Airborne dust poses significant challenges in limestone mining operations, affecting environmental quality, health, and operational efficiency. This study focuses on assessing the moisture retention capacity of saline water, specifically seawater, as a watering material for limestone haulage roads by conducting tests to evaluate its moisture retention capacity. Moisture retention capacity is determined by using two (2) tests: wind tunnel test and heat test (oven test). Wind tunnel test assesses the effectiveness of seawater in retaining moisture under specific wind speed, time, and mix ratios. While the oven test analyzes weight reduction in limestone–water samples subjected to temperature, time, and mix ratios. These experiments provide quantitative data on moisture retention capabilities of different watering materials: seawater, groundwater, and deionized water. The results of the two tests show that limestone samples treated with seawater exhibit higher moisture retention compared to those treated with groundwater and deionized water, indicating the superior effectiveness of saline water as a spraying material. By adopting seawater as a watering material, mining companies can reduce their fresh water usage and enhance their dust control efforts, resulting in improved environmental conditions and worker health. In summary, this thesis presents laboratory experiments, including wind tunnel tests and oven tests, to assess the moisture retention capacity of seawater as a watering material for dust suppression on limestone haulage roads. The findings contribute to the understanding of effective dust control strategies in the mining industry and provide practical recommendations for implementing saline water-based dust suppression methods in limestone mining operations.

Mine dust is a significant issue in surface mining operations, particularly on haul roads. This study investigates the potential of xanthan gum as an eco-friendly dust suppressant in nickel mines. The objectives are to assess its effectiveness in terms of infiltration depth capacity and wind erosion resistance, and determine the terms of concentration for desired performance on a lab scale level. Samples of nickel laterite soil were collected from CTP Construction and Mining Corporation, Adlay, Carrascal, Surigao del Sur, Philippines. Xanthan gum solutions at concentrations of 1g/L, 2gL, and 4g/L, along with water (mine water and deionized water) were tested. Infiltration depth and wind tunnel experiments were conducted to evaluate the performance of xanthan gum. Results were analyzed through P-test, ANOVA, and Multiple Comparison test. The results showed that xanthan gum solutions achieved infiltration depths within the recommended range of 10-20 mm, outperforming both mine and deionized water. The concentration of 4g/L exhibited the lowest weight loss in the wind tunnel test, indicating superior wind erosion resistance compared to lower concentration and water. The concentration of 1g/L was found to be sufficient for desired outcomes. The use of xanthan gum presents an environmentally friendly alternative to traditional methods, reducing dust emissions and minimizing the use of hazardous chemicals in the mining industry. These findings provide valuable insights for dust control measures and lay the foundation for future research on xanthan gum as a dust suppressant.

The reactivity of basaltic minerals toward CO₂ mineralization remains debated: laboratory studies at low temperatures identify plagioclase as the most reactive, while reservoir-scale experiments emphasize olivine. This study reconciles the apparent contradiction by establishing that mineral reactivity is not an intrinsic property but a condition-dependent outcome governed by temperature, pressure, pCO₂, and fluid chemistry. Through a synthesis of experimental and modelling evidence, we construct a unified framework incorporating five key controls: dissolution kinetics, surface accessibility, geochemical environment, cation stoichiometry, and reaction timescale. Under near-surface laboratory conditions (25–50 °C, acidic pH), plagioclase dissolves rapidly via proton-promoted hydrolysis, releasing Ca for early carbonate formation. At reservoir conditions (100–200 °C, high pCO₂, saline or wet supercritical CO₂), olivine dominates, showing 1–2 orders of magnitude higher dissolution rates and facilitating fast Mg-carbonate precipitation before silica passivation slows reactivity. Intermediate conditions (50–100 °C) yield mixed Ca- and Mg-carbonates, highlighting the futility of single-mineral extrapolations. Pyroxenes remain kinetically sluggish in all regimes. This perspective demonstrates that successful in situ mineralization depends on engineering reservoir conditions, optimizing temperature, salinity, and fluid pathways rather than simply selecting mineral-rich targets. By reframing mineral reactivity as a dynamic, environment-driven function, this study provides a mechanistic foundation for improved experimental design, predictive modelling, and site selection in CO₂ storage operations within basaltic formations.

The removal of thallium (Tl⁺), a highly toxic heavy metal, from aqueous environments is a critical environmental challenge. Zeolites, crystalline microporous aluminosilicates with tunable composition and high cation-exchange capacity, are widely used in environmental remediation due to their ability to selectively capture metal ions from contaminated waters.

We investigated the selective uptake of Tl⁺ by potassium-form L zeolite (K-L) and evaluated the structural adaptations accompanying cation exchange using X-ray powder diffraction (XRPD), Rietveld refinements, thermal analysis, and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Two additional zeolitic materials—protonated ferrierite (obtained by calcination of its ammonium form) and 13X zeolite, commonly used in environmental applications—were also tested. Batch adsorption experiments were conducted at neutral pH (~7), including isotherms and kinetic studies for 13X. All three materials were further assessed in real Tl-contaminated waters (~17 ppb).

All zeolites achieved nearly 100% Tl⁺ removal in synthetic solutions at 500 ppm and retained significant uptake at high concentrations (~0.5 M). Structural refinements revealed concentration-dependent framework responses: K-L showed minimal lattice expansion at low Tl⁺ loading and anisotropic expansion at high loading, associated with K⁺/Tl⁺ exchange, reduced hydration, and extraframework reorganization. Similar trends were observed for ferrierite and 13X. In real waters, despite competing ions, all three zeolites reduced Tl⁺ concentrations to ~2 ppb.

Tl⁺ incorporation induces precise structural adaptations in zeolitic frameworks, including selective cation redistribution, anisotropic channel expansion, and reorganization of the water network. K-L, 13X, and protonated ferrierite demonstrate high efficiency for Tl⁺ removal from both synthetic and natural waters, highlighting their strong potential for environmental remediation of thallium-contaminated systems.

This study investigates the redox geochemistry and soil characteristics of the Caimpugan Peatland within the Agusan Marsh Wildlife Sanctuary, Mindanao, Philippines. The ability of these peatlands to accumulate and preserve carbon is shaped by these processes that regulate microbial and geochemical activity. Despite the ecological importance of these systems, the redox geochemistry of peatlands in the Philippines remains poorly studied, especially in understanding how local peat environments function as carbon sinks. Peat cores were collected from various forest types and depths, reaching up to 5 meters below the surface, to evaluate gravimetric moisture status, redox, and geochemical conditions. The study revealed that the maturity of the peat grades, ranging from fibric peat in the upper layers to clayey peat in the lowest sections, reflecting past changes in water conditions and organic matter input that affect microbial activity and redox processes. The peat exhibited a very high moisture content, reaching up to 384.34%, indicating persistent saturation and limited oxygen diffusion, favoring the buildup and preservation of organic material. Redox analyses revealed that 7.4% of the samples fell within the iron reduction zone, primarily near the surface, while 92.6% fell within the sulfate reduction zone. The strong dominance of sulfate-reducing conditions suggests a highly reduced environment where most available electron acceptors are depleted. Redox potential values were observed to nearly reach the threshold of methanogenesis, reflecting extremely low oxidation states typical of stable carbon-preserving systems. Geochemical results identified major oxides, including SiO₂, Al₂O₃, SO₃, Fe₂O₃, TiO₂, P₂O₅, CaO, and MgO, which influence nutrient exchange, buffering capacity, and redox balance. Overall, the Caimpugan Peatland shows consistently reduced, saturated, and chemically stable conditions that support long-term carbon storage. These findings provide a clearer understanding of peatland redox environments in the Philippines and their role in sustaining carbon reservoirs under natural tropical conditions.

As human-induced carbon emissions continue to increase, the demand for effective strategies to achieve net-zero emissions also grows. One promising approach is carbon sequestration via enhanced rock weathering, specifically through carbon mineralization. This process entails the weathering of ultramafic to mafic minerals, leading to the formation of stable carbonate minerals that help regulate atmospheric CO₂ levels. This study employs petrographic analysis to evaluate the potential of mafic rocks in the Mindanao Eastern Pacific Cordillera, southern Philippines, for atmospheric CO₂ sequestration. Using point-counting techniques on prepared thin sections, the study quantifies the abundance of reactive minerals. The modal percentages of olivine, pyroxene, and plagioclase—key reactive minerals—are determined, and their corresponding CO₂ uptake capacities are used to calculate the total potential CO₂ sequestration. Results from petrographic analysis indicate that mafic rocks from the Dinagat Islands, characterized by high plagioclase, pyroxene, and olivine contents with minimal alteration, exhibit the greatest estimated CO₂ uptake at 16.11 wt% CO₂. Basalts from the Siargao Islands show a potential CO₂ uptake of 14.85 wt% CO₂, attributed to their abundance of plagioclase and pyroxene. Meanwhile, the Bacuag Formation’s porphyritic basalts in Surigao del Norte, containing significant plagioclase, moderate pyroxene, and lesser olivine, can sequester up to 12.69 wt% CO₂. In contrast, although reactive minerals are present in the Barcelona Formation mafic rocks in Surigao del Sur, their potential CO₂ uptake is reduced to 8.92 wt% CO₂ due to the transformation of these minerals into clay minerals, zeolites, and chlorites during weathering. Variations in CO₂ uptake among the studied formations highlights the importance of mineralogical composition and degree of alteration in assessing a rock’s suitability for carbon mineralization. Overall, these results underscore the viability of utilizing select mafic rock formations in the southern Philippines as natural carbon sinks to support regional and global net-zero initiatives.

The circular recovery and reuse of nutrients from wastewater represent key strategies for achieving sustainability targets and the objectives of the EU Green Deal. In this study, the selective capture of ammonium (NH₄⁺) was investigated using two distinct zeolitic tuffs: one rich in chabazite and another enriched in both phillipsite and chabazite. This research aimed to assess their suitability for farm-scale applications by testing different anaerobic digestates, originating from swine, cattle, and municipal solid waste.

Adsorption isotherms and kinetic experiments were conducted to evaluate the influence of initial NH₄⁺ concentration, contact time, ionic competition (notably K⁺), total solids content, and pre-treatment conditions. Equilibrium data were best described by the Freundlich model, indicating a heterogeneous and multilayer adsorption process, while kinetic results fitted well with the pseudo-first-order and intraparticle diffusion models, highlighting ion exchange and diffusion as the predominant mechanisms. Under the same operating conditions, the chabazite-rich tuff exhibited higher ammonium uptake and faster adsorption kinetics compared to the phillipsite–chabazite tuff, reflecting differences in mineralogical composition and cation exchange capacity. NH₄⁺ removal efficiency decreased with increasing K⁺ concentration and solids content, whereas livestock digestates achieved the highest nitrogen recovery per gram of tuff due to their favorable composition and kinetics. Among the pre-treatments, centrifugation proved most effective, enhancing the accessibility of active exchange sites. A preliminary farm-scale batch test using microfiltered swine digestate at a 3% solid-to-liquid ratio confirmed operational feasibility, resulting in an estimated nitrogen recovery of 715 kg N per year. Overall, these results highlight the potential of zeolitic tuffs for promoting nutrient circularity in agriculture and provide insights for selecting materials to maximize ammonium recovery under diverse farm-scale scenarios.

Sesquioxide minerals (R₂O₃) occur widely in natural systems, including Fe- and Al-based soil minerals such as hematite and corundum, and exist as technologically important engineered oxides such as Ga₂O₃, In₂O₃, and various rare-earth sesquioxides. Although these compounds are primarily recognized as highly thermodynamically stable and relevant in the environmental context, their nanoscale stability mechanisms in the presence of ambient geochemical conditions remain poorly understood. This study computationally evaluates the thermodynamic stability of representative natural and synthetic sesquioxide nanominerals to address this gap. Density functional theory (DFT) calculations were performed to obtain internal energy, enthalpy, Gibbs free energy, heat capacity (Cv), entropy, dipole moment, and point-group symmetry for selected R₂O₃ systems. For arsenolite-type As₂O₃, the verified values include an internal energy of −127691.670510234 eV, free energy of −127692.832381907 eV, Cv of 18.804 cal·mol⁻¹·K⁻¹, entropy of 91.852 cal·mol⁻¹·K⁻¹, a dipole moment of 5.2738 Debye, and Cs symmetry. Additional sesquioxides, including Fe₂O₃, Ga₂O₃, Sc₂O₃, Cr₂O₃, and others, were analyzed using the same computational protocol, with comparative trends observed across the dataset. The results indicate symmetry-dependent variations in electronic structure and dipole behavior even when their overall thermodynamic magnitudes remain comparable under standard conditions. These findings support the potential of quantum-chemical approaches for predicting nanoscale mineral stability in geochemical environments. Further work is needed to investigate interactions with aqueous ions and to explore stability variations across broader geochemical variables such as pH and redox conditions, to better link computational signatures with natural environmental behavior.

Imenite is a diamond-associated mineral. In kimberlites, ilmenite occurs as megacrysts and macrocrysts (monomineral nodules), as well as phenocrysts within a fine-grained groundmass. The chemical compositon of ilmenite from kimberlites is characterized by high contents of Cr, Nb, and Zr. Large grains sometimes demonstrate wavy extinction and a «mosaic» structure, indicating the influence of deformation processes after crystallization. Ilmenite is also found in lithospheric mantle rock ranges from 1.5% (Udachnaya pipe, center of Siberian craton, Yakutian kimberlite province) to 4-7% (Obnazhennaya pipe, northeastern margin of the craton). Ilmenite has a variety of morphologies. In the Mir and Obnazhennaya pipes, this mineral occurs as small, rounded, and elongated inclusions (up to 20-50 μm in size) in garnet and clinopyroxene, as well as needles and lamellae (up to 20-40 μm thick), following the crystallographic orientation of the host mineral. These are presumably exsolution structures. Lamellas show a wide range of chemical compositions, from 39.7 to 57.6 wt.% TiO2 and 4.2-12.5 wt.% MgO. Large variations in the compositions of ilmenite lamellas from pyroxene and garnet crystals suggest that these ilmenites formed as exsolution structures during the gradual cooling of initial pigeonite megacrystals. Ilmenite from mantle rocks forms relatively large (0.3–2 mm) isometric grains with thin elongations parallel to the banding and lenticular porphyroclasts with features of mosaic polygonality, indicating the initial stage of rock deformation. Thus, ilmenite from kimberlite xenoliths in the central Siberian Craton occurs in polymictic breccias and exsolution structures in other minerals and is predominantly of cumulative origin. Ilmenite from mantle xenoliths from northeast of Yakutia has a variety of morphologies, which allows us to distinguish several generations and indicates a multi-stage genesis and heterogeneous lithospheric mantle beneath the shallow northeastern margin of Siberain craton.

Passive thermal energy storage materials are increasingly recognized as cost-effective solutions for reducing cooling energy demand in regions with extreme heat. Organic phase change materials (PCMs), particularly paraffin wax, offer strong thermal buffering performance due to their high latent heat capacity. However, their inherently low thermal conductivity and limited structural stability reduce practical efficiency in passive cooling systems. This study aims to develop and evaluate mineral-enhanced organic PCM composites by incorporating UAE-derived minerals—specifically limestone, dolomite, silica sand, and gabbro fines—to improve heat transfer and mechanical integrity. Organic PCM composites will be prepared using paraffin wax blended with varying mineral loadings (5–25 wt%). Samples will be fabricated using simple casting techniques, and their thermal performance will be characterized through controlled hot-plate heating (≤90 °C), embedded thermocouple measurements, and cooling cycle experiments. Key evaluation parameters include melting and solidification behavior, heat absorption and release characteristics, thermal conductivity enhancement, and dimensional stability during repeated thermal cycling. It is anticipated that UAE minerals—particularly silica sand and dolomite—will significantly improve the thermal conductivity and stability of the PCM matrix. The expected outcomes will help identify safe, low-cost, and locally sourced mineral–PCM combinations suitable for passive cooling applications in building envelopes, rooftop thermal buffers, and compact thermal energy storage units. This proposed study demonstrates the potential of leveraging abundant UAE mineral resources to create sustainable, climate-adapted thermal energy storage materials for extreme desert environments.