕收剂体系中对韧皮石、芒硝和萤石的抑制作用及其机理。浮选试验结果表明，SS 对三种矿物的抑制作用依次为：萤石 > 阳起石 > bastnaesite。检测和分析结果表明，SS 与萤石和橄榄石表面的 Ca 原子形成亲水络合物，增强了表面亲水性，抑制了 OHA 的吸附，但对韧皮石的影响相对较小。DFT 模拟结果表明，OHA 与矿物表面的金属离子形成共价键，有利于五元羟肟（O-O）-Ce/Ca 复合物，与 Ce 原子的反应比与 Ca 原子的反应更强烈。SS 主要通过 SiO(OH)3- 成分与矿物表面的金属原子形成共价键，而 OHA 和 SS 则在矿物表面竞争吸附。OHA 对韧皮石的亲和力较强，而 SS 对萤石的亲和力最高，其次是黝帘石，对韧皮石的亲和力最弱。
{"title":"New Insights into the Depressive Mechanism of Sodium Silicate on Bastnaesite, Parisite, and Fluorite: Experimental and DFT Study","authors":"Jieliang Wang, Wenda Lu, Zhao Cao, Xu Wu, Peng Wang, Xiaoping Wang, Wenli Liu","doi":"10.3390/min14090870","DOIUrl":"https://doi.org/10.3390/min14090870","url":null,"abstract":"The surface properties of bastnaesite and parisite are similar to their associated gangue mineral, fluorite, which makes the flotation separation of these two rare earth minerals from fluorite one of the industry’s most significant challenges. This study systematically investigates the inhibitory effects and mechanisms of sodium silicate (SS) on bastnaesite, parisite, and fluorite in an octyl hydroxamic acid (OHA) collector system through flotation experiments, various modern analytical methods, and DFT simulations. The flotation test results indicate that the inhibition effects of SS on the three minerals are in the order: fluorite > parisite > bastnaesite. Detection and analysis results indicate that SS forms hydrophilic complexes with Ca atoms on the surfaces of fluorite and parisite, enhancing surface hydrophilicity and inhibiting OHA adsorption, but its impact on bastnaesite is relatively minor. DFT simulation results show that OHA forms covalent bonds with metal ions on mineral surfaces, favoring five-membered hydroxamic-(O-O)-Ce/Ca complexes, and reacts more strongly with Ce atoms than Ca atoms. SS primarily forms covalent bonds with metal atoms on mineral surfaces via the SiO(OH)3− component, and OHA and SS compete for adsorption on the mineral surfaces. OHA has a stronger affinity for bastnaesite, whereas SS shows the highest affinity for fluorite, followed by parisite, and the weakest affinity for bastnaesite.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"17 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study presents the chemical and mineralogical composition of clay deposits and associated rock types within the Ropp Complex in order to assess the influence of parent lithology on the kaolinization, genesis, and utility of the deposit. Representative kaolin samples from E horizons of the weathering profiles and their bedrocks were collected from six sites in the Ropp Complex. Clay mineralogy was determined via the XRD technique, while a geochemical analysis was conducted using XRF, SEM coupled with EDS, and ICP-MS. The results showed that all kaolins dominantly contain kaolinite with a content of 77%–98% except for the AS1 kaolin with only minor kaolinite (20%) but mainly illite (65%). The notably lower crystallinity of kaolinite (HI value of 0.53–1.1) as well as its markedly small grain size is consistent with the formation of kaolinite from intensive chemical weathering of igneous rocks. The AS1 kaolin was probably formed from hydrothermal alteration in the burial stage due to the heating of groundwater by the late volcanism. Mobile trace elements (Sr, Ba, and Eu) exhibited a depletion trend, while immobile elements (Hf, Ta, Th) showed enrichment. The relatively more zirconium in kaolins implies the formation of low-temperature kaolinization. The notably high kaolinite content, accompanied by reasonable levels of Fe2O3 and TiO2, signifies a medium-grade quality. Furthermore, chondrite-normalized rare earth element (REE) patterns exhibit congruent trends in rocks and kaolin samples, indicating a relative enrichment in light rare earth elements (LREEs) alongside a discernible negative Eu anomaly. The abundant kaolinite and silicon–aluminum composition make the kaolins suitable for refractories, pharmaceutics, cosmetics, and supplementary cementitious material (SCM).
{"title":"Mineralogical Characterization and Geochemical Signatures of Supergene Kaolinitic Clay Deposits: Insight of Ropp Complex Kaolins, Northcentral Nigeria","authors":"Adamu Yunusa, Hanlie Hong, Atif Salim, Tarig Amam, Chen Liu, Yanxiao Xu, Xiaochao Zuo, Zhaohui Li","doi":"10.3390/min14090869","DOIUrl":"https://doi.org/10.3390/min14090869","url":null,"abstract":"This study presents the chemical and mineralogical composition of clay deposits and associated rock types within the Ropp Complex in order to assess the influence of parent lithology on the kaolinization, genesis, and utility of the deposit. Representative kaolin samples from E horizons of the weathering profiles and their bedrocks were collected from six sites in the Ropp Complex. Clay mineralogy was determined via the XRD technique, while a geochemical analysis was conducted using XRF, SEM coupled with EDS, and ICP-MS. The results showed that all kaolins dominantly contain kaolinite with a content of 77%–98% except for the AS1 kaolin with only minor kaolinite (20%) but mainly illite (65%). The notably lower crystallinity of kaolinite (HI value of 0.53–1.1) as well as its markedly small grain size is consistent with the formation of kaolinite from intensive chemical weathering of igneous rocks. The AS1 kaolin was probably formed from hydrothermal alteration in the burial stage due to the heating of groundwater by the late volcanism. Mobile trace elements (Sr, Ba, and Eu) exhibited a depletion trend, while immobile elements (Hf, Ta, Th) showed enrichment. The relatively more zirconium in kaolins implies the formation of low-temperature kaolinization. The notably high kaolinite content, accompanied by reasonable levels of Fe2O3 and TiO2, signifies a medium-grade quality. Furthermore, chondrite-normalized rare earth element (REE) patterns exhibit congruent trends in rocks and kaolin samples, indicating a relative enrichment in light rare earth elements (LREEs) alongside a discernible negative Eu anomaly. The abundant kaolinite and silicon–aluminum composition make the kaolins suitable for refractories, pharmaceutics, cosmetics, and supplementary cementitious material (SCM).","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"127 1 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dong Wu, Yu Yu, Liangbiao Lin, Hongde Chen, Sibing Liu
A special type of sandstone in which carbonate rock fragments (CRFs) dominate the composition developed in the Upper Triassic Xujiahe Formation’s fourth member (Xu4) in the western Sichuan Basin, known as calcareous sandstone. Calcareous sandstones are widely distributed in the western Sichuan and is the main production target of tight sandstone gas in the Sichuan Basin. In this study, thin sections, porosity–permeability testing, scanning electron microscopy, and X-ray diffraction are applied to examine the characteristics and control factors for high-quality reservoirs in the calcareous sandstones, with a view to providing guidance for natural gas exploration and development in calcareous sandstones. The results show that the calcareous sandstone belongs to litharenite, with an average framework grain composition of 30% quartz, 1% feldspar, and 69% rock fragments, while the Xu4 sandstone has a high quartz content (average content of 71%). Primary intergranular pores are the main storage space, and the reservoir quality is quite poor. Under the influence of different parent rock properties of sandstones, there are obvious differences in the composition of framework grains between the calcareous sandstone and the ordinary Xu4 sandstone, which in turn affects the reservoir storage space, diagenesis, and reservoir quality. High-energy depositional conditions, low content of late cements, and the development of fractures are the main controlling factors for the formation of high-quality reservoirs in Xu 4 calcareous sandstones.
四川盆地西部三叠系上统徐家河组第四系（徐4）发育了一种以碳酸盐岩碎屑（CRF）为主的特殊砂岩，被称为钙质砂岩。钙质砂岩广泛分布于四川西部，是四川盆地致密砂岩气的主要产气目标。本研究采用薄片、孔隙度-渗透率测试、扫描电镜和 X 射线衍射等方法，研究了钙质砂岩优质储层的特征和控制因素，以期为钙质砂岩天然气勘探开发提供指导。结果表明，钙质砂岩属于石英岩，其平均框架晶粒成分为 30%石英、1%长石和 69%岩石碎片，而 Xu4 砂岩的石英含量较高（平均含量为 71%）。原生晶间孔隙是主要的储集空间，储层质量较差。受砂岩母岩性质不同的影响，钙质砂岩与普通徐4砂岩的框架颗粒组成存在明显差异，进而影响储层的储集空间、成因和储层质量。高能沉积条件、晚期胶结物含量低、裂缝发育是徐4钙质砂岩形成优质储层的主要控制因素。
{"title":"Characteristics and Control Factors of a High-Quality Deeply Buried Calcareous Sandstone Reservoir, the Fourth Member of the Upper Xujiahe Formation in the Western Sichuan Basin, China","authors":"Dong Wu, Yu Yu, Liangbiao Lin, Hongde Chen, Sibing Liu","doi":"10.3390/min14090872","DOIUrl":"https://doi.org/10.3390/min14090872","url":null,"abstract":"A special type of sandstone in which carbonate rock fragments (CRFs) dominate the composition developed in the Upper Triassic Xujiahe Formation’s fourth member (Xu4) in the western Sichuan Basin, known as calcareous sandstone. Calcareous sandstones are widely distributed in the western Sichuan and is the main production target of tight sandstone gas in the Sichuan Basin. In this study, thin sections, porosity–permeability testing, scanning electron microscopy, and X-ray diffraction are applied to examine the characteristics and control factors for high-quality reservoirs in the calcareous sandstones, with a view to providing guidance for natural gas exploration and development in calcareous sandstones. The results show that the calcareous sandstone belongs to litharenite, with an average framework grain composition of 30% quartz, 1% feldspar, and 69% rock fragments, while the Xu4 sandstone has a high quartz content (average content of 71%). Primary intergranular pores are the main storage space, and the reservoir quality is quite poor. Under the influence of different parent rock properties of sandstones, there are obvious differences in the composition of framework grains between the calcareous sandstone and the ordinary Xu4 sandstone, which in turn affects the reservoir storage space, diagenesis, and reservoir quality. High-energy depositional conditions, low content of late cements, and the development of fractures are the main controlling factors for the formation of high-quality reservoirs in Xu 4 calcareous sandstones.","PeriodicalId":18601,"journal":{"name":"Minerals","volume":"16 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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