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Economic heavy minerals (EHMs) in the Quaternary Stream Sediments of the Wadi Ibib were characterized mineralogically and chemically via optical microscopy, grain size distribution analysis, heavy liquid separation, X-ray diffraction (XRD), energy-dispersive X-ray fluorescence (EDXRF), and scanning electron microscopy (SEM). Information gathered from characterization studies confirmed that the heavy mineral content (specific gravity of more than 2.89) in the Ibib samples ranged between 8.18 and 17.52% by mass with an average of about 12.56% by mass. EDXRF data analyses also manifested that the content of ilmenite in the Ibib sample reached 0.2%, zircon 0.08%, rutile 0.07%, leucoxene 0.06%, almandine garnet 0.022%, cassiterite 0.007%, xenotime 0.006%, monazite 0.0008%, and magnetite was about 0.29% with high proportion of heavy silicates. With regard to raising the grade of the EHMs, heavy mineral concentrate was obtained through a rougher step on Wilfley Shaking Table No. 13, and then it was followed by two scavenging steps for the highest recovery obtained. The gravimetric concentration steps succeeded in raising the heavy mineral assay from 12.17% to 53.41% with a recovery of 80.42% in a yield of 20.38%. Finally, magnetic separation operations were conducted via low- and high-intensity magnetic separators at different intensities in an attempt to separate and obtain clean concentrates of EHMs that were ready for use in various modern technology industries. [ABSTRACT FROM AUTHOR]

A novel and efficient nanomagnetic palladium catalyst [Fe3O4@SiO2-Schiff base-Pd(0)] has been fabricated by attaching of a Pd (0) complex to magnetic nanoparticles through cheap, simple, and readily available chemicals. The as-fabricated Fe3O4@SiO2-Schiff base-Pd(0) nanomaterial was fully characterized by a number of spectroscopic techniques including FT-IR, SEM, TEM, EDX, XRD, VSM, TGA, elemental mapping and ICP-OES. The catalytic activity of the Fe3O4@SiO2-dipyridine-Pd nanocatalyst was investigated in the formation of C=O bonds through Suzuki coupling carbonylative reactions (the Suzuki cross-coupling of N–Ac amides by N−C cleavage). Under this method, aromatic benzamides and boronic acids with both electron-donating and electron-withdrawing substituents exhibit high reactivity and generate the corresponding diaryl ketones with high yields. The high efficiency and the ability to be recovered and reused for at least up to 8 consecutive runs are superior properties of the Fe3O4@SiO2-Schiff base-Pd(0) catalyst. [ABSTRACT FROM AUTHOR]

As a strategically important resource with stable properties, high-purity quartz plays a crucial role in various fields such as high-purity quartz crucibles, semiconductors, and electronics. Currently, the availability of high-quality quartz resources is gradually diminishing, and there are no high-quality quartz deposits in some areas, making the improvement of low-quality quartz essential. This study focuses on the quartz sand produced through river dredging in Yueyang. The detected SiO2 content is 92.31%, which enables the secondary utilization of waste resources and provides significant environmental benefits. In this study, the iron oxide removal efficiency achieved through magnetic separation pretreatment can reach 87.24%. Following flotation, calcination, and leaching processes, high-purity quartz products with a total impurity content of less than 100 ppm were successfully obtained. In addition, the factors affecting magnetic separation and calcination effect were studied, and the process parameters for reference were obtained. The mechanism of microwave impurity removal was investigated using SEM, TG-MS, and in-situ XRD, demonstrating the feasibility of producing high-purity quartz from low-quality quartz. [ABSTRACT FROM AUTHOR]

The High-Density Sludge (HDS) process is widely used for the treatment of acid mine water as it produces a sludge of high density. The aim of this study was the development of a process where iron in mine water can be removed as magnetite, to assist with rapid settling of sludge. It was concluded that Fe2+ can be removed as Fe3O4 (magnetite) by forming Fe(OH)2 and Fe(OH)3 in the mole ratio of 1:2. Magnetite can form in the absence or presence of gypsum. The settling rate of magnetite-rich sludge is substantially faster than that of ferric hydroxide-rich sludge. It is recommended that further studies be carried out on the separation of magnetite gypsum through magnetic separation. [ABSTRACT FROM AUTHOR]

High-purity quartz is an emerging strategic material that has been extensively used in the semiconductor and photovoltaic fields. Taking vein quartz from southern Anhui Province as an example, raw materials were processed by ultrasonic scrubbing-desliming, magnetic separation, flotation, high-temperature calcination, water quenching, hot-press acid leaching, and deionized water cleaning to prepare high-purity quartz sand. At the same time, the microscopic structure, inclusions, phase, mineral morphology, water content in inclusions, and trace impurities of the gangue samples were analyzed using an optical microscope, a laser Raman spectrometer, an X-ray diffractometer, a scanning electron microscope, an infrared spectrum analyzer, and an inductively coupled plasma mass spectrometer. The results showed that feldspar and muscovite were the main impurities. After purification, the total amount of 13 impurities in quartz sand was reduced to 28.66 μg/g, and the contents of the main impurity elements Al, Na, and Fe were 12.81 μg/g, 12.80 μg/g, and 0.52 μg/g, respectively. The mass fraction of SiO2 increased from 99.06% to 99.9972%. This shows that flotation, high-temperature calcination, and hot-pressing acid leaching are the keys to obtaining high-purity quartz sand. Fluoride-free flotation with the new collector XK02 can effectively realize the deep separation of quartz and mineral impurities. High-temperature calcination can form more cracks on the surface of quartz sand particles, and the mixed acid enters the open crack channels to effectively remove impurities from the inclusions. This method provides technical support for the preparation of high-purity quartz sand with high value and for the efficient utilization of quartz ore. [ABSTRACT FROM AUTHOR]

Chromite is considered a strategic mineral in the global economy. It is mainly used as an essential raw material in the production of stainless steel and other metal alloys due to its corrosion and heat resistance properties. High-grade chromite resources are gradually depleting; with the increasing chromite demand in metallurgical applications, studies have focused on exploring low-grade and alternative chromite sources. This study proposes a cost-effective processing flowsheet for the low-grade middle group 2 (MG2) chromite layer, a poorly explored chromatite seam within the South African bushveld igneous complex (BIC). The study involved mineralogical characterization followed by gravity and magnetic separation of the low-grade MG2 ore at 18.18% Cr2O3. Characterization by XRD and Auto-SEM revealed that the ore mainly consists of pyroxene, chromite, and feldspar, with other minerals in trace quantities. The gravity separation test by shaking table upgraded the chromite (Cr2O3) to 42.0% at high chromite recoveries, whereas the laboratory Slon wet high-intensity magnetic separation method (SLon WHIMS) upgraded the chromite in the feed to 42.95% grade at lower chromite recoveries. Desliming the sample before the gravity and magnetic separation tests significantly improved the separation. The magnetic separation tests further demonstrated that chromite within the MG2 layer is sensitive to magnetic separation due to its high iron content. The adapted flowsheet is proposed as a cost-effective flowsheet for processing the low-grade MG2 layer. The flow sheet can be optimized by conducting the SLon WHIMS tests at high intensities followed by fine gravity tests by spiral circuits to maximize the chromite recovery while achieving commercial chromite grades and a Cr:Fe ratio greater than 1.5. [ABSTRACT FROM AUTHOR]

Peroxymonosulfate (PMS)-based advanced oxidation processes have shown potential for the removal of organic contaminants; however, the preparation of catalysts with high degradation efficiencies and rapid reaction rates remains a challenge. In this study, we have successfully synthesized CoFe bimetallic modified corn cob-derived biochar (CoFe/BC) for the activation of PMS, achieving the rapid and efficient degradation of bisphenol F (BPF). The synthesized CoFe/BC catalyst demonstrated excellent catalytic performance, achieving over 99% removal within 3 min and exhibiting a removal rate of 90.0% after five cycles. This could be attributed to the cyclic transformation of Co and Fe, which sustained rapid PMS activation for BPF degradation, and Co0/Fe0 played a significant role in the cyclic transformation. Furthermore, the electron paramagnetic resonance tests confirmed that •SO4− and •OH were the primary reactive oxygen species, while •O2− played a minor role in BPF degradation. This study highlights the high degradation efficiency, rapid reaction rate, excellent magnetic separation properties, and exceptional reusability of CoFe/BC catalysts for BPF removal, providing valuable insights for practical wastewater treatment. [ABSTRACT FROM AUTHOR]

In this research, we first fabricated Fe3O4@Dop-Triazine-CuCl2 nanocatalyst by simple method, then its catalytic activity was investigated in the preparation of various derivatives of aryl-heteroaryl and di-heteroaryl selenides through C–Se coupling reactions of aryl iodides with powder selenium and various derivatives of heterocyclic compounds (with active C–H bonds). The catalyst exhibited spherical morphology with a diameter of approximately 20–30 nm and a magnetic saturation moment of 50.032 emu/g. The hydrocarbon content was measured to be around 12% by weight. In this method, a wide range of aryl-heteroaryl and di-heteroaryl selenides (36 examples) were synthesized with high yields (85–97%) using catalytic amount of the Fe3O4@Dop-Triazine-CuCl2 nanomaterial in the presence of KHCO3 in [BMIM]PF6 as solvent. This method has several remarkable features, which can be mentioned as follows: the synthesis of aryl-heteroaryl and di-heteroaryl selenide derivatives with high yields, performing the reactions in a suitable time (4 h), the applicability of this catalytic system for a wide range of substrates, the use of ionic liquid as solvent, high efficiency of Fe3O4@Dop-Triazine-CuCl2 catalyst, simple separation and high reusability of nanocatalyst. [ABSTRACT FROM AUTHOR]

It is very important to properly treat uranium-containing wastewater scattered in the environment. In this study, we used the hydrothermal method to synthesize carbon-coated magnetic Fe3O4 nanoparticles and then modified by sodium hydroxide to yield magnetic carbon nanomaterials (Fe3O4@HTC-NaOH). The microstructure and chemistry of the material were characterized by TEM and FTIR. We investigated the adsorption behavior of materials for uranium (VI) under different conditions, including pH, contact time, initial uranium concentration, and temperature. The results indicated that this material adsorbs uranium quickly, achieving equilibrium in static adsorption after approximately 225 min. The adsorption behavior was strongly dependent on pH, and the maximum adsorption capacity (457.83 mg/g) was reached at pH 5.5. The initial concentration also had a role in the adsorption behavior. With the gradual increase of the initial concentration of uranium (VI), the adsorption capacity showed an increasing trend and reached saturation at 100 mg/g. Adsorption isotherm could be well fitted by the Langmuir model and the pseudo-second-order kinetic model. And the results indicated it is a heat-absorbing reaction. Owing to the introduction of Fe3O4, the material is magnetic and the solid-liquid separation can be rapidly completed by the pairing of magnets. The new material could be regenerated using HNO3, and the adsorption rate could maintain above 75% after five adsorption/regeneration cycles, which illustrated its certain practical application value. [ABSTRACT FROM AUTHOR]

This study aimed at the investigation of the effect of colloidal magnetic particles on the magnetic separation of iron ore tailings (IOT). For this, the synthesis and characterization of bare iron, iron-dextran, and iron-oleate magnetic particles is reported. FTIR spectra confirmed that the synthesized particles were composed by magnetite. In general, the iron recovery was superior when magnetic particles were introduced, regardless of the addition of bare magnetic or functionalized iron particles. When iron-crosslinked-dextran particles were added into the pulp at the dosages of 0.5 and 1.0 g/t, an increase in recovery of about 7% took place at 0.34 T, but with a loss in grade of about 5%. Further cleaning stages are necessary to reduce the silica content. This work is aligned with the sustainability needs of mining operations, constituting an alternative technology for the reuse of iron ore tailings. [ABSTRACT FROM AUTHOR]

Many studies relating to the preparation of magnetic composites from various raw materials have been reported. However, for the first time, the magnetic Fe‐decorated carbon nanosheets (FeCNs) were prepared using waste facemasks with iron‐containing nose strip as both carbon source and iron source. The uniform decoration of Fe3O4 nanoparticles not only endows carbon matrix with magnetic separation property but also enriches the lamellar structure to furnish more catalytically active sites. The as‐prepared FeCNs nanozymes behave optimal peroxidase‐like activity under pH of 4 and temperature of 50°C, excellent reusability, and substrate affinity. Based on FeCNs, a convenient colorimetric strategy was successfully constructed for flavonoid detection in simulated and real samples. Experimental and theoretical results show that hydroxyl radicals (•OH) and superoxide radical (•O2−) are the major active species in the reactions that are catalyzed by FeCNs in the presence of H2O2. And the generation of these radicals can be attributed to the electron transfer between Fe2+/Fe3+ pairs and H2O2 molecules. This work provides a new way for preparing magnetic carbon‐based nanozymes and realizes the resource utilization of waste facemasks. [ABSTRACT FROM AUTHOR]

The BixOyIz and CoFe2O4 combination enhances photocatalytic degradation of tetracyclines (TCs). Three TC antibiotics including TC, oxytetracycline (OTC), and chlortetracycline (CTC) with high concentration (50 mg L−1) were utilized as target pollutant. Bi5O7I/Bi4O5I2, with its Z‐scheme, improves removal efficiency to 1.6 times that of Bi5O7I and 1.4 times that of Bi4O5I2. Ternary Bi5O7I/Bi4O5I2/CoFe2O4 (I/I/Co) composites further increase efficiency, with I/I/Co‐2 achieving 1.6 times that of I/I‐2. The improved performance is due to an optimized microstructure, which promotes light absorption and carrier transfer. CoFe2O4 nanoparticles on nanosheets create a double‐Z band structure, enhancing redox activity. Radical trapping experiments indicated the major active species (•O2−, OH−, and h+) in photocatalytic process of I/I/Co‐2. Based on their enhanced removal efficiencies for high‐concentration TCs, proper magnetic separation capacity, and recycling performance, the practical applications of I/I/Co composites to treat real TC wastewater might be implemented. [ABSTRACT FROM AUTHOR]

After the purification of crude tea saponin through the method of n-butyl alcohol extraction or macroporous resin adsorption, the impact of purification on the separation of alcohol dehydrogenase related active components (AAC) from purified tea saponin by magnetic immobilization enzyme was investigated. The results demonstrated a reduction in polysaccharides and polyphenols in the purified samples, while significantly increasing the content of tea saponin. Specifically, the content of tea saponin in the purified samples obtained through extraction method and macroporous resin adsorption method was 19.8% and 18.5% higher than that of crude tea saponin, respectively. When these purified samples were utilized for the separation by magnetic immobilization, it effectively minimized enzyme activity loss ratio associated with immobilized enzymes. Notably, macroporous resin adsorption exhibited the lowest loss ratio at 27.8%. Spectral characteristics analysis revealed no changes in AAC obtained before and after purification; they remained predominantly composed of tea saponins. Furthermore, there were no significant alterations observed in AAC's inhibitory effect on alcohol dehydrogenase; this inhibitory effect remained concentration-dependent as well. Therefore, purifying crude tea saponin can reduce enzyme consumption during magnetic immobilized enzyme separation process while enhancing reusability without significantly affecting AAC. [ABSTRACT FROM AUTHOR]

The object of the research is technologies and technical means for selective destruction of mineral matrices of complex multicomponent titanium ores of primary deposits and beneficiation of minerals with altered magnetic properties. The aim of the work is to increase the efficiency of enrichment of titanium-iron ores by preliminary high-temperature treatment using new-type separators. This is achieved by substantiating the targeted selective destruction of mineral complexes and changing the magnetic properties of ore minerals as a result of temperature-controlled oxidation reactions. Methods of complex generalization, analysis and evaluation of practical experience and scientific achievements in the field of creation and introduction of new technologies and technical means for increase of efficiency of enrichment of titanium ores on the basis of separators of new type by substantiation of the directed selective destruction of mineral complexes and change of magnetic properties of ore minerals are described. It was found that for ilmenite, the main titanium component of raw materials, a low mass fraction of titanium is typical - no more than 30.0%, and ilmenite has lamellar-thin nano inclusions of hematite - 31.53 vol. %, which are difficult to remove from the ilmenite matrix. It is proved that in titanium-containing ores selective opening of splices occurs due to recrystallization of grains due to previous reduction, strengthening of bonds in hematiteilmenite contact zones and non-ore inclusions and creation of a network of germinal cracks inside nano splices due to exposure to mineral matrix. C. It is shown that the use of magnetic separation of raw materials after high-temperature treatment reduces the mass fraction of harmful elements such as silicon, aluminum and calcium oxides from 11.89 to 1.2% in the concentrate product and allows to increase the mass fraction of titanium oxide from 32.3 up to 37.6%, and total iron from 33.86 to 42.29%; The technology of complex ore beneficiation has been developed to provide concentrates used for the extraction of titanium slag (mass fraction of titanium oxide - 80-81.84%) and high-purity metallic iron Fe with an average chemical composition of Fe 0.993 Ti 0.006. The results of development and implementation of new generation technologies and separators in the enrichment and processing of titanium ore were obtained in the laboratories of the State Higher Educational Institution (KVUZ) "Kryvyi Rih National University" (Krivoy Rog, Ukraine) and implemented at the Public Joint Stock Company (PJSC) » (Zaporozhye, Ukraine) and the State Institute for the Design of Mining Enterprises SE" Krivbasproekt "(Krivoy Rog, Ukraine). The developed technologies are also the basis for the feasibility study of ore processing technology of the Abu Galaga field (Egypt), in the design of the industrial complex and can be useful for other enterprises in developed mining countries. Research and implementation of new technologies and technical means using dry magnetic separation will allow for the stable production of high-quality concentrates, as well as the reduction of the grinding and enrichment front by at least 15–20% of the original, which will reduce operating and capital costs by more than 30% and will become a powerful technological reserve for the development of mining production. [ABSTRACT FROM AUTHOR]

The inability of surgical biopsy to monitor the dynamic evolution of cancer cells hampers its capacity to reflect real-time tumor heterogeneity. Circulating tumor cells (CTCs), as a crucial target in liquid biopsy, offer a novel approach for accurate monitoring of tumors. However, the rarity and complex phenotype resulting from epithelial-mesenchymal transition pose challenges for conventional methods such as CellSearch and immunohistochemistry, which have insufficient ability for simultaneous phenotyping and enumeration of CTCs. The enumeration of a single phenotype CTCs is insufficient for accurately assessing disease progression. Herein, we propose a strategy to address this issue by fabricating an electrochemiluminescence cytosensor via the integration of dual-target enrichment and nanozymes-catalyzed cascade signal amplification. The graphene oxide@hollow mesoporous Prussian blue/Pt (GO@HMPB/Pt) complex, possessing a large specific surface area and exceptional catalytic activity, is employed for loading a substantial amount of luminol as the signal probe. Dual-target magnetic PPy@Fe3O4/Au-antibody/aptamer is utilized for the magnetic capture of both epithelial and interstitial CTCs. Glutathione (GSH) can disrupt the Au–S bond on aptamer by a thiol exchange reaction and selectively releases a specific subset of phenotypic CTCs, thereby facilitating the efficient capture, accurate classification, and ultrasensitive detection of CTCs in peripheral blood. Using the epithelial MCF-7 and mesenchymal Hela cells as models, the ECL cytosensor demonstrates excellent performance in identifying cells spiked into whole blood. This study presents a novel approach for early detection of metastasis, tracking tumor recurrence, and monitoring therapeutic efficacy. [ABSTRACT FROM AUTHOR]

The determination of the amount and composition of artificial polymer microparticles in ponds requires the preparation of representative water samples. A new method has been proposed in this work for magnetic separation of polyethylene microparticles (PEMPs, 10–200 μm), with the method implying their aggregation with magnetic nanoparticles. Composite magnetic nanoparticles containing magnetite cores and silica shells functionalized with amino groups (Fe3O4@SiO2–NH2, dhydr = 200 nm) have been synthesized and characterized. Due to electrostatic interactions, these nanoparticles can form aggregates with polyethylene particles and be separated from water under the action of a gradient magnetic field. The effects of added salts (NaCl, Na2SO4, NaH2PO4, and CaCl2) and a surfactant, sodium dodecyl sulfate (SDS), on the separation conditions of PEMPs from water have been studied. It has been shown that the addition of the magnetic particles in concentration c = 0.01 g/L to aqueous suspensions containing NaCl and NaH2PO4 (c = 10 mM), and SDS (c = 3 mM) provides an efficiency of magnetic separation of PEMPs equal to, at least, 98% after preliminary exposure for 30 min and magnetic sedimentation for 15 min. As the concentration of NaCl and NaH2PO4 is increased to 100 mM or in the presence of Na2SO4, the efficiency of PEMP magnetic separation decreases. In the presence of CaCl2 and SDS, the efficiency of the magnetic sedimentation is no less than 98% at the studied concentrations of the salts. At least 80% of PEMPs are separated by magnetic filtration from model solutions simulating river and sea water within 5 min. [ABSTRACT FROM AUTHOR]

Continuous monitoring of pathogens finds applications in environmental, medical, and food industry settings. Quartz crystal microbalance (QCM) is one of the promising methods for real-time detection of bacteria and viruses. QCM is a technology that utilizes piezoelectric principles to measure mass and is commonly used in detecting the mass of chemicals adhering to a surface. Due to its high sensitivity and rapid detection times, QCM biosensors have attracted considerable attention as a potential method for detecting infections early and tracking the course of diseases, making it a promising tool for global public health professionals in the fight against infectious diseases. This review first provides an overview of the QCM biosensing method, including its principle of operation, various recognition elements used in biosensor creation, and its limitations and then summarizes notable examples of QCM biosensors for pathogens, focusing on microfluidic magnetic separation techniques as a promising tool in the pretreatment of samples. The review explores the use of QCM sensors in detecting pathogens in various samples, such as food, wastewater, and biological samples. The review also discusses the use of magnetic nanoparticles for sample preparation in QCM biosensors and their integration into microfluidic devices for automated detection of pathogens and highlights the importance of accurate and sensitive detection methods for early diagnosis of infections and the need for point-of-care approaches to simplify and reduce the cost of operation. [ABSTRACT FROM AUTHOR]

Microwave heating is an eco-friendly and novel technique for sintering and heating minerals and materials as it has several advantages in terms of phase transformation, energy efficiency, enhancing speed, process simplicity, improved properties. Such heating provides the composite materials to absorb electromagnetic energy volumetrically and transform into heat and produces larger densities as compared to conventional heating. This study focuses on two main objectives: the recovery of ilmenite through a strategic combination of mineral processing equipment, including a spiral concentrator, followed by magnetic and electrostatic separation, and the enhancement of ilmenite concentrate using microwave heat energy on a cleaner magnetic product, followed by electrostatic separation. Continuous magnetic separation results indicate that among the dry high-intensity belt magnetic separator, box mag wet high-intensity magnetic separator and dry rare earth drum magnetic separators, the rare earth magnetic separator yielded the highest quality product. The application of microwave heat energy before the rare earth drum magnetic separator at 1.4 T, followed by high-tension separation, produced the best grade of ilmenite. The magnetic product obtained after microwave treatment contained 98.6% ilmenite, which was further upgraded to a 99.6% ilmenite concentrate through high-tension separation. Therefore, it is recommended that an effective combination of gravity separation, microwave heat energy, rare earth drum dry magnetic separation and high-tension separation be employed to achieve the highest grade of ilmenite concentrate. [ABSTRACT FROM AUTHOR]

Quartz sand is a high-end raw material with excellent physical and chemical properties derived from quartz stone. China heavily relies on imports for quartz, with the proportion of high-purity quartz being low in the market. Therefore, it is strategically important to strengthen independent technological research and development to efficiently utilise China's quartz sand resources. This work summarises and explains the physical and chemical properties of quartz, including its chemical components, phase composition, element existing state and embedded particle size. It also summarised various physical purification methods, such as colour separation, scrubbing–grading desliming, gravity concentration, magnetic separation and flotation. The work focused on the two major chemical purification methods, hydrometallurgy and pyrometallurgy, and clarified the challenges and dilemmas in quartz purification, such as high energy consumption, incomplete impurity removal and environmental pollution. On this basis, a green and efficient purification process for quartz sand, combining nonfluorinated acid leaching and microwave roasting, was proposed. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles are efficient catalytic systems for various reactions because of their high efficiency and easy separation. Amongst magnetic nanoparticles, copper ferrite (CuFe2O4 NPs) is one of the different types of ferrites, which is widely used in catalytic reactions because of its magnetic properties. On the other hand, deep eutectic solvents (DESs) consisting of a hydrogen bond acceptor component and a hydrogen bond donor component have recently attracted the attention of many researchers as green solvents. ChCl-urea is considered a green DES that has been reported several times to carry out chemical reactions. In recent years, research on the synthesis of 2-thioaryl-benzothiazoles and 2-thioaryl-benzoxazoles (compounds containing C-S aryls and benzothiazoles and benzoxazoles scaffolds) has become an attractive challenge in organic chemistry. In this research, we report the synthesis of 2-thio-benzothiazoles and 2-thioaryl-benzoxazoles by CuFe2O4 NPs in ChCl-urea as an efficient nanocatalyst. These compounds were synthesized via a one-pot, three-component coupling reaction of benzoxazoles or benzothiazoles with aryl iodides and S8 as a sulfur source in the presence of KOAc as a base. [ABSTRACT FROM AUTHOR]

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High-phosphorus oolitic hematite is recognized as one of the most refractory iron ores due to the intergrowth of phosphorus and iron, making traditional separation techniques ineffective. Gas-based direct reduction followed by magnetic separation is of significance to realize the efficient recovery of iron from low-grade iron ore, accompanying the reduction of phosphorus. However, the transformation and migration behavior of phosphorus during the reduction process remains unclear. To simulate the direct reduction of this ore, the initial heating followed by the reduction experiments were performed. Using confocal laser scanning microscopy (CLSM), this study first investigated the phosphorus transformation under a high-purity Ar atmosphere heating from 25 °C to 1500 °C. The results indicate that fluorapatite (Ca5(PO4)3F) underwent a sequence of defluorination, partial dissolution, and complete dissolution, corresponding to solid (Ca3(PO4)2), solid-liquid coexistence, and liquid phases (P2O5), respectively. Subsequently, the migration behavior of three kinds of phosphorus in different states during CO reduction was clarified through a quantitative mass balance analysis. At 1200 °C, solid Ca3(PO4)2 was not reduced by CO. By 1300 °C, (P2O5) in the melt was reduced, and more than half of phosphorus escaped to the gas phase. The increase in dissolved (P2O5) in the melt accelerated the reduction of phosphorus at 1400 °C, resulting in an increase of phosphorus in the iron phase. Finally, inhibiting (P2O5) dissolution in the melt via Al2O3 addition could decrease phosphorus content in the iron phase, providing a visible strategy to promote the utilization of high-phosphorus iron ores. [ABSTRACT FROM AUTHOR]

Copyright of Mining & Metallurgical Engineering is the property of Mining & Metallurgical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The carbothermic reduction of ilmenite concentrate was performed with the addition of calcium carbonate (CaCO3) as an additive. The effects of roasting temperature and CaCO3 content on calcium titanate (CaTiO3) formation and metallic iron reduction were investigated. The Rietveld method was employed for qualitative and quantitative analysis of roasting products. It was found that as the temperature increased from 1000 °C to 1400 °C, the calcium titanate content increased from 21.95% to 83.02%. Similarly, as the CaCO3 content increased, the calcium titanate content rose from 0% to 83.11%, while the metallic iron content increased from 4.52% to 10.37%. SEM-EDS analysis suggested that adding CaCO3 during the carbothermic reduction of ilmenite promoted the aggregation and growth of metallic iron particles. The roasting products obtained under optimal conditions were subjected to three-stage grinding and three-stage magnetic separation. The final metallic iron product had a grade of 90.01% and a recovery rate of 91.32%. The calcium titanate product contained 55.43% TiO2, with a titanium recovery rate of 85.90%. Rietveld results indicated that the calcium titanate product had a high purity, with a content of 90.87%. This study effectively improved the comprehensive utilization of titanium and iron resources in ilmenite. [ABSTRACT FROM AUTHOR]

Toxic heavy metal ions pose a significant threat as they contaminate wastewater, persist for long periods without breaking down naturally, and pose risks to human health and ecological balance. In order to assist with this task, microwave-assisted preparation was utilized to create efficient chitosan (CHN), manganese ferrite (Mn-Ferrite), and modified chitosan ferrite (CHN-Ferrite). There was a noticeable change in the phase crystallinity of pure Mn-Ferrite when CHN was added. Clusters comprised of cubic particles with a dark hue and a diameter of no more than 20–35 nm are also discernible. Additionally, the Mn-Ferrite compound experiences a significant boost in thermal stability due to the increased interaction between the CHN and Mn-Ferrite nanocomposite. The adsorption efficiency can attain a maximum value at pH 6 owing to the synergistic effect of CHN-Ferrite. The maximum degree of elimination was acquired employing magnetic separation of CHN-Ferrite (98.2%), CHN (91.3%), and ferrite in isolation (85.6%), utilizing a dosage of 0.07 g. The arrangement of amino aspects within the framework aligns with the magnetic field region, leading to the selective attachment of Pb2+ particles. The Langmuir isotherm exhibited R2 values exceeding 0.99 for Pb+2 ions in each sample. The remarkable capacity of the CHN-Ferrite adsorbent to adsorb Pb2+ ions with cost-effectiveness is commendable in addressing the issue of water contamination. [ABSTRACT FROM AUTHOR]

Thousands of species of parasitic weeds, such as dodder, pose significant threats to agricultural crops due to their ability to spread rapidly through seeds. When cultivated lands become infested with dodder, the quality of production declines, leading to substantial damage. The most effective way to limit the infestation of agricultural lands by parasitic weeds, particularly dodder, is to control the quality of seeds intended for sowing. To obtain seed material free of dodder seeds, special separation machines equipped with magnetic drums are used. These machines operate on the principle of magnetic fields acting on ferromagnetic particles, which helps differentiate the physical states of the seeds intended for separation. This paper presents experimental research on magnetic drum separation techniques for removing dodder seeds from alfalfa seed mixtures. The study examines variables such as magnetic drum speed, feed rate, amounts of iron powder, water, solution (water and glycerin), and the initial content of dodder seeds. The experimental results indicated that using a water–glycerin solution at optimal concentrations for moistening the seeds enhances the separation efficiency of dodder seeds from alfalfa seed mixtures, compared to using only water. Additionally, the numerical content of dodder seeds in the A and C sorts, which primarily contain the seeds of the main crop, decreases with each pass through the machine, resulting in higher quality seed material. The research found that using appropriate parameters—drum rotation speed (20 rpm), iron powder quantity (19 g/min), and seed feed rate (25.39 g/s)—achieved a "free" classification for dodder in alfalfa seeds. These findings are valuable for evaluating the performance of separation equipment with magnetic drums to obtain high-quality seed material. They are also beneficial for designers, machine-building units, and economic agents specializing in this field. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extracellular antibiotic resistance genes (eARGs) have emerged as significant environmental contaminants due to their role in the transmission and proliferation of antibiotic-resistant bacteria, posing a major threat to global health. Traditional detection methods for eARGs require complicated equipment, lengthy analysis times, and relatively low selectivity. Furthermore, eARGs are present in low concentrations in surface water samples, which presents considerable challenges to the sensitivity of detection assays. Therefore, there is an urgent need to develop more accessible, stable, and sensitive detection methods. In this work, we developed an ultrasensitive upconversion nanosensor utilizing a dual-amplification strategy for the detection of trace eARGs (bla-TEM). The upconversion nanosensor was activated upon the capture of bla-TEM and subsequently enriched through magnetic separation. Following this, a cascade nicking-polymerization amplification process occurred in a single reaction facilitated by a magnetic capture probe, an upconversion recognition probe, and the relevant enzymes. The upconversion nanosensor functions as both the direct target-recognizing moieties and signal reporters, replacing the energy donor in conventional luminescence resonance energy transfer-based upconversion nanosensors. Ultimately, the strategy demonstrated excellent sensitivity with a limit of detection (LOD) of 0.093 aM, rapid detection in less than one hour, good selectivity, and high accuracy compared to conventional polymerase chain reaction (PCR) assays. These findings provide valuable insights for the development of ultrasensitive detection assays for emerging environmental pollutants. [ABSTRACT FROM AUTHOR]

This work aims to evaluate the use of a superabsorbent polymer (SAP) to provide improvements in the handling properties of iron ore tailings (IOT). The material studied came from the magnetic separation reprocessing of the material discarded at the Gelado Dam, located in Serra dos Carajás in the state of Pará, Brazil. While the concentrate presents reasonable handling conditions, the tailings, with 61.5% iron, 15% moisture, and 39% of the mass, have high cohesiveness and adhesiveness due to their fine nature and the climatic conditions of the Amazon rainforest. However, the tailings can still be considered a product as long as the handling and transportation logistics are feasible. Thus, studies with an SAP and IOT were carried out in a bench rotating drum to promote mixing between them, and the main variables studied were the SAP dosage and the required contact time. The improvement in the physical properties of the IOT were evaluated considering the Hausner ratio, Carr index, Jenike's flow function index, Atterberg limits, and chute angle. The superabsorbent polymer promoted a significant improvement in the state of consistency of the material, and the best performance was obtained with a dosage of 1000 g t−1. As long as a suitable contact condition was promoted, a contact time of 1 min was enough to achieve the expected benefits. After dosing with the superabsorbent polymer, the material's handling classification changed from 'cohesive' to 'easy flow', and the chute angle was reduced from 90° to levels below 60°. It was concluded that the application of the superabsorbent polymer has the potential to improve the fluidity of the material discarded in the magnetic concentration operation, allowing it to be handled throughout the production and transportation chain. The SAP appears to be an important additive for the full use of the material present in the dam (100% recovery), with both economic and socio-environmental benefits. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Magnetic nanoparticles (MNPs) are appealing materials as assistant to resolve environmental pollution issues and as recyclable catalysts for the oxidative degradation of resistant contaminants. Moreover, they can significantly influence the advancement of medical applications for imaging, diagnostics, medication administration, and biosensing. On the other hand, due to unique features, excellent biocompatibility, high curie temperatures and low cytotoxicity of the Iron-based nanoparticles, they have received increasing attention in recent years. Using an external magnetic field, in which the ferrite magnetic nanoparticles (FMNPs) in the reaction mixtures can be easily removed, make them more efficient approach than the conventional method for separating the catalyst particles by centrifugation or filtration. Ferrite magnetic nanoparticles (FMNPs) provide various advantages in food processing, environmental issues, pharmaceutical industry, sample preparation, wastewater management, water purification, illness therapy, identification of disease, tissue engineering, and biosensor creation for healthcare monitoring. Modification of FMNPs with the proper functional groups and surface modification techniques play a significant role in boosting their capability. Due to flexibility of FMNPs in functionalization and synthesis, it is possible to make customized FMNPs that can be utilized in variety of applications. This review focuses on synthesis, modifications, and applications of Iron-based nanoparticles. [ABSTRACT FROM AUTHOR]

Research on the synthesis of imidazo[1,2-a]pyridines has gained great importance among synthetic chemists because there have been numerous reports of their biological and medicinal activities. In this respect, we fabricated CuCl2 immobilized on Fe3O4 nanoparticles modified with 1,10-phenanthroline-5,6-diol [Fe3O4@Diol/Phen-CuCl2] and investigated its catalytic activity for the preparation of imidazo[1,2-a]pyridine derivatives through one-pot three-component reaction of 2-aminopyridines, aldehydes and terminal alkynes under ecofriendly conditions. FT-IR spectroscopy, EDX, SEM, TEM, XRD, TGA, VSM and ICP-OES techniques employed in order to identify the structure of the as-constructed Fe3O4@Diol/Phen-CuCl2 nanocatalyst. This catalytic system has a series of advantages such as the synthesis of imidazo[1,2-a]pyridine products with high yields in suitable time, performing the reactions in an environmentally friendly solvent (PEG), easy preparation of the catalyst with a simple method, and the recyclability of the Fe3O4@Diol/Phen-CuCl2 nanocatalyst. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Efficient extraction of DNA from biological fluids is crucial for applications in molecular biology, forensic science, and clinical diagnostics. However, traditional DNA extraction methods often require costly reagents and lengthy procedures. This study aims to optimize the binding buffer composition for DNA extraction using polyethyleneimine-coated iron oxide nanoparticles (PEI-IONPs), which offer the dual benefits of magnetic separation and high DNA-binding efficiency. Methods: The effects of three key binding buffer components—polyethylene glycol (PEG-6000), sodium chloride (NaCl), and pH—on DNA adsorption efficiency were systematically evaluated. Blood samples were treated with PEI-IONPs under various conditions, and DNA concentration, yield, and purity were quantified. Nanoparticle functionalization was confirmed through characterization, and DNA quality was validated via agarose gel electrophoresis. Results: The optimized binding buffer composition consisted of a PEG-6000 concentration of 30%, NaCl concentration of 0M, and pH of 4, which yielded the highest DNA concentration (34 ± 1.2 ng/μL), yield (6.8 ± 0.2 μg), and purity (A260/A280 ratio of 1.81). These conditions significantly improved DNA recovery compared to suboptimal buffer compositions. Conclusion: The findings highlighted the critical role of binding buffer composition in maximizing DNA recovery. The use of optimized PEI-IONPs provided a rapid and efficient method for DNA extraction, supporting its potential for applications in scientific and clinical research. Future studies should explore the robustness of these optimized conditions across diverse biological fluids and extraction settings. [ABSTRACT FROM AUTHOR]

Plastic debris is unavoidably released into the ecosystems, and their physicochemical and mechanical qualities deteriorate when exposed to the environment. This, ultimately, leads to the generation of tiny fragments of plastic, which are known as nanoplastics (<1000 nm) and microplastics (<5 mm). Over the past few years, the pollution of synthetic polymers has been reported in almost all the compartments of the environment across the globe. It is regarded as a hazard to both human health and natural systems. In addition, synthetic polymers act as vectors for contaminants as they can adsorb and accumulate contaminants from seawater. The accumulation of plastic waste in the environment and its widespread presence have drawn the attention of policymakers and the public. This global issue has led to the creation of numerous remediation solutions by innovators in previous decades, either to clear up old waste or to stop plastic from entering the various matrices of the environment. This review focused on the extensive scientific research available on effective techniques for removing plastic debris to promote positive action and progress in this important area. Despite the various challenges, these techniques offer vital opportunities, from increasing awareness to enhancing environmental quality. Further, the article has been enriched by incorporating bibliometric data that illustrates the widely used methods for removing microplastics from various environmental matrices. According to the data analysis, numerous remediation techniques have been developed to date (2010 and 2024). These techniques encompass various approaches, among which the chemical‐based methods enjoy more success. This success can be attributed to the diverse advantages offered by chemical‐based methods over other remediation techniques. Much research is now focused on overcoming the disadvantages and developing more efficient and environmentally sound technologies. [ABSTRACT FROM AUTHOR]

A ratiometric electrochemiluminescence (ECL) aptamer-based sensing platform was fabricated for prostate-specific antigen (PSA) determination. Activated CdS nanocrystals/multi-walled carbon nanotubes (CdS/MCNTs) and luminol-Pt/PAMAM nanocomposites (L-Pt/PAMAM NCs) were synthesized and used as cathodic and anodic ECL emitters, respectively. Amino group–modified aptamers were assembled on carboxylated magnetic beads, followed by hybridization with probe DNA functionalized L-Pt/PAMAM NCs. In the presence of PSA, the aptamer would bind specifically to the target PSA, thereby releasing L-Pt/PAMAM NCs. After magnetic separation, the separated L-Pt/PAMAM NCs would hybridize with capture DNA on CdS/MCNTs coated on glassy carbon electrode. This binding would lead to a decrease in cathodic ECL signal of CdS/MCNTs, due to the efficient energy transfer from CdS/MCNTs to L-Pt/PAMAM NCs. Meanwhile, L-Pt/PAMAM brought the anodic ECL signal from luminol. With the increase of PSA concentration, the ECL emission from luminol increased and the ECL emission from CdS/MCNTs decreased. The ratio of ECL intensity of luminol at 0.55 V and CdS/MCNTs at − 1.25 V could be used to quantify the concentration of PSA. This method enables sensitive and reliable detection of PSA over a wide range from 0.05 to 200 ng mL−1, and the detection limit is 0.02 ng mL−1. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer stem cells (GCSCs) are key contributors to tumorigenesis, recurrence and metastasis, complicating gastric cancer (GC) treatment. Rhaponticin (RA), a potential novel anticancer drug, has unexplored effects on GCSCs. Methods: GCSCs were isolated using CD133 and CD166 markers with magnetic bead separation method and then evaluated their response to the IC50 concentrations of RA (16.90 µg/mL for BGC-823 and 22.18 µg/mL for SGC-7901), and effects on cell proliferation, migration, invasion, and stemness were measured. We analyzed the GCSC-related microarray dataset GSE111556 and explored RA's role in restoring programmed cell death ligand 1 (PD-L1) function in CD133+/CD166 + cells post-PD-L1 knockdown. RA's impact on tumour growth and immune microenvironment was assessed in a xenograft mouse model. Results: The CD133+/CD166 + subpopulation exhibited stem-like characteristics, with the highest proportion in BGC-823 (38.85%) and SGC-7901 (43.81%) cells. These cells formed tumour spheres and had increased expression of stemness markers Sox2 and Oct-4 (compared to the parental cell line, P < 0.001). RA treatment showed no toxicity to normal GES-1 cells but reduced the viability of CD133+/CD166 + cells in a dose-dependent manner, with IC50 values of 16.90 µg/ml for BGC-823 and 22.18 µg/ml for SGC-7901. RA also decreased the proportion of CD133+/CD166 + cells and their stem-like properties (P < 0.001). Analysis of the GEO database identified PD-L1 as a key target gene of RA, with high expression in GC tissues. Knocking down PD-L1 in CD133+/CD166 + cells and introducing RA did not significantly change PD-L1 expression (P>0.05), suggesting RA's effect may be PD-L1 dependent. In a xenograft mouse model, the tumour size in the RA treatment group was approximately one-sixth that of the CD133+/CD166 + group (P < 0.001). Post-RA treatment, there was an elevation in the expression levels of CD4 and CD8, alongside a reduction in PD-L1 expression (P < 0.001). Conclusions: RA suppresses GCSC stem - like phenotype by inhibiting PD - L1 and enhancing T cell tumour infiltration in the studied models. These findings suggest that RA may have potential for further exploration as a candidate for GC treatment, but extensive preclinical and clinical studies are required to determine its true therapeutic value. Highlights: The CD133+/CD166 + human GC cell subpopulation has the phenotypic characteristics of tumor stem-like cells. RA suppressed the stem-like cell phenotype of CD133+/CD166 + human GC cell subpopulation. PD-L1 is a key target gene of RA. RA prevents the stemness and aggressive phenotype of human CD133+/CD166 + GC cell subsets by inhibiting PD-L1. RA regulates the tumor microenvironment in CD133+/CD166 + xenograft mice by suppressing PD-L1. [ABSTRACT FROM AUTHOR]

Greigite (Fe3S4) and millerite (NiS) are important transition metal sulfides that exhibit light‐driven Fenton catalytic activity. In absence of light, they show limited activity. To utilize these properties without relying on light, we synergized these sulfides to prepare a composite Fe3S4–NiS (FSNS). Under fixed reaction conditions, the composite demonstrated excellent Fenton activity, degrading 93% of fast green dye (FG) and 98.1% of eriochrome black T dye (EBT) within a short reaction time. The mechanism involves electron transfer from the reduced sulfur state (S2−) in both NiS and Fe3S4 to the higher oxidation states of the metal ions viz. Fe3+and Ni3+ to facilitate the redox cyclization in the Fenton process. The catalyst showed high stability for five cyclical tests by recovering it from solution with an external magnet. [ABSTRACT FROM AUTHOR]

The removal and detection of highly toxic mercury(II) ions (Hg2+) in water used daily is essential for human health and monitoring environmental pollution. Efficient porous organic polymers (POPs) can provide a strong adsorption capacity toward heavy metal ions, although the complex synthetic process and inconvenient phase separation steps limit their application. Hence, a combination of POPs and magnetic nanomaterials was proposed and a new magnetic porous organic polymer adsorbent was fabricated by a green and mild redox reaction in the aqueous phase with trithiocyanuric acid (TA) and its sodium salts acting as reductive monomers and iodine acting as an oxidant. In the preparation steps, no additional harmful organic solvent is required and the byproducts of sodium iodine are generally considered to be non-toxic. The resulting magnetic poly(trithiocyanuric acid) polymers (MPTAPs) are highly porous, have large surface areas, are rich in sulfhydryl groups and show easy magnetic separation ability. The experimental results show that MPTAPs exhibit good adsorption affinity toward Hg2+ with high selectivity, rapid adsorption kinetics (10 min), a large adsorption capacity (211 mg g−1) and wide adsorption applicability under various pH environments (pH 2~8). Additionally, MPTAPs can be reused for up to 10 cycles, and the magnetic separation step of MPTAPs is fast and convenient, reducing energy consumption compared to centrifugation and filtration steps required for non-magnetic adsorbents. These results demonstrate the promising capability of MPTAPs as superior adsorbents for effective adsorption and separation of Hg2+. Based on this, the prepared MPTAPs were adopted as magnetic solid-phase extraction (MSPE) materials for isolation of trace Hg2+ from aqueous samples. Under optimized conditions, the extraction and quantification of trace Hg2+ in water samples were accomplished using inductively coupled plasma mass spectrometry (ICP-MS) detection after MSPE procedures. The proposed MPTAPs-based MSPE-ICP-MS method is efficient, rapid, sensitive and selective for the determination of trace Hg2+, and was successfully employed for the accurate analysis of trace Hg2+ in tap water, wastewater, lake water and river water samples. [ABSTRACT FROM AUTHOR]

In this method, a novel and efficient magnetically reusable catalyst [Fe3O4@DAPA-Pd(0)] was prepared through the immobilization of Pd(0) complex on Fe3O4 nanoparticles coated with 2,3-diaminopropionic acid and its catalytic behavior was evaluated in the preparation of sulfonamide derivatives through one-pot three-component reactions of aryl or heteroaryl iodides, amines and SO2 under ecofriendly conditions. A number of spectroscopic techniques including FT-IR, VSM, TGA, EDX, elemental mapping, TEM, SEM, XRD and ICP-OES techniques was used to identify the Fe3O4@DAPA-Pd(0) nanocatalyst. This method suggested a number advantages such as the preparation of sulfonamide products with high yields, identify the all sulfonamide products by HNMR and CNMR, the performance of the reactions in [BMIM]PF6 as green solvent, simple separation of the Fe3O4@DAPA-Pd(0) catalyst by an external magnet and high reusability of the catalyst. VSM, TEM, TGA and ICP-OES techniques was confirmed the high stability and efficiency of the recovered catalyst after 8 times. [ABSTRACT FROM AUTHOR]

Three quartz-rich geologic materials—vein quartz from the Great Bear Magmatic Zone, massive quartz from the Nechalacho rare earth deposit, and quartz sands from the Chedabucto silica sand deposit along the shores of the Northern Arm of the Great Slave Lake, Northwest Territories of Canada—were evaluated for their amenability to physical beneficiation into high-purity quartz (HPQ). The samples were subjected to various treatment processes, including crushing, grinding, calcining and quenching, acid leaching, wet high-intensity magnetic separation (WHIMS), and reverse flotation. After treatment, both the core and sand quartz samples met the requirements for HPQ, making them suitable for use in the production of semiconductor filters, liquid crystal displays (LCDs), and optical glass. However, the Al-bearing impurity content in the vein quartz products remained relatively high, and most of these impurities were dispersed in the quartz lattice, requiring further processing to meet the purity standards for HPQ required by these industries. [ABSTRACT FROM AUTHOR]

The combined pollution of organics and heavy metals represents a significant environ-mental problem that has attracted widespread attention. This explores the treatment of methylene blue (MB) and Cu(II), which are common pollutants in dye wastewater, and the recycling of Cu. A magnetized vaterite (V-M) was synthesized using Bacillus velezensis, and its structure and magnetic performance were investigated. The effects and mechanisms of removing MB-Cu(II) composite pollution using V-M and H2O2 in combination were estimated. The results indicated that V-M is a combination of organic and inorganic substances, with 21.5 wt% organic matter and multiple organic functional groups, including O-H, -SH, and others. The combination of V-M and H2O2 can achieve a maximum removal percentage of 90% for MB-Cu(II) pollution. The analysis showed that MB was oxidized by the ·OH generated from the H2O2-based Fenton-like reaction, and was catalyzed by the Fe3O4 in V-M. The immobilization of Cu(II) by V-M was mostly realized through the binding of the organic substances on the surface of the V-M, multilayer adsorption, and a replacement reaction with Ca(II). Magnetic separation and the addition of diluted HCl were used for the recycling of the Cu(II) enriched by V-M, with a recycling percentage reaching 85%. This study introduced a novel approach to the remediation of MB-Cu(II) composite pollution, and the recycling of Cu(II). [ABSTRACT FROM AUTHOR]

This paper presents the results of research on the possibility to obtain CRMs (REEs) and industrial metals (Zn) from slag as a waste generated as part of zinc and lead extraction processes. Physicochemical methods were used to separate CRM and Zn concentrates: magnetic separation, sintering with NaOH and leaching with selected mineral acids. After analysing the obtained results, it was found that the use of concentrated hydrochloric acid and a temperature of 363 K for leaching was effective in separating REEs from slags obtained from current production. The recovery rate in this case ranged from 83.73% for La to 98.03% for Eu. For slag samples (M1) obtained from current production from ZGH Bolesław S.A.(Poland) as well as HC Miasteczko Śląskie S.A. (Poland) and treated with concentrated HCl, the leaching level of Bi, Zn, Ni, Mn and P exceeded 90% compared to the content in the reference sample. For a historical slag sample from Ruda Śląska (Poland), treatment with concentrated HCl yielded a high leaching level of Cd (70.90%), Pb (78.66%), As (72.49%) and Mo (61.90%). A concentrate containing 1.64% of REEs and 67.1% of Zn was isolated from the solutions obtained after leaching by precipitation. An economic analysis of an REE concentrate extraction facility was also performed. For an operation of 17 years, the calculated NPV was −26,352,644 million EUR. The obtained results indicate that, for the analysed facility, recovering metals and critical raw materials from slag as a waste mass is not economically effective. [ABSTRACT FROM AUTHOR]

Xenotime (YPO4), a significant phosphatic minerl rich in heavy rare earth elements (HREEs), typically associates with granitic rocks, exemplified in the Wolverine rare earth deposit in Australia. A mineral composition analysis indicates that the primary valuable minerals in the deposit are principally xenotime and minor florencite, with quartz and illite as the main gangue minerals, showing a relatively simple mineral composition. The grade of rare earth concentrate was increased to 14.29% and the recovery reached 94.48% through the magnetic separation pre-enrichment test. However, a high-grade rare earth concentrate could not be achieved using magnetic separation alone. Further purification of the magnetic concentrate is conducted through flotation. The grade of rare earth concentrate reached 51.26%, and the recovery rate reached 90.47%. In summary, this process achieves the efficient recovery of xenotime and florencite, having substantial industrial potential. [ABSTRACT FROM AUTHOR]

Australia has large reserves of limonite and clay-based laterites that are currently underutilized. This review summarizes the latest nickel laterite upgrading studies reported in the literature which use physical beneficiation – only studies reported after the most recent review in 2015 included – as well as high-temperature methods involving oxidation/reduction roasting (with and without additives), sulphidation, and other high-temperature methods. The focus of this review is on upgrading limonite ores, but studies using other types of laterites are also discussed for comparative purposes. Oxidative roasting has proven to be ineffective but producing a magnetic phase by reduction roasting then magnetically separating it from gangue minerals has produced nickel grades and recoveries of up to 14% and 99% respectively with limonite ores. The choice of reductant has negligible effect although hydrogen reduction is predicted to occur at slightly lower temperatures and recoveries are slightly lower compared with carbon-based reductants. The addition of sulfurous compounds improves agglomeration of ferronickel particles, increases the nickel grade and recovery. The highest recovery of 97.91% (grade 13.62%) was reported when sulfur was used as an additive during the roasting of a limonite ore with coal and limestone at 1400°C for 6 h. The results show reduction roasting followed by magnetic separation is effective for upgrading nickel ores, but challenges with this technology are the potentially high reagent usage and temperatures required. The economic feasibility for processing limonite ores via this route is not clear and should be investigated further. [ABSTRACT FROM AUTHOR]

Natural minerals as catalysts have the advantages of wide source and environmental friendliness. However, it is still challenging to develop mineral-based NH3-SCR catalysts with high NO conversion and N2 selectivity at low temperatures. Therefore, we use magnetic separation rare earth tailings with certain catalytic activity and acidic sites as the carrier, and introduce metal elements Mo and Ce with different valence states as active components to stimulate the catalytic activity of magnetic separation rare earth tailings by multi-element co-doping. The catalysts were tested and analyzed by XRD, XPS, BET, NH3-TPD and other characterization methods. The results show that there is an electronic interaction between Fe, Mo and Ce on the surface of Mo-Ce/magnetic rare earth tailings catalyst. The increase of Fe3+, Mo5+ and Ce3+ promotes the adsorption of NH3 and NO on the surface of the catalyst. With the introduction of Ce, the redox capacity and Brønsted acid strength of the catalyst at low temperature are significantly enhanced, thus accelerating the SCR reaction. The results of this study not only provide a theoretical basis for the high-value utilization of magnetic separation rare earth tailings, but also expand the raw material range of NH3-SCR denitration catalyst. [ABSTRACT FROM AUTHOR]

This work extends the boundaries of a new technology for the complex processing of dust obtained from melting scrap metal in electric arc furnaces at a factory in Kazakhstan by extracting zinc and lead into commercial products. Comprehensive studies of the elemental and phase compositions of dust conducted using a JED-2300 scanning electron microscope showed high contents of zinc (more than 30%), lead (approximately 5%), and iron. A considerable part of the iron in the dust (up to 35%) is represented as magnetite. Because of the lack of rational processing technology, a large amount of dust has accumulated on the plant territory, which requires a solution for its disposal with complex extraction of precious metals. The general concept of the technology under development is based on an approach that ensures the disposal of multicomponent ferrous metallurgy dust to obtain a wide range of commodity products with high added value. At the same time, the high content of iron present as magnetite demonstrates the effectiveness of isolating iron as an iron-containing commercial product at the beginning of the technological scheme. This paper shows the fundamental possibility of separating iron from dust from the scrap metal melting in electric arc furnaces by magnetic separation. According to comprehensive studies, including the study of the material composition of the initial dust and magnetic separation products, magnetic dust separation produced an iron-containing product with a high (up to 68%) iron content. The residual minimum limit of the iron content in the nonmagnetic fraction in the form of magnetite has been established as 0.58%. Further processing of such material will considerably simplify the technology, reduce material costs, and improve product quality. [ABSTRACT FROM AUTHOR]

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, Fe3O4@SiO2 magnetic core-shell nanoparticles functionalized with 1,4- dihydroxyanthraquinone molecules were synthesized and used to remove divalent copper ions from aqueous solutions. Then, the structural, crystalline, surface morphology, nanoparticle size, magnetic properties and thermal stability of synthetic nanoparticles were determined using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, field emission scanning electron microscope, transmission electron microscope, vibrating sample magnetometer and thermal gravimetric analysis were investigated and identified. After the synthesis of magnetic nano adsorbent, the effect of different amount of adsorbent and study of absorption kinetics in the removal of divalent copper ions was investigated and the results showed that the use of 14 mg of adsorbent leads to the removal of copper ions with a maximum absorption of 96% at ambient temperature in a period of 28 minutes and at pH 7. Finally, the recyclability and reusability of Fe3O4@SiO2-DAQ in the copper ion adsorption-desorption process was investigated using a magnet and the results confirm that this synthetic nanocomposite is an effective adsorbent with excellent performance to remove divalent copper ions. [ABSTRACT FROM AUTHOR]