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Louisfuchsite (IMA 2022-024), with an end-member formula Ca2(Mg4Ti2)(Al4Si2)O20, is a new refractory mineral identified in a Ca-Al-rich inclusion (CAI) from the NWA 4964 CK3.8 carbonaceous chondrite. Louisfuchsite occurs with spinel, perovskite, grossmanite, plus secondary rutile, titanite, and ilmenite in three regions in the CAI. The mean chemical composition of type louisfuchsite by electron probe microanalysis is (wt%) Al2O3 25.48, SiO2 18.40, MgO 17.92, TiO2 15.36, Ti2O3 3.13, CaO 14.92, FeO 3.30, V2O3 0.67, Cr2O3 0.08, total 99.26, giving rise to an empirical formula of C a 2.00 (M g 3.44 T i 1.49 4 + F e 0.36 T i 0.34 3 + A l 0.24 V 0.07 3 + C a 0.06 C r 0.01 ) Σ 6.01 (A l 3.63 S i 2.37 ) Σ 6.00 O 20 . Louisfuchsite has the P 1 rhönite structure with a = 10.37(1) Å, b = 10.76(1) Å, c = 8.90(1) Å, α = 106.0(1)°, β = 96.0(1)°, γ= 124.7(1)°, V = 741(2) Å3, and Z = 2, as revealed by electron backscatter diffraction. The calculated density using the measured composition is 3.44 g/cm3. Louisfuchsite is a new refractory phase from the solar nebula, crystallized from an 16O-rich (Δ17O ~ –24 ± 2‰) refractory melt with the initial 26Al/27Al ratio of (5.09 ± 0.58) × 10–5 under reduced conditions. The mineral name is in honor of Louis Fuchs (1915–1991), a mineralogist at Argonne National Laboratory, for his many contributions to mineralogical research on meteorites. [ABSTRACT FROM AUTHOR]

Investigating mineral/melt Sn partitioning at high temperatures and pressures is a difficult task because Sn is a redox-sensitive multivalent element and easily alloys with noble metal sample capsules. To obtain accurate Sn partition coefficients between titanite, ilmenite, and granitic melts, we developed single capsule Pt or Au and double capsule Pt95Rh5 (or Au)-Re designs to avoid significant Sn loss at a controlled oxygen fugacity (fO2). With these new capsule designs, we performed piston-cylinder experiments of Sn partitioning between titanite, ilmenite, and granitic melts. The experimental P-T-fO2 conditions were 0.5–1.0 GPa, 850–1000 °C, and ~QFM+8 to ~QFM-4 (quartz-fayalite-magnetite, QFM, buffer), with fO2 controlled by the solid buffers of Ru-RuO2, Re-ReO2, Co-CoO, graphite, and Fe-FeO. The obtained mineral/melt Sn partition coefficients ( D S n m i n / m e l t ) are 0.48–184.75 for titanite and 0.03–69.45 for ilmenite at the experimental conditions. The D S n m i n / m e l t values are largely dependent on fO2, although the effects of temperature and melt composition are also observed. D S n T t n / m e l t strongly decreases with decreasing fO2, from ~46–185 at the most oxidizing conditions (Ru-RuO2 buffer), to ~2–16 at moderately oxidizing to moderately reducing conditions (Re-ReO2 to Co-CoO and graphite buffers), to < 1 at the most reducing conditions (Fe-FeO buffer). D S n I l m / m e l t exhibits a variation trend similar to D S n T t n / m e l t but is always lower than D S n T t n / m e l t at a given fO2. These D S n m i n / m e l t values can be applied to quantitatively assess the mineralization potential of granitic magmas. Using D S n T t n / m e l t , we estimate that Sn contents are ~150–400 ppm in the pre-mineralization magmas of the tin-mineralized Qitianling plutons (South China). [ABSTRACT FROM AUTHOR]

In this study, a novel approach for the environmentally conscious extraction of titanium dioxide from ilmenite ore while limiting the environmental impact and enhancing the advantage from an economic process. Leaching conditions were tested with different acids for effective separation of the TiO2 and were optimized concerning different experimental parameters. TiO2 and TiO2NPs were characterized using with different tools. Catechol polyurethane foam immobilized with TiO2NPs was prepared and its antimicrobial action was tested against Gram-negative bacterium E. coli, Gram-positive bacterium B. cereus, and fungus A. niger. CAT-PUF /TiO2NPs showed antimicrobial effect against E. coli, B. cereus, and A. niger with inhibition zones of 27 ± 0.14, 12 ± 0.14, and 22 ± 0.06 mm, respectively. Incorporating bioinformatics, this research contributes to the burgeoning field of nanotechnology-enabled antimicrobial materials, offering insights into the potential applications of CAT-PUF/TiO2NPs in combating microbial threats. Through bio-informatics tools, the potential toxicity of the synthesized nanoparticles was assessed, providing valuable insights into their safety profile and environmental impact. Furthermore, simulating the binding affinity between the nanoparticles and target biomolecules, such as cell membrane proteins or enzyme receptors, this aspect of the research sheds light on the mechanistic underpinnings of their antimicrobial efficacy. [ABSTRACT FROM AUTHOR]

The commercialization of the photocatalysis technology requires that the synthesis of the photocatalytic material is easy to scale up. Thus, the synthesis from earth‐abundant minerals represents one plausible solution to obtain materials by a scalable process with a lower environmental impact. So far, the most promising photocatalyst for this application is titanium dioxide (TiO2), which can be obtained from ilmenite ore; however, its synthesis usually implies toxic solvents and complicated reaction conditions. Thus, here is proposed an optimized method to extract higher amounts of TiO2 by a multivariable Plackett‐Burman design of experiments considering the mass of the ore precursor, the addition of phosphoric acid (H3PO4), the digestion temperature, the amount of base to adjust the pH, and the final thermal treatment. From this design, it was possible to minimize the heat treatment and the amount of base used to favor higher TiO2 (rutile) content with the presence of additional phases of iron oxides (Fe2O3) that act as co‐catalyst to enhance the photocatalytic activity. The photocatalytic activity of the TiO2/Fe2O3 composites obtained was investigated in four model reactions to obtain solar fuels (H2 evolution and CO2 reduction) and to remove endocrine water pollutants (bisphenol A and dyeing water), using visible and natural solar irradiation, respectively. [ABSTRACT FROM AUTHOR]

A new thermodynamic model for silicate melt in the Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–TiO2–Fe2O3–Cr2O3 model system is presented, building on the tholeiitic through to granitic melt model of Holland et al. (2018) [Journal of Petrology, 59, 881–900] but extending for the first time into anhydrous alkaline systems. The new melt model is accompanied by new thermodynamic models for nepheline, kalsilite, leucite, melilite and ilmenite. Collectively these models enable pseudosection modelling of alkaline-silicate magmatic systems, providing a new tool for investigating this geologically- and economically-important compositional space. The models are calibrated with respect to experimental data on phase relations among minerals and melt, and the fit is benchmarked here via detailed comparison with seven experimental datasets, which encompass a range of pressure (0–22 kbar), temperature (680–1350°C), oxygen fugacity (log f O2 ΔFMQ-3 to +1), total alkali (3–16 wt %) and silica (37–70 wt %) conditions. The calculated pseudosections successfully reproduce experimental crystallisation sequences and phase compositions, indicating that the thermodynamic models are well calibrated across this spectrum of conditions. Redox buffered experimental conditions are simulated using oxygen buffered pseudosections. Contouring of oxygen buffered pseudosections with X Fe3+ (mol. Fe3+/Fetotal), or pseudosections of varying X Fe3+ with ΔFMQ, reveals (i) often complex and non-intuitive relationships between these two representations of oxidation state, and (ii) substantial variation in ferric iron over narrow temperature intervals in some oxygen buffered sets of experiments. An implication is that simulating oxygen buffering is vital when benchmarking thermodynamic models using experimental results. Furthermore, because natural igneous systems likely feature a near-constant X Fe3+, it is important to assess experimental results in this framework when making inferences about natural systems, recognising that oxygen fugacity is a consequence not a control of phase equilibria in nature. Overall, our new models provide a novel tool to explore the role of variables, such as pressure, fractional crystallisation and crustal assimilation in the petrogenesis of alkaline-silicate magmatic systems and their associated mineralisation. [ABSTRACT FROM AUTHOR]

In addition to bubble–particle interaction, particle–particle interaction also has a significant influence on mineral flotation. Fine particles that coat the mineral surface prevent direct contact with collectors and/or air bubbles, thereby lowering flotation recovery. Calculating the particle interaction energy can help in evaluating the interaction behavior of particles. In this study, the floatability of coarse ilmenite (−151 + 74 μm) and different particle sizes (−45 + 25, −25 + 19, −19 μm) of forsterite with NaOL as a collector was investigated. The results showed that forsterite sizes of −45 + 25 and −25 + 19 μm had no effect on the ilmenite floatability, whereas −19 μm forsterite significantly reduced ilmenite floatability. A particle size analysis of artificially mixed minerals and a scanning electron microscopy (SEM) analysis of the flotation products showed that heterogeneous aggregation occurred between ilmenite and −19 μm forsterite particles. The extended DLVO (Derjaguin–Landau–Verwey–Overbeek) theory was applied to calculate the interaction energy between mineral particles using data from zeta potential and contact angle measurements. The results showed that the interaction barriers between ilmenite (−151 + 74 μm) and forsterite (−45 + 25, −25 + 19, and −19 μm) were 11.94 × 103 kT, 8.23 × 103 kT and 4.09 × 103 kT, respectively. Additionally, the interaction barrier between forsterite particles smaller than 19 μm was 0.51 × 103 kT. The strength of the barrier decreased as the size of the forsterite decreased. Therefore, fine forsterite particles and aggregated forsterite can easily overcome the energy barrier, coating the ilmenite particle surface. This explains the effect of different forsterite sizes on the floatability of ilmenite and the underlying mechanism of particle interaction. [ABSTRACT FROM AUTHOR]

Ediacaran–Cambrian magmatism in the Central Subprovince (Borborema Province, NE Brazil) generated abundant A-type granites. This study reviews published whole-rock and mineral chemistry data from thirteen Ediacaran–Cambrian A-type intrusions and a related dike swarm. It also presents new mineral chemistry and whole-rock data for one of these intrusions, along with zircon trace element data for five of the intrusions. Geochronological data from the literature indicate the formation of these A-type intrusions during a 55 Myr interval (580–525 Ma), succeeding the post-collisional high-K magmatism in the region at c. 590–580 Ma. The studied plutons intruded Paleoproterozoic basement gneisses or Neoproterozoic supracrustal rocks. They are ferroan, metaluminous to peraluminous and mostly alkalic–calcic. The crystallization parameters show pressure estimates mainly from 4 to 7 kbar, corresponding to crustal depths of 12 to 21 km, and temperatures ranging from 1160 to 650 °C in granitoids containing mafic enclaves, and from 990 to 680 °C in those lacking or containing only rare mafic enclaves. The presence of Fe-rich mineral assemblages including ilmenite indicates that the A-type granites crystallized under low ƒO2 conditions. Zircon trace element analyses suggest post-magmatic hydrothermal processes, interpreted to be associated with shear zone reactivation. Whole-rock geochemical characteristics, the chemistry of the Fe-rich mafic mineral assemblages, and zircon trace elements in the studied granitoids share important similarities with A2-type granites worldwide. [ABSTRACT FROM AUTHOR]

Due to their high density, the ilmenite-bearing cumulates (IBC) (with or without KREEP) formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar mantle overturn. Geophysical evidence implied that IBC may descend deep inside the Moon and remain as a partially molten layer at the core-mantle boundary (CMB). However, partial melting may have occurred on the mixed mantle cumulates during the sinking of IBC/KREEP and the silicate melt may be positively buoyant, thus preventing the IBC/KREEP layer from sinking to the CMB. Here, we perform thermodynamic simulation on the stability of lunar mantle cumulates at different depths mixed with different amounts of IBC/KREEP from an updated LMO model. The modeling results suggest that the sinking of IBC/KREEP will cause at least 5 wt% partial melting in the shallow (~ 120 km) and a much larger degree of partial melting in the deep lunar mantle (~ 420 km). Due to the density contrast with the surrounding mantle, IBC/KREEP-bearing melts could potentially decouple under certain conditions. The modified lunar mantle by sinking of IBC/KREEP can better explain the formation of different kinds of lunar basaltic magma than the primary lunar mantle formed through differentiation of lunar magma ocean. Sinking of IBC/KREEP back into the lunar mantle may introduce plagioclase, clinopyroxene, garnet, and incompatible radioactive elements into the deep lunar mantle, which will further affect the thermal and chemical evolution of the lunar interior. [ABSTRACT FROM AUTHOR]

The paper reports comprehensive petrological, geochemical and mineralogical studies of osumilite-bearing andesite-dacitic lavas of Kordieritoviy Volcano (Keli Highland, Greater Caucasus) erupted at the end of the Pleistocene (about 200 ka). The petrographic and microprobe analysis showed that the rocks contain three paragenetic mineral associations: (1) "xenogenic" (metamorphic) association consisting of garnet (XPrp = 0.42, XAlm = 0.51–0.53, XGrs = 0.04–0.05) + hercynite + sapphire + bronzite + pargasite + ilmenite; (2) early magmatic association represented by hypersthene + hercynite + garnet (XPrp = 0.21–0.31, XAlm = 0.52–0.71, XGrs = 0.04–0.13) + ferro-kaersutite + ilmenite; (3) late magmatic association including hypersthene-ferrohypersthene + labradorite + garnet (XPrp = 0.04–0.14, XAlm = 0.65–0.81, XGrs = 0.06–0.18) + osumilite-(Mg) + phlogopite + tridymite + ilmenite + apatite. The osumilite-(Mg) (phenocrysts, xenomorphic aggregates in the rock matrix, and crystals in miarolic cavities), the average formula for dacites of Kordieritoviy Volcano can be written as (K0.73Na0.06Ca0.02 )1.00(Mg1.06 Mn0.04)2.00(Al2.75 Ti0.01)3.00(Si10.34Al1.66)12O30, formed mainly at late magmatic stages – in intermediate chambers immediately prior to the rise of the melt to the surface or after its eruption. Accordingly, this mineral in the studied lavas has a purely magmatic origin. Thermobarometric calculations and petrological modeling showed that the deep magma chamber of Kordieritoviy Volcano was located at a depth of 45–53 km near the Moho discontinuity. The temperature of the melt at the early magmatic stage was no less than 1100°C at 17–23 kbar. Crystallization of osumilite-(Mg) in intermediate magmatic chambers (at depths of 30–40 km) and during the lava ejection occurred at 1030–870°C and pressure progressively decreasing from 14–9 to 1 kbar. A petrogenetic model has been proposed to explain the genesis of exotic osumilite-bearing lavas of Kordieritoviy Volcano. It includes several stages: (1) formation of an enriched upper-mantle source (lithospheric mantle metasomatized by permanent interaction at the Moho discontinuity with the overlying lower crust composed of metamorphosed terrigenous-volcanogenic complexes); (2) generation of "dry" basaltic magmas in the source; (3) crystallization differentiation in the source (fractionation of olivine and chromium spinels) with the formation of a "dry" overheated andesitic melt; (4) limited-scale assimilation of the lower crustal material made up of leucocratic granulites by highly differentiated andesitic melts rising to the surface, with simultaneous fractionation of garnet, orthopyroxene and ilmenite from the melt. [ABSTRACT FROM AUTHOR]

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This article presents the results of a thermodynamic analysis of the oxidation soda conversion reactions of minerals in ilmenite concentrates in the temperature range of 373–2273 K. The thermodynamic parameters of pseudorutile, pseudobrukite, and the new minerals, zhikinite and spessartine, were calculated for the first time. It has been established that the most important criterion relating to the stability of titanium minerals and related elements, as well as the reaction properties of the structural oxides of metals and silicon, is their degree of oxidation. Oxides of silicon (IV) and manganese have the best reactivity in solid-phase oxidizing alkaline environments (VI). Modeling this process scientifically substantiates the mechanism involved in the destruction of minerals in ilmenite concentrates in the low-temperature region in the presence of atmospheric oxygen and sodium oxide of soda ash, which are decomposed through the absorption of heat and the evaporation of moisture during the dehydration of hydrated minerals of iron and manganese and the dehydration of the soda–ilmenite batch. Tests conducted during pilot metallurgical production at the Institute of Metallurgy and Enrichment (PMP of JSC) confirmed the feasibility of processing high-chromium and siliceous rutile leucoxene ilmenite concentrates, which are unsuitable for traditional pyro- and hydro-metallurgical enrichment methods, through single-stage oxidation soda roasting, followed by the leaching of easily soluble sodium salts of iron and associated impurities with water and a dilute hydrochloric acid solution. The proposed energy-saving method ensures the production of high-purity (>98%) synthetic rutile while eliminating the formation of strong deposits on the lining of roasting units. [ABSTRACT FROM AUTHOR]

In this study, the reduction kinetics of ilmenite concentrate from a domestic mine (Kahnuj, Kerman, Iran) in pure hydrogen in the temperature range of 500 °C to 1100 °C was investigated. From the non-isothermal reduction results corresponding kinetic parameters for the as-received and pre-oxidized concentrates were calculated using the Coats-Redfern method. The reduction process in both raw and pre-oxidized ilmenite, at 800 °C was controlled by diffusion through the product layer. The kinetic analysis for ilmenite pre-oxidized at 1000 °C indicated that the reduction process followed a chemical reaction and nucleation and growth mechanism. The samples pre-oxidized at 800 °C and 1000 °C exhibited higher mass loss values and reduction degrees compared to the raw ilmenite. The promoting effect of pre-oxidation on the reduction of ilmenite is attributed to the phase changes in pre-oxidized ilmenite and the porous structure created during the reduction process after the pre-oxidation process. X-ray diffraction (XRD) patterns confirmed the presence of pseudorutile, rutile, and hematite after oxidation at 800 °C, and pseudobrookite and rutile were stable phases after oxidation at 1000 °C. [ABSTRACT FROM AUTHOR]

Due to the similar physical and chemical properties of ilmenite and olivine, separating them is challenging. The flotation process, with the use of collectors, is an effective method. In this study, a ternary collector consisting of aluminum ion (III), benzohydroxamic acid (BHA), and sodium oleate (NaOL) was prepared for the flotation separation of ilmenite and olivine. Through micro-flotation experiments, molecular dynamics simulation (MD), density functional theory (DFT), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis, the synergistic effect between the components of the ternary collector and the adsorption configuration on the surface of ilmenite was investigated. The results revealed that at pH = 8, Al (III), BHA, and NaOL could coordinate and adsorb effectively on the surface of ilmenite, enhancing its floatability for separation from olivine. The adsorption configuration differed from previous reports, showing a co-adsorption of multiple forms on the surface of ilmenite. [ABSTRACT FROM AUTHOR]

Type II chondrules have higher oxidation states than type I chondrules; in ordinary chondrites (OC), type II chondrules tend to be larger, richer in bulk Fe, and have higher densities than type I chondrules. Magnesian type IA chondrules tend to be richer in 16O than type II chondrules. Because the aerodynamic behavior of a particle is a function of the product of its size and density, type I and type II chondrules (or their precursors) were partly separated in the ordinary chondrite zone of the solar nebula prior to the accretion of OC parent asteroids. LL chondrites acquired a chondrule population with the highest type II/type I ratios, L chondrites acquired chondrules with an intermediate ratio, and H chondrites acquired chondrules with the lowest type II/type I ratios. This contributed to the observed differences among OC groups in oxidation state and O‐isotopic composition: in going from H to L to LL, mean oxidation state increases and mean Δ17O values increase. Higher oxidation is marked by increases in the FeO contents of olivine, low‐Ca pyroxene, chromite, and ilmenite; increases in the TiO2 content of chromite; and increases in the Co content of kamacite. [ABSTRACT FROM AUTHOR]

Akimotoite, ilmenite-type MgSiO3 high-pressure polymorph can be stable in the lower-mantle transition zone along average mantle and subducting slab geotherms. Significant amounts of Al2O3 can be incorporated into the structure, having the pyrope (Mg3Al2Si3O12) composition. Previous studies have investigated the effect of Al2O3 on its crystal structure at nearly endmember compositions. In this study, we synthesized high-quality ilmenite-type Mg3Al2Si3O12 phase at 27 GPa and 1073 K by means of a Kawai-type multi-anvil press and refined the crystal structure at ambient conditions using a synchrotron X-ray diffraction data via the Rietveld method to examine the effect of Al2O3. The unit-cell lattice parameters were determined to be a = 4.7553(7) Å, c = 13.310(2) Å, and V = 260.66(6) Å3, with Z = 6 (hexagonal, R 3 ¯ ). The volume of the present phase was placed on the akimotoite-corundum endmember join. However, the refined structure showed a strong nonlinear behavior of the a- and c-axes, which can be explained by Al incorporation into the MgO6 and SiO6 octahedral sites, which are distinctly different each other. Ilmenite-type Mg3Al2Si3O12 phase may be found in shocked meteorites and can be a good indicator for shock conditions at relatively low temperatures of 1027–1127 K. [ABSTRACT FROM AUTHOR]

Ilmenite (Fe2+TiO3) and geikielite (MgTiO3) are important terrestrial minerals relevant to the geology of the Earth, the Moon, Mars, and meteorite samples. Raman spectroscopy is a powerful technique that allows for mineral cation determination for the ilmenite-geikielite solid solution. We report on a suite of nine samples within the ilmenite-geikielite solid solution and provide context for their quantitative interpretation. We compare a univariate Raman peak position model for predicting ilmenite composition with a multivariate machine learning model. The univariate model is currently recommended, though the multivariate model may become superior if the data set size is increased. This study lays the groundwork for quantifying Fe (ilmenite) and Mg (geikielite) within oxide minerals using a cheap, portable, and efficient technology like Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Based on the difficulty of extracting titanium from ilmenite, this study modified ilmenite by alkali roasting to improve the leaching rate of titanium. The leaching behaviour and kinetics of titanium in pretreated slag and the mechanism of limiting titanium leaching were studied. The results indicate that alkaline roasting pre-treatment of the ilmenite ore can transform acid-resistant FeTiO3 into more reactive Na2TiO3 and NaFeO2, which are more amenable to leaching. Simultaneously, under the following pre-treatment conditions—a sodium hydroxide to ilmenite ore mass ratio of 1.5:1, roasting temperature of 1123.15 K and roasting time of 1 h—the optimal leaching conditions are found to be a leaching temperature of 363.15 K, sulphuric acid mass fraction of 60% and liquid–solid mass ratio of 6:1. Under these conditions, the titanium extraction was most efficient, achieving a titanium leaching rate of 97.36%. The leaching reaction of titanium in the pre-treated slag follows the shrinking core model of the internal diffusion-controlled step. The apparent activation energy for the leaching reaction is determined to be 77.45 kJ/mol. Analysis through XRD, XPS and SEM–EDS reveals the formation of silica gel during leaching, which also has an adsorption effect, preventing complete titanium leaching. [ABSTRACT FROM AUTHOR]

Chemical looping combustion is a highly efficient CO2 separation technology without direct contact between combustion air and fuel. A metal oxide is used as an oxygen carrier in dual fluidized beds to generate clean CO2. The use of biomass is the focus of current research because of the possibility of negative CO2 emissions and the utilization of biogenic carbon. The most commonly proposed OC are natural ores and residues, but complete combustion has not yet been achieved. In this work, the direct utilization of CLC exhaust gas for methane synthesis as an alternative route was investigated, where the gas components CO, CH4 and H2 are not disadvantageous but benefit the reactions in a methanation step. The whole process chain, the coupling of an 80 kWth pilot plant with gas cleaning and a 10 kW fluidized bed methanation unit were for this purpose established. As OC, ilmenite enhanced with limestone was used, combusting bark pellets in autothermal operation at over 1000 °C reaching high combustion efficiencies of up to 91.7%. The fuel reactor exhaust gas was mixed with hydrogen in the methanation reactor at 360 °C and converted with a methane yield of up to 97.3%. The study showed especially high carbon utilization efficiencies of 97% compared to competitor technologies. Based on the experimental results, a scale-up concept study showed the high potential of the combination of the technologies concerning the total efficiency and the adaptability to grid injection. [ABSTRACT FROM AUTHOR]

Abstract In this study, a novel approach for the environmentally conscious extraction of titanium dioxide from ilmenite ore while limiting the environmental impact and enhancing the advantage from an economic process. Leaching conditions were tested with different acids for effective separation of the TiO2 and were optimized concerning different experimental parameters. TiO2 and TiO2NPs were characterized using with different tools. Catechol polyurethane foam immobilized with TiO2NPs was prepared and its antimicrobial action was tested against Gram-negative bacterium E. coli, Gram-positive bacterium B. cereus, and fungus A. niger. CAT-PUF /TiO2NPs showed antimicrobial effect against E. coli, B. cereus, and A. niger with inhibition zones of 27 ± 0.14, 12 ± 0.14, and 22 ± 0.06 mm, respectively. Incorporating bioinformatics, this research contributes to the burgeoning field of nanotechnology-enabled antimicrobial materials, offering insights into the potential applications of CAT-PUF/TiO2NPs in combating microbial threats. Through bio-informatics tools, the potential toxicity of the synthesized nanoparticles was assessed, providing valuable insights into their safety profile and environmental impact. Furthermore, simulating the binding affinity between the nanoparticles and target biomolecules, such as cell membrane proteins or enzyme receptors, this aspect of the research sheds light on the mechanistic underpinnings of their antimicrobial efficacy.

This is an article in the field of ceramics and composites. Taking ilmenite ore as the research object, the possible phase transformation of FeTiO3 in concrete liquid phase environment was analyzed in order to provide a basis for the utilization of ilmenite tailings. The thermodynamic stability of ilmenite (FeTiO3) was analyzed by thermodynamic calculation. Ilmenite ore powder was soaked in simulated concrete pore solution at 20 ℃ and 80 ℃ for 28 d and 270 d, XRD and SEM/EDS were used to detect mineral transformation. Using ilmenite ore to replace part of the gravel to prepare concrete, the influence on concrete strength at 20 ℃ and 80 ℃ was studied respectively. The results of thermodynamic calculations show that FeTiO3 is unstable in the environment of O2 and converts into Fe3O4 or Fe2O3 and TiO2. The immersion experiment of ilmenite in the simulated concrete pore solution shows that ilmenite has no obvious changes. The concrete strength test shows that at 20 ℃ and 80 ℃, when ilmenite ore replaces 5% crushed stone, the compressive strength of concrete increases, and when the replacement is 15%, the compressive strength decreases, the reason is that the quartz in the ilmenite ore has undergone an alkali aggregate reaction.

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]

Akimotoite, ilmenite-type MgSiO3 high-pressure polymorph can be stable in the lower-mantle transition zone along average mantle and subducting slab geotherms. Significant amounts of Al2O3 can be incorporated into the structure, having the pyrope (Mg3Al2Si3O12) composition. Previous studies have investigated the effect of Al2O3 on its crystal structure at nearly endmember compositions. In this study, we synthesized high-quality ilmenite-type Mg3Al2Si3O12 phase at 27 GPa and 1073 K by means of a Kawai-type multi-anvil press and refined the crystal structure at ambient conditions using a synchrotron X-ray diffraction data via the Rietveld method to examine the effect of Al2O3. The unit-cell lattice parameters were determined to be a = 4.7553(7) Å, c = 13.310(2) Å, and V = 260.66(6) Å3, with Z = 6 (hexagonal, R3¯). The volume of the present phase was placed on the akimotoite-corundum endmember join. However, the refined structure showed a strong nonlinear behavior of the a- and c-axes, which can be explained by Al incorporation into the MgO6 and SiO6 octahedral sites, which are distinctly different each other. Ilmenite-type Mg3Al2Si3O12 phase may be found in shocked meteorites and can be a good indicator for shock conditions at relatively low temperatures of 1027–1127 K.

Geometrization of the deposit consists in collecting, systematizing and using statistical methods to analyze and establish relationships between various characteristics of solid minerals. This approach makes it possible to better understand the conditions of extraction and further processing of mineral raw materials by graphical display of information. Aspects such as the location of deposits, their size, shape, structure, composition of minerals and mining and geological conditions of production are considered. The study of the spatial distribution of harmful and useful elements allows a better understanding of geochemical processes occurring in the earth's crust, as well as predicting the quality of ore and determining the possibility of its use for industrial purposes. The main result of the research is the creation of complex models of placers, which help clarify the structure and conditions of deposit formation, identify conventional and low-productivity areas. A relationship between the distribution of ilmenite and the thickness of the ventilation crust was established. As a result, data were provided for determining optimal mining directions and mineralization zones were identified.

The Ghansura Rhyolite Dome (GRD) is an integral part of the Bathani volcano-sedimentary sequence (BVSs), which in turn is a vital component of the Chotanagpur Granite Gneiss Complex (CGGC), eastern India. The rhyolite dome represents a shallow-level felsic magma chamber that underwent intrusion by basaltic magma during its evolution. The rocks present in the felsic dome such as basalts, rhyolites, and intermediate hybrid rocks preserve evidence of magma mixing and mingling. The objective of this contribution is to take into account, for the first time, that magma mixing processes can play an important role in the generation of calcite in magmatic rocks. The present study focuses on the mingled rocks exposed within the rhyolite dome. Previous reports have documented the existence of two distinct zones (mafic and felsic) interfacing each other in the mingled rocks of the rhyolite dome. The mafic zones dominantly consist of mineral phases such as actinolite, hornblende, biotite, plagioclase, ilmenite, calcite, and titanite. The felsic zones comprise quartz, K-feldspar, plagioclase, and biotite. When mafic magma intruded into the felsic magma chamber, interaction between the mafic and felsic magmas caused diffusion of H, Al, and K ions from the felsic to the mafic endmember. Such diffusive activities resulted in the breakdown of augite, already crystallized in the mafic magma, to form newer minerals like actinolite, hornblende, biotite, calcite, and ilmenite. The presence of ilmenite in the mingled rocks indicates the prevalence of reducing conditions during magma interaction and evolution. Breakdown of hornblende to biotite in such a reduced environmental condition led to the formation of calcite in the mingled rocks. From the results presented in this work, we are proposing that magma mixing can be a viable mechanism to form calcite in igneous rocks by magmatic processes.

The community in Central Bangka Regency carried out an increase in illegal mining in 2021, which could potentially threaten the loss of strategic natural resources. Rocking table miners in Central Bangka Regency produce zircon sand, tin sand, monazite, ilmenite, and tailings, which are potential natural resources containing rare earth metal elements. This research aims to analyze the radioactive content of the minerals zircon sand, tin sand, monazite, ilmenite, and tailings as a threat to human health. The research showed that monazite samples from all villages still had a lot of rare earth metals in them, like yttrium (Y), lanthanum (La), cerium (Ce), samarium (Sm), neodymium (Nd), and gadolinium (Gd). The test results showed that monazite had the highest average concentrations of Rare Earth Elements (REEs), with values of 10.27±3% for La, 12.15±3% for Ce, 24.40±3% for Sm, 7.37±3% for Nd, and 0.69±3% for Gd. For tin samples, the average (Ce) was 2.79±3%, zircon samples had an average (Ce) of 4.33±3%, and (Nd) 1.04±3%. In the ilmenite samples, the average value (Y) was 6.64 ± 3%. Monazite has the most rare earth metal elements, but it has a very low selling price. Monazite plays a crucial role in safeguarding and preventing the loss of strategic natural resources and health threats. It provides policy advice to related institutions through various roles and functions, including investigation, early prevention, and forecasting of these threats.

Abstract A high-density water-based drilling fluid (WBDF) is crucial for maintaining wellbore stability, controlling formation pressures, and optimizing drilling performance in challenging subsurface conditions. In the present research, the effect of micronized calcium carbonate (calcite), extracted from the Aruma formation outcrop, is evaluated as one of the additives that could be added to the ilmenite-weighted WBDF to enhance and optimize its properties. Various concentrations of Calcite microparticles were introduced into identical fluid formulations to assess their impact. The concentrations ranged from 0, 10, 20, to 30 lb/bbl, providing a comprehensive examination of the effects of calcite microparticles across a spectrum of concentrations within the fluid. The results highlighted that adding Barite microparticles to the WBDF revealed a notable enhancement in rheological properties. Specifically, the yield point demonstrated an increase of 37%, 37%, and 11% for concentrations of 10, 20, and 30 lb/bbl of calcite, respectively. Equally significant, high-pressure-high-temperature (HPHT) filtration analysis indicated a considerable enhancement for the fluids containing calcite microparticles. A reduction of 14.5%, 24.6%, and 13% were observed in HPHT filtrate for concentrations of 10 lb/bbl, 20 lb/bbl, and 30 lb/bbl respectively. Simultaneously, there is a reduction in filter cake thickness by 20%, 40%, and 20%, respectively. No ilmenite settling was observed in the sample containing 20 lb/bbl of calcite, unlike the other concentrations. These diverse results strongly suggest that the optimal concentration for calcite microparticles is 20 lb/bbl. The combined utilization of the optimal concentration of calcite microparticles alongside the established additives proves to be an effective strategy for optimizing the ilmenite-weighted WBDF performance in terms of both thermal stability and rheological behavior.

Minerals containing TiO2 are common in Indonesia, such as ilmenite in iron sand deposits scattered along the country's coasts. Ilmenite is an important source of titanium. One method for making TiO2 from ilmenite is by solubilizing both the Fe and Ti elements in HCl and then immediately hydrolyze the Ti. The leaching of low-grade ilmenite (ground to 0.177-0.149 mm) is studied kinetically by HCl in a stirred reactor. The research was conducted using the caustic fusion method followed by HCl leaching. The leaching reaction kinetics at the optimum conditions are analyzed using response surface methodology (RSM) with a second-order polynomial equation model and SSE with the shrinking core model (SCM). The results showed that HCl concentration and leaching time were directly proportional to the leached titanium concentration. In contrast, the leaching temperature was inversely proportional. The optimum operating conditions were obtained at a temperature of 30 °C, 9 M HCl, and 120 min of leaching time. The shrinking core model is a better representation of the kinetics than RSM with a second-order polynomial equation model. Based on SCM, the rate of the leaching reaction of titanium from low-grade ilmenite is controlled by diffusion through the ash layer.

Perchlorate and chlorate are present in various extraterrestrial celestial bodies throughout the solar system, such as Mars, the moon, and asteroids. To date, the origin mechanisms of perchlorate and chlorate on the Martian surface have been well-established; however, relatively little attention has been cast to airless bodies. Here, we experimentally investigated the potential oxidation mechanisms of chloride to chlorate and perchlorate, such as ultraviolet irradiation under H2O- and O2-free conditions and mechanical pulverization processes. Individual minerals, olivine, pyroxene, ilmenite, magnetite, TiO2 and anhydrous ferric sulfate, and lunar regolith simulants (low Ti, CLRS-1; high-Ti, CLRS-2) and their metallic iron (Fe0) bearing counterparts were examined. We found that pulverization of dry matrix material-halite mixtures, even in the presence of O2, does not necessarily lead to perchlorate and chlorate formation without involving water. Under photocatalytic and H2O- and O2-free conditions, olivine and pyroxene can produce oxychlorine (ClOx−) species, although the yields were orders of magnitude lower than those under Martian-relevant conditions. Nanophase-Fe0 particles in the lunar regolith and the common photocatalyst TiO2 can facilitate the ClOx− formation, but their yields were lower than those with olivine. The oxides ilmenite and magnetite did not efficiently contribute to ClOx− production. Our results highlight the critical role of H2O in the oxidation chloride to chlorate and perchlorate, and provide essential insights into the environmental influence on the formation of oxychlorine species on different celestial bodies. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are fluorinated and refractory pollutants that are ubiquitous in industrial wastewater. Photocatalytic destruction of such pollutants with catalysts such as TiO2 and ZnO is an attractive avenue for removal of PFAS, but refined forms of such photocatalysts are expensive. This study, for the first time, utilized milled unrefined raw mineral ilmenite, coupled to UV-C irradiation to achieve mineralization of the two model PFAS compounds perfluorooctanoic acid (PFOA) and perfluoro octane sulfonic acid (PFOS). Results obtained using a bench-scale photocatalytic reactor system demonstrated rapid removal kinetics of PFAS compounds (>90% removal in less than 10 h) in environmentally-relevant concentrations (200–1000 ppb). Raw ilmenite was reused over three consecutive degradation cycles of PFAS, retaining >80% removal efficiency. Analysis of degradation products indicated defluorination and the presence of shorter-chain PFAS intermediates in the initial samples. End samples indicated the disappearance of short-chain PFAS intermediates and further accumulation of fluoride ions, suggesting that original PFAS compounds underwent mineralization due to an oxygen-radical-based photocatalytic destruction mechanism induced by TiO2 present in ilmenite and UV irradiation. The outcome of this study implies that raw ilmenite coupled to UV-C is suitable for cost-effective reactor operation and efficient photocatalytic destruction of PFAS compounds. [ABSTRACT FROM AUTHOR]

This article takes a low grade ilmenite in the western Sichuan region as the research object. In response to the low grade, complex mineral composition, close symbiotic relationship between valuable minerals, and fine embedded particle size of the ilmenite, a magnetic flotation mixed separation process was used to beneficiate ilmenite. Through the experimental study, the beneficiation process and regime of agent are optimized, which provides theoretical basis and technical support for the development and utilization of low grade ilmenite. The experimental results show that magnetic flotation combined process performed excellent effect on the ilmenite ores with TiO2 grade of 7. 45%, and titanium concentrate with TiCO2 grade of 42. 6% and recovery of 77. 51% can be obtained by using a highly selective carboxylic acid collector TOH. [ABSTRACT FROM AUTHOR]

The article presents information on the geological structure and ore content of the Trostyanytsky ilmenite deposit located in the northern part of the Volodarsk-Volynskyi massif of the Korostensky pluton bedrock. The deposit is localized in the weathering crust of the basement crystalline rocks and continental deluvial-alluvial and alluvial sediments of the Middle Jurassic-Lower Cretaceous, which were formed by erosion and redeposition of eluvium. Weathering crust together with deluvial-alluvial and alluvial sediments formed the productive deposits of the Trostyanytsky deposit. On the basis of the created target database containing conditional coordinates of wells, their description and testing results, mapping constructions (isohypses of the roof, sole, isopachites of the thickness of the weathering crust of crystalline rocks of the basement, alluvial sands and redeposited kaolins of the Middle Jurassic-Lower Cretaceous) were carried out; lateral distribution of the average ilmenite content in the weathering crust, in the Middle Jurassic-Lower Cretaceous fluvial deposits and productive sediments, distribution ilmenite content in the vertical section of wells). These mapping constructions were created based on the results of preliminary (1999) and detailed (2008) geological exploration. The direction and strength of correlations between the topography of the sole and the surface, topography of the sole and the thickness of ilmenite-bearing formations, sole relief and ilmenite content, sediment thickness and ilmenite content in the weathering crust, alluvial deposits of the Middle Jurassic-Lower Cretaceous and in productive deposits. The obtained results made it possible to clarify the structural and material parameters of the ore-bearing rocks, the lateral and vertical distribution of ore bearing in different genetic and different age’s formations. [ABSTRACT FROM AUTHOR]

The article provides generalized data on the geological structure, the results of laboratory analyzes of the heavy fraction of the main placer-forming minerals of the Vovchansk zircon-rutile-ilmenite deposit, which was being developed by Demurinsky Mining and Processing Plant LLC in 2002. The geological structure of the Vovchansk deposit includes a complex of Precambrian rocks of the crystalline basement, the Paleozoic-Cenozoic weathered crust, the Paleozoic-Cenozoic sediments, and Quaternary deposits. The industrial concentration of heavy minerals is confined to the middle and upper parts of the Middle Sarmatian subsuite of the Neogene, composed of fine-grained, essentially quartz sands, with a total thickness of 0.4 to 63 m. The content of heavy minerals in the ore-bearing horizon of the deposit ranges from 93.8 to 485 kg/m³ (ilmenite from 37.6 to 242.6 kg/m³, rutile from 15.9 to 64.6 kg/m³, zircon from 2.9 to 9.4 kg/m³, sillimanite and disthene from 20.4 to 117.5 kg/m³). The content of major and minor elements-impurities in individual minerals of the ore-bearing horizon (178 grains) was determined: ilmenite (18 samples), rutile (40 samples), zircon (35 samples), sillimanite (30 samples), staurolite (25 samples), tourmaline (12 samples), ganite (8 samples), monazite (10 samples). The conducted research clarified the typomorphic features of minerals from the sands of the Vovchansk deposit, established their absolute age and probable original sources. [ABSTRACT FROM AUTHOR]

Avoiding the formation of anosovite phase during the ilmenite reduction process is crucial for the preparation of boiling chloride stove. In this study, the dominant regions of different reduction products of ilmenite in CO-CO2 system and the phase transformation behavior of pure ilmenite in the reduction process were studied by XRD and SEM-EDS analysis. It was confirmed that the reduction of ilmenite (FeTiO3) at < 1150°C went through two stages: the formation of metal iron (Fe) with rutile (TiO2) and metal iron (Fe) with anosovite (Ti3O5). At > 1150°C, the reduction of ilmenite went through two stages: the formation of metal iron (Fe) with pseudobrookite (FeTi2O5) and metal iron (Fe) with anosovite (Ti3O5). As a typical ilmenite resource, Panzhihua ilmenite is used to study the reduction behavior of actual ore in CO-CO2 system. The reaction of forming metal iron (Fe) with pseudobrookite (FeTi2O5) could occur at 1000°C, and magnesium was dissolved in the product during the formation of anosovite. The presence of magnesium reduces the dominant area of metal iron (Fe) with rutile (TiO2), which is not conducive to the reduction of iron. [ABSTRACT FROM AUTHOR]

The results of research on the processing of ilmenite concentrate from the Obukhovskoye deposit are presented in this article. As the concentrate has a high chromium content, the study involved converting the iron into metal and the titanium into slag through the addition of soda. Positive results were obtained during the smelting of the ilmenite concentrate, and a one-stage smelting mode was established. This mode involved an increase in the temperature up to 1700 °C, with a heating step of 10 °C/min and using an argon supply. The holding time at this temperature was 30 min, followed by cooling to 700 °C in argon. The optimal parameters for sintering the non-magnetic fraction with soda and leaching the sinter with water and hydrochloric acid solution were also determined. [ABSTRACT FROM AUTHOR]

The article presents the author’s method of selection of priority areas of Ti-Zr placers using an integral indicator. As you know, the integral indicator is the ratio of the total beneficial effect from the development of the deposit to the total costs of operation, it is calculated as the difference between the value of conventional ilmenite (according to the US Geological Survey) (Mineral Commodity..., 2023) and the cost of obtaining overburden and processing the productive layer. Based on the methodology developed and presented in the article, an experiment was conducted on the data of one of the placer deposits located within the Ukrainian placer sub-province. It is proposed to develop it in small blocks that ensure high productivity, minimal impact on the environment and allow replenishment the mineral and raw material base of the titanium industry of Ukraine. This technique can be used at any deposit of titanium-zirconium ores both in Ukraine and abroad. [ABSTRACT FROM AUTHOR]

Oxidation roasting was proposed to treat the problem of the weak magnetic properties of ilmenite. The effects of roasting temperature, roasting time and cooling method on the results of ilmenite magnetic separation were studied. At the same time, the mechanism of the oxidation roasting process was analyzed by XRD, VSM, SEM-EDS. Determine ilmenite suitable oxidation roasting conditions for roasting temperature 750 °C, roasting time of 20 min, and cooling method of air cooling; at this time, the yield of 96.79% can be achieved in the magnetic field intensity of 238.74 kA/m. The XRD results showed that phase changes in the roasting process occur in the order of ilmenite to hematite and rutile to pseudobrookite. The results of VSM showed that the maximum specific magnetization coefficient of ilmenite increased from 3.25x10-5 m³/kg to 5.58x10-5 m³/kg after roasting, and the magnetic property was enhanced. The results of SEM-EDS showed that the phase transition of ilmenite during the roasting process occurs in a spatial order from the edge of the particles to the interior. [ABSTRACT FROM AUTHOR]

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Hydrogen reduction for low-grade iron is consistent with carbon neutrality, which can promote product and heat recycling, fostering environmentally friendly. This study focuses on comparing fluidized bed and fixed bed reduction to determine the optimal hydrogen reduction process, and investigates the improvement of the reduction process by pre-oxidation treatment for ilmenite. The results show that the fluidized bed increases the reduction degree by 7.4% compared with the fixed bed at 60 min, 950 °C. It enhances the crystal transformation of FeTiO 3 →FeTi 2 O 5 →Fe, and decreases particle size of reduced iron to remain a suitable fluidized state. Pre-oxidation treatment during fluidized bed reduction can promote the reduction process, resulting in an 8% increase in reduction degree at 800 °C for 40 min. The kinetic analysis reveals that the fluidized bed reduction is mixed controlled by interfacial chemical reaction and diffusion, whereas the fixed bed is solely governed by interfacial chemical reaction. Fluidized bed reduction effectively reduces the total activation energy by 36.0 kJ/mol in comparison with fixed bed. Pre-oxidized ilmenite reduces the two controlling processes by 19.2 kJ/mol and 5.3 kJ/mol, respectively, in contrast to raw ilmenite. This work provides an effective reduction method for complex low-grade iron ore and realizes high-efficiency iron reduction with zero carbon emission. [Display omitted] • Fluidized bed reduction can provide the crystal phase changing. • Reduced products in fluidized bed have pits, cracks and pores to promote mass and temperature transfer. • There are various kinetic controlling steps for fluidized and fixed bed reduction. • Pre-oxidation treatment can accelerate reduction process and decrease activation energy. [ABSTRACT FROM AUTHOR]

Given the increasing relevance of lunar activities, the location selection for in situ resource utilisation (ISRU) facilities is necessary for identifying the most suitable configuration duringmission planning. To gather information about the dominant location dependencies, a scenario is established wherein an ISRU product is exported to an orbital depot and its mass costs are used for classification. In the selected scenario, oxygen is produced in an ilmenite reduction plant and subsequently exported to the lunar gateway via an oxygen--hydrogen fuelled launcher operated in a round-trip to refuel oxygen at the lunar surface and hydrogen at the lunar gateway. This showed that the transport cost variations could be avoided entirely or have a recessive influence on the mission's total costs over an extended period of time, such as 20 years. The identification of the top-10 most optimal locations for various resolutions was altered only slightly upon consideration of flight costs as compared to considering only the ISRU factors; this indicates the insignificance of flight cost dependencies for the analysed case. [ABSTRACT FROM AUTHOR]

A high-density water-based drilling fluid (WBDF) is crucial for maintaining wellbore stability, controlling formation pressures, and optimizing drilling performance in challenging subsurface conditions. In the present research, the effect of micronized calcium carbonate (calcite), extracted from the Aruma formation outcrop, is evaluated as one of the additives that could be added to the ilmenite-weighted WBDF to enhance and optimize its properties. Various concentrations of Calcite microparticles were introduced into identical fluid formulations to assess their impact. The concentrations ranged from 0, 10, 20, to 30 lb/bbl, providing a comprehensive examination of the effects of calcite microparticles across a spectrum of concentrations within the fluid. The results highlighted that adding Barite microparticles to the WBDF revealed a notable enhancement in rheological properties. Specifically, the yield point demonstrated an increase of 37%, 37%, and 11% for concentrations of 10, 20, and 30 lb/bbl of calcite, respectively. Equally significant, high-pressure-high-temperature (HPHT) filtration analysis indicated a considerable enhancement for the fluids containing calcite microparticles. A reduction of 14.5%, 24.6%, and 13% were observed in HPHT filtrate for concentrations of 10 lb/bbl, 20 lb/bbl, and 30 lb/bbl respectively. Simultaneously, there is a reduction in filter cake thickness by 20%, 40%, and 20%, respectively. No ilmenite settling was observed in the sample containing 20 lb/bbl of calcite, unlike the other concentrations. These diverse results strongly suggest that the optimal concentration for calcite microparticles is 20 lb/bbl. The combined utilization of the optimal concentration of calcite microparticles alongside the established additives proves to be an effective strategy for optimizing the ilmenite-weighted WBDF performance in terms of both thermal stability and rheological behavior. [ABSTRACT FROM AUTHOR]

This paper presents the influence of adding rinsed ilmenite mud waste (R-MUD) on the microstructure of Portland cement composites, compared to similar composites containing fly ash (FA). The aim of the study is the assessment of the pozzolanic activity of ilmenite mud waste by its impact on the microstructure of the cement matrix in comparison to the undoubted pozzolanic activity of fly ash. The presented test results include pore size distribution, phase composition, pozzolanic activity using thermal analysis, R3 bound water test, and microstructural analysis using scanning electron microscopy (SEM). Tests were performed on mortars cured for up to 360 days. The results presented in this paper have shown that R-MUD has a pozzolanic activity level similar to FA or better, which influences pore size distribution in the composite and its microstructure. During the curing process, the microstructure of composites containing R-MUD became more compact and sealed than those with FA, which might also increase their durability. The results of the R3 tests have proven the pozzolanic activity of R-MUD but its level was lower than FA. R-MUD might be a useful substitute for fly ash, especially given the lack of good-quality fly ash on the market. [ABSTRACT FROM AUTHOR]

The text is a collection of poetic verses by Forrest Gander, titled "From Mojave Ghost." The verses explore themes of self-reflection, grief, language, and the power of art. Gander, a writer and translator, draws on his personal experiences and observations to create evocative and introspective poetry. The collection delves into the complexities of human emotions and the search for meaning in life. [Extracted from the article]

This paper addresses the study of a pillow lava interbedded with Late Albian-Early Cenomanian sediments that crops out in Armintza (Bizkaia, Northern Spain). The lava flow is an alkaline basalt with abundant macrocrysts of clinopyroxene, kaersutite, Ca-rich plagioclase (50-86% An) and ilmenite, which display a variety of textures and complex zoning patterns indicative of open-system magmatic behaviour. Macrocryst cores are likely to be inherited antecrysts that underwent complex processes under deep pre-eruptive conditions (≈ 700-800 MPa). Microcrysts and macrocryst rims formed during magmatic ascent and emplacement at shallower levels (≈ 35 MPa). Hypothetical melts in equilibrium with clinopyroxenes and amphiboles have trace element compositions like metasomatic vein melts containing amphibole, and their patterns overlap with those of the Armintza pillow lava. This suggests a metasomatised lithospheric mantle with amphibole-rich veins as a potential source for the alkaline basaltic melt. It is even conceivable that the Armintza pillow lava and other alkaline volcanic manifestations of the Basque-Cantabrian Basin were part of the same magma plumbing system through which a series of time-limited eruptions of different batches of magma ascended from the lithospheric mantle to the upper crust during the Albian to the Santonian. [ABSTRACT FROM AUTHOR]

Aggregates of ilmenite with varying amounts of rutile, ferropseudobrookite, and pseudorutile in suevites from the Ries impact structure have been analyzed by light microscopy, analytical scanning electron microscopy, electron microprobe analysis, and Raman spectroscopy to constrain their formation conditions. The tens to hundreds of micrometer aggregates comprise isometric ilmenite grains up to 15 μm in diameter that form a foam structure (i.e., smoothly curved grain boundaries and 120° angles at triple junctions). Grains with foam structure show no internal misorientations, indicating a post-impact formation. In contrast, ilmenite grains with internal misorientation occurring in the core of the aggregates are interpreted as shocked remnant ilmenite originating from the target gneisses. They can contain twin lamellae that share a common {11 2 0} plane with the host, and the c-axis is oriented at an angle of 109° to that of the host. Similarly, the new grains with foam structure display up to three orientation domains, sharing one common {11 2 0} plane for each pair of domains and c-axes at angles of 109° and 99°, respectively. This systematic orientation relationship likely reflects a cubic supersymmetry resulting from the transformation of the initial ilmenite upon shock (>16 GPa) to a transient perovskite-type high-pressure phase (liuite), subsequent retrograde transformation to the polymorph wangdaodeite, and then back-transformation to ilmenite. Whereas, the new grains with foam structure formed from complete transformation, the twin domains in the shocked ilmenite are interpreted to represent only partial transformation. Ferropseudobrookite occurs mostly near the rim of the aggregates. An intergrowth of ferropseudobrookite, ilmenite, and rutile, as well as magnetite or rarely armalcolite occurs at contact with the (devitrified) matrix. The presence of ferropseudobrookite indicates high temperature (>1140 °C) and reducing conditions. The surrounding matrix provided Mg2+ to form the ferropseudobrookite-armalcolite solid solution. Rutile can occur within the aggregates and/or along the ilmenite boundaries; it is interpreted to have formed together with iron during the decomposition of ilmenite at lower temperatures (850–1050 °C). We suggest magnetite in the rims formed by electrochemical gradients driven by the presence of a reducing agent, where Fe2+ within ilmenite diffused toward the rim. Subsequent cooling under oxidizing conditions led to the formation of magnetite from the iron-enriched rim as well as pseudorutile around ilmenite grains. Our study demonstrates that the specific crystallographic relationships of ilmenite grains with foam structure indicate a back-transformation from high (shock) pressures >16 GPa; moreover, the presence of associated Fe-Ti-oxides helps indicate local temperature and oxygen fugacity conditions. [ABSTRACT FROM AUTHOR]

This paper discusses the natural radioactivity levels in ilmenite ore and its final product. Two economically viable ores of titanium are ilmenite (FeO.TiO2) and rutile (TiO2). High-purity germanium (HPGe) detector was used to analyse samples of raw ore, its purified fraction and the final product (synthetic rutile). Radioactivity levels due to 238U and 232Th and its daughter products were estimated. The concentration of 238U and 232Th in raw ore, purified ore and synthetic rutile was found to be 204 ± 4 and 1208 ± 5, 89.0 ± 4 and 597.0 ± 4, 119 ± 2.5 and 398.0 ± 3 Bq/kg, respectively. The dose rates due to gamma photons estimated in raw ore and synthetic rutile were 572 nSv/h and 277 nSv/h, respectively. The activity index estimated was 5.3 for raw ore and 2.3 for final product (synthetic rutile). The final product contained only 25% of the radioactivity compared to the ore showing significant reduction in radioactivity due to the processing of the ore. [ABSTRACT FROM AUTHOR]