Clayey materials from two barangays in Talakag, Bukidnon, Philippines, were studied for potential ceramic stoneware products. Twelve site samples were collected and investigated through X-ray Fluorescence analysis to determine physical and firing properties at 1100°C. In terms of chemical oxide content, the studied clays are rich in SiO₂, Al₂O₃, TiO₂, and Fe₂O₃. Physiochemically, results show large particle size variations with medium to low plasticity. Particle size distribution reveals that the average particle size is lower than 425 microns. SiO₂ (24.62-46.54%) and Al₂O₃ (26.85% - 42.10%) are major chemical oxides, followed by TiO₂ (1.42% - 2.78%), Fe₂O₃ (0.531% - 25.46%), and alkali and alkali earth oxides in trace amounts. These results determine their behavior on firing at a specified temperature. The range of color was determined using a portable color meter and shows that a few specimens are predominantly from cream to light cream or are a white color after firing at 1100°C. The linear shrinkage values vary from 1.79% to 25.685, weight loss from 3.15% to 33.40%, and bulk density from 1.23 to 1.77 g/cm³. The water absorption ranges from 13 % to 40.15 % and the apparent porosity ranges from 37% to 62%. The evaluation of the studied clays based on their physicochemical and ceramic properties revealed that they are suitable for the manufacture of ceramic wares such as earthenware tiles and fired brick bodies.

Silicon carbide (SiC), a mineral-derived non-oxide ceramic, has recently gained significant interest as a nanostructured filler for thermal-management materials due to its high thermal conductivity (~490 W·m⁻¹·K⁻¹), chemical stability, wide band gap, and exceptional resistance to oxidation and thermal degradation. When dispersed in polymer matrices, SiC nanostructures function as thermally conductive nodes capable of forming phonon-transport pathways and restricting chain mobility, thereby enhancing heat dissipation and structural robustness. Although several studies have explored SiC-reinforced polymeric systems, systematic comparisons across different host polymers remain limited, particularly with regard to filler-content optimization and thermal response under varying loading conditions. In this work, SiC nanoparticles were incorporated into polypropylene (PP) and polystyrene (PS) matrices at 1–10 wt% via melt blending, enabling evaluation of the influence of nanofiller loading on morphology, crystallization behaviour, and thermal endurance. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) revealed a notable increase in glass transition and decomposition temperatures, confirming improved thermal resistance and molecular confinement at the SiC–polymer interface. SEM further verified uniform filler dispersion at low contents and the development of thermally conductive micro-networks at 5–7 wt%, correlating with enhanced heat-dissipation efficiency. At higher concentrations, partial aggregation was observed, resulting in increased interfacial phonon scattering and reduced thermal transport efficiency relative to the optimum. The results demonstrate that both PP/SiC and PS/SiC nanocomposites show substantial thermal stabilization and improved structural retention, with optimal performance achieved between 5–7 wt%. This work contributes to the expanding field of mineral-reinforced polymer nanocomposites, providing a route toward lightweight, thermally stable materials suitable for electronics packaging, heat-resistant components, and next-generation thermal-management applications.

The Cenozoic plutonic assemblages exposed in northeast Saveh, located within the central segment of the Urumieh–Dokhtar Magmatic Arc (UDMA) in Iran, include monzonite, monzodiorite, gabbro, and gabbrodiorite lithologies. Integrated zircon U-Pb geochronology, Lu-Hf isotopic analysis, and whole-rock geochemistry reveal that these rocks belong to a medium-K calc-alkaline, metaluminous suite with typical arc-related geochemical signatures. Zircon U-Pb ages ranging from ~60 to 3 Ma point to a long-lasting and multi-phase magmatic evolution from the Middle Paleocene to the Middle Pliocene. Contrary to earlier studies suggesting a prolonged magmatic lull between 72–57 Ma, our results indicate a shorter dormancy period (~10–12 Ma). Three major magmatic pulses are identified: in the Late Eocene (~47–40 Ma), Early Miocene (~23–18 Ma), and Late Miocene to Pliocene (~11–5.2 Ma), all reflecting a subduction-related tectonomagmatic setting. The youngest zircon ages (~11–2.5 Ma) from gabbroic units suggest that magmatism continued up to the Pliocene–Pleistocene boundary, likely linked to ongoing subduction processes shaping the Zagros orogen. Zircon εHf(t) values (−11.43 to +12.5) along with geochemical trends indicate magma generation involving fractional crystallization, assimilation of crustal material, and mantle-derived inputs. Crystallization temperatures of clinopyroxene (1150–1200 °C), coupled with trace element data, support a melt source in a metasomatized spinel-bearing lherzolitic mantle at depths shallower than 80 km. This magmatism was likely driven by asthenospheric upwelling and slab rollback, which induced partial melting of the lithospheric mantle and sustained the region’s long-lived magmatic activity.

Silicon carbide (SiC) was synthesized through the carbothermal reduction of mineral-derived silicon dioxide (SiO₂) using an argon-assisted vacuum route, establishing a direct link between natural mineral resources and functional ceramic nanomaterials. The obtained β-SiC nanostructures, with crystallite sizes of 13–44 nm depending on strain relaxation, were incorporated into a polystyrene (PS) matrix (1–10 wt %) to investigate how filler morphology and loading affect the composite’s optical and dielectric behavior. X-ray diffraction confirmed the cubic 3C-SiC phase, while SEM revealed faceted micrograins derived from SiO₂ precursors. FTIR spectra retained the characteristic polymer bands but showed progressive enhancement of Si–O–C and Si–C vibrations, confirming partial surface oxidation typical of mineral-origin SiC. Optical spectroscopy indicated a widening of the band gap from 3.91 to 4.22 eV as SiC concentration increased up to 5 wt %, reflecting improved dispersion and cleaner SiC–PS interfaces. Dielectric spectroscopy revealed a systematic rise in permittivity (ε′) and controlled energy dissipation (ε″) with filler loading, governed by Maxwell–Wagner–Sillars interfacial polarization below percolation. The composite with 7 wt % SiC exhibited the highest crystallinity and minimal internal strain, demonstrating an optimal balance between dielectric stability and optical transparency. This study bridges mineral-based precursor chemistry and polymer nanocomposite design, offering a sustainable route for developing multifunctional dielectric and UV-shielding materials from naturally sourced SiO₂.

Antimony (Sb) is a critical metal and emerging hazardous pollutant, chemically akin to arsenic (As) and widely used as antimonial lead in Pb–Sb–(Sn) alloys. Despite its volatility, ~45–50% of Sb input to municipal solid waste incinerators remains in bottom ash (IBA). Sb leaching, particularly during mineral carbonation, compromises IBA reuse. We report the systematic occurrence of Pb–(Sb)–(Sn) particles in IBA fines (< 2 mm), spanning a continuum of alteration states. When oxidized, these particles display distinctive yellow to brown-reddish colours and were found in all four samples analysed from the ASHES academia–industry innovation program. Crystal chemistry and formation pathways were resolved at the particle scale using SEM-EDS, XRPD, and TEM-EDXS-EELS, confirming the presence of Sb(0), Sb(III), and Sb(V). Carbonation behaviour was assessed by blending Ca(OH)₂ with crushed Pb–(Sb)–(Sn) particles. Carbonation enhances the dissolution of Pb–(Sb)–(Sn) oxides, with Pb reprecipitating as carbonates with calcite, while Sb remains in solution, which explains the inverse Pb–Sb leaching behaviour widely reported. The strong Pb–Sb association has treatment implications, suggesting that density separation of IBA fines prior to carbonation could mitigate Sb release. We propose that this phase is the main source of Sb leaching under IBA weathering conditions, as metallic Pb–Sb assemblages are far less volatile than Sb species in plastics. During incineration, they remain on the grate and partially crystallize, whereas Sb from plastics is more likely to volatilize and be captured in fly ash. Sb partitioning during incineration is thus strongly source-dependent, reflecting the distinct thermal behaviours of its main industrial forms.

This study presents a thermodynamic modeling framework for optimizing phosphorus recovery from wastewater through the crystallization of vivianite Fe₃(PO₄)₂·8H₂O. With phosphorus identified as a critical raw material in the European Union and global phosphate reserves under geopolitical stress, recovering phosphorus from wastewater has become both an environmental and economic priority. The methodology involves constructing a thermodynamic model that integrates heterogeneous chemical equilibria, including hydrolysis, complex formation, ligand protonation, and mineral precipitation. The model evaluates interactions among phosphate, iron(II) ions, and potential complexing agents across a pH range of 7 to 11. Gibbs free energy ∆G^overall changes for the overall crystallization–dissolution process including competing reactions are calculated to define the thermodynamic stability areas for vivianite and co-precipitates such as hydroxyapatite, calcium phosphates, and iron hydroxides. Species distribution diagrams for the analyzed heterogeneous systems and overall Gibbs free energy ∆G^overall stability maps were constructed based on both synthetic and real wastewater compositions. Obtained thermodynamic results show that phosphorus recovery efficiency improves with Fe:P molar ratios between 1.5 and 1.8, with optimal crystallization occurring at pH 7.0 to 7.5. At higher pH values, the formation of competing mineral phases reduces the selectivity for vivianite. The model also provides quantitative predictions of residual phosphate and iron concentrations after the wastewater treatment. The developed thermodynamic framework facilitates improved control of vivianite crystallization parameters and supports nutrient recovery strategies aligned with circular economy principles. This model is adaptable to a range of wastewater types and informs the design of efficient, low-impact phosphorus recovery technologies.

This study presents a thermodynamic framework for predicting synergistic mineral dissolution and buffering in wastewater treatment systems. Buffering is essential for stabilizing wastewater composition against pH fluctuations and ionic disturbances caused by variable chemical inputs. The model addresses multicomponent heterogeneous systems containing both soluble and insoluble species, focusing on key minerals such as struvite and vivianite that play a central role in nutrient recovery and contaminant immobilization. A key innovation of this framework is its ability to describe coupled mineral dissolution and precipitation processes through a unified set of thermodynamic equations. These incorporate mass balance constraints and equilibrium expressions involving metal ion hydrolysis, metal ion–ligand complex formation, and protonation reactions. The influence of competing ions, such as magnesium, calcium, sodium, and carbonate, is also considered, as they directly affect system buffering and mineral phase stability. Another major contribution is the introduction of the synergistic coefficient, a novel parameter that quantifies the enhancement of buffering and dissolution beyond additive behavior. This allows comparative assessment of synergistic potential across different wastewater compositions. It is demonstrated that two conditions are required for the manifestation of synergistic effects in wastewater systems: (a) the formation of a ternary complex, and (b) amplification of one or more physicochemical properties. Struvite satisfies both criteria, as it forms a stable solid ternary complex and exhibits enhanced solubility and buffering action under appropriate conditions. Thermodynamic analysis reveals that these synergistic effects arise from the formation of mixed-ligand complexes that stabilize pH and promote mineral recovery. Validation using real wastewater confirms the model predictive accuracy in identifying optimal pH and ion ratios. The thermodynamic relations derived from this study enable the design of new synergistic processes with targeted buffering and mineral recovery properties, supporting the advancement of sustainable and efficient wastewater treatment technologies.

Magnesium phosphate cements (MPCs) are advanced inorganic binders gaining prominence in specialized engineering due to their rapid setting and high early strength. These properties make them exceptionally suitable for a wide range of applications beyond ordinary Portland cement (OPC), including the rapid repair of critical infrastructure, waste encapsulation, soil stabilization, and the development of refractory and corrosion-resistant coatings. While the properties of MPCs based on ammonium and potassium phosphates are well-documented, a systematic study including sodium dihydrogen phosphate is notably absent from the literature. This study presents a comprehensive comparative investigation of MPCs formulated with three different phosphate salts: potassium dihydrogen phosphate, sodium dihydrogen phosphate, or ammonium dihydrogen phosphate. The research methodology was designed to evaluate and contrast key characteristics of these cements, including their reaction kinetics, workability in the fresh state, physical characteristics, and mechanical strength in the hardened state. To elucidate the underlying mechanisms governing performance, a detailed microstructural analysis was conducted using Scanning Electron Microscopy (SEM), while the reaction products were characterized through X-ray Diffraction (XRD) and attenuated total reflectance–Fourier transform infrared (ATR-FTIR). The findings from this comparative analysis are crucial for identifying the most suitable phosphate salt for specific applications, thereby enabling the informed development and optimization of MPCs for advanced and sustainable construction. Funding: This work was supported by the Russian Science Foundation (Grant No. 24-79-10320, https://rscf.ru/en/project/24-79-10320/).

The granitic and metamorphic rocks at the Gabal Mukattab area represent the north termination of the Arabian–Nubian Shield in Sinai, which, in turn, represents the northern part of the East African Orogeny. The geochronological dynamics of the magmatism that constructed the Arabian–Nubian Shield are critical in understanding these orogenies. Our study involved dating three metamorphic rocks (846 ± 4 Ma to 818 ± 5 Ma), five calc-alkaline granitic rocks (728 ± 6 Ma to 609 ± 5 Ma), and eleven alkaline granitic rocks (678 ± 7 Ma to 555 ± 3 Ma). In the studied region, the island-arc phase of magmatism activated between 846 ± 4 Ma and 818 ± 5 Ma. The consequent syn-collisional magmatism initiated from 728 ± 6 Ma to 668 ± 5 Ma, demonstrating the temporal domination of the subduction-related compressional regime. The post-collisional magmatism started at 610 ± 5 Ma, marking the shifting of the tectonic setting from a compressional to an extensional regime. The phase of magmatism dominated until 555 ± 3 Ma in the studied region, suggesting extending the ANS magmatic activity until the Phanerozoic edge. These findings challenge the classical distinction between older magmatism, characterized by calc-alkaline granitoids, and younger magmatism, characterized by alkaline granitoids. The pre-Neoproterozoic (pre-ANS) 16 zircon xenocrystals with ages ranging between 2084 ± 9 Ma and 1094 ± 8 Ma were yielded, which might support a reworked ancient magmatic source. Seven Phanerozoic zircons showed ages between 495 ± 3 Ma and 374 ± 4 Ma, hinting at potential Ordovician–Devonian magmatic events in the region.

This study investigates the mineralogical and geochemical characteristics of heavy placer deposits from the Chaliyar River in Kerala, India, with a focus on ilmenite. Sand samples were collected from five locations in the Nilambur region and examined through sieve analysis, heavy mineral separation, X-ray fluorescence (XRF), X-ray diffraction (XRD), and petrographic microscopy.

Grain size analysis revealed that most of the sediments are below 600 µm, with a dominant fraction around 180 µm, reflecting moderately high-energy depositional conditions suitable for heavy mineral accumulation. Heavy mineral separation allowed for the concentration of the dense fractions for further study. XRF analyses indicated notable enrichment of Fe₂O₃, TiO₂, ZrO₂, and Cr₂O₃, which confirmed the presence of ilmenite, zircon, and garnet. XRD confirmed the crystalline nature of these mineral phases, while petrographic line counting provided quantitative data on their relative abundances across grain-size classes and sampling sites.

The results highlight the occurrence of economically valuable heavy minerals, particularly titanium-bearing ilmenite, within the Chaliyar River sediments. The observed mineralogical and geochemical variations also reflect differences in source rock composition and sediment transport processes within the basin.

This work establishes a baseline for understanding the distribution and concentration of heavy minerals in the Chaliyar River and provides a foundation for future studies and resource assessment in Kerala’s placer-rich terrains.