The present work focuses on the Tiouit mining zone that is part of the Moroccan Eastern Anti-Atlas. The study area is characterized by its strategic mining aspect considering the mining showings related to its geological, structural, and geodynamic factors. The mining site of Tiouit is very well known by the gold mine currently in shutdown. The genetic models proposed by different authors agree on an epithermal origin of copper porphyry type. This type of deposit is characterized by a strong radioactive activity related to the circulation of hydrothermal fluids materialized by enrichment in potassium and depletion in Thorium, a low magnetic susceptibility due to oxides a low apparent resistivity to the presence of conductive minerals.

The main objective of the present work is to use principal component analysis (PCA) on the various airborne geophysical data, including gamma-ray spectrometry (concentrations of radioactive elements ⁴⁰K and ²³²Th), magnetism (magnetization contrast due to magnetic susceptibility), and electromagnetism (apparent electrical resistivity) to describe the physicochemical behavior of the mining zones in operation as well as to prospect other zones favorable for exploration.

The geostatistical study of these data highlights the adequate principal component (PC) to visualize these geophysical variables. We chose PC4 to visualize the zones favorable for mining concentration because it describes the same physical and chemical characteristics represented by the Tiouit alteration zone. The collection and X-ray fluorescence analysis of 32 samples in the field yielded high grades of Arsenic (84 g/t), Copper (5.87%), Iron (19%), Lead (5.7%), and Zinc (7%).

10th Khutor deposit is located in the Republic of Khakassia and confined to the coal-bearing formation of Carboniferous age within the development of continental tuff-sandy-argillaceous sediments. In terms of mineral composition, bentonites are mainly composed of Al-rich montmorillonite. The content of montmorillonite reaches a maximum of 70-75%, with an average content of 55 to 70%. It is one of the main sources of bentonite for the metallurgical and foundry industries in Russia.

One of the distinctive features of bentonites from the 10th Khutor deposit is that despite the age of the deposit, about 350 million years, and the presence of an initial phase of metamorphism, as evidenced by the formation of hard coal, these bentonites retained the ability to swell and have high thermal stability. The formation of bentonites is associated with the decomposition of volcanic ash of rhyodacite and dacite composition in zones of shallow seawater - bays and lagoons. The properties of bentonite were influenced by the initial stage of metamorphism.

The main purpose of this work was to establish the conditions for the formation of this deposit, as well as to study the features of the mineral composition and physicochemical properties of these raw materials. In addition to fundamental issues, the aim of the work was applied research on the properties and quality of bentonites.

Beneficiation of iron and steel slags have a great potential in mitigating high levels of anthropogenic carbon dioxide (CO2) gas emissions. Carbonation of calcium and magnesium leaching solutions produce precipitates that promise to act as fluxing agents in various industries. There is also a need to study physico-chemical factors affecting the extraction of these elements and their kinetic behaviour. A calcium-rich blast furnace ironmaking slag milled to 80% -75µm was used in an experiment to study the effect of reaction temperature on the dissolution of calcium. An orbital shaking incubator was used by applying the one-factor-at-a-time method for a 2-hour leaching test. Reaction temperature was controlled at 30⁰C, 50⁰C, 70⁰C and 100⁰C at constant agitation speed of 200 rpm, 0.5M of lixiviant concentration and solid-to-liquid ratio kept at 200 g/L. CH3COOH, (NH4)2SO4 and NH4Cl were tested individually as lixiviants. Atomic Absorption Spectroscopy (AAS) was used to analyse the concentration of calcium leached. Consequently, the findings showed that temperature is the critical operating parameter that yielded exceptionally high calcium extraction. CH3COOH yielded 80%-90% of calcium extracted under high reaction temperatures. The kinetic data for the effect of reaction temperature leaching data fitted one shrinking core model equation, which described diffusion-controlled leaching reactions. The diffusion controlled by a product layer model was fitted and the activation energy were calculated as 19.4930 kJ/mol for NH4Cl solvent. (NH4)2SO4 and CH3COOH did not fit into any model because of undefined kinetic data and formation of gelatinous silica layer observed during the leaching process.

The North-Eastern of Morocco was widely known for its mining potential, so discovering new structural guidelines was indispensable to find out new mineralization. Indeed, applying airborne magnetic techniques proves its efficiency in underlining new tectonic accidents and highlighting magnetic sources mostly hidden by Quaternary sedimentary covers. A magnetic anomaly map was established to attain this goal, basing on powerful operators (reduction to the pole, upward continuation, and Euler deconvolution), made on airborne data surveys of the study area. The elaborated map shows: (1) zones of strong magnetizations related to the Tertiary and Quaternary volcanic lavas partly outcropping in the Oujda and Saka regions to the iron and manganese mineralization concentrated in the Triassic beds. (2) Zones of relatively low magnetic response came from basaltic cones filled in a small graben at Oujda region. (3) Zones of low magnetization corresponded to the Quaternary and Tertiary cover or the Triassic-Jurassic deposits. We have established a magnetic lineaments map that emphasized deep faults, two main trends have been identified: NE-SW with ENE-WSW and E-W, they are considered as a major’s accidents because their depth reach to 2 km, as much as they inherited from the Hercynian and Alpine tectonics.

Man-made deposits of coal ash – a solid by-product of coal combustion - accompany practically every thermal power station and many industrial plants. The total annual production of coal ash worldwide (mainly fly ash) is700–800 million tons with less than 30 % being reused. The disposed coal ash has become a matter of serious environmental concern because of its heavy metal contents which may leach out causing serious pollution of natural water bodies and soil. The mineral composition of coal ash is represented mainly by the glass phase, similar to volcanic glass, as well as by quartz, mullite, magnetite, etc. In recent years, intensive research has been carried out in the use of fly ash for the synthesis of geopolymer materials. Geopolymers are a subclass of alkali activated materials prepared by the reaction of low-calcium, natural and industrially produced aluminosilicates, with an alkaline agent (e.g. alkali metal hydroxide solution or liquid glass) at near ambient temperatures. Due to their energy savings, environmentally friendly processing and high performance, geopolymers are gaining attention in the construction industry as a promising replacement for traditional Portland cement. In this work, we focused on the effect of natural dolomite addition to fly ash and mechanical activation of this two-component mixture on the geopolymerization process. The influence of dolomite dosage and mechanical activation time in a planetary mill on the reactivity of the raw material in relation to sodium hydroxide solution and on the geopolymer strength was investigated.

The studied manganese prospects within ophiolitic complexes are located in southeast of Birjand, South-Khorasan, east of Iran. The ophiolitic sequence in this region hosts manganese ores occurring as small discrete patches associated with radiolarian cherts and shales. The major manganese ore minerals are pyrolusite, braunite, bixbyite, ramsdellite, and romanechite showing replacement, colloidal, and brecciated textures. The major non-opaque gangue minerals are, calcite, silica and gypsum. The high mean values of Mn/Fe (15.32) and Si/Al (15.65), and low mean concentration values of rare elements like Cu (86 ppm), Ni (250 ppm), and Zn (149 ppm), and high Ba (average 1883.77 ppm), with low Pb (average 52ppm) and low Ce (average 15.7 ppm), also The Co/Zn (average 1.055), Ce/La ratio (average 2.96) suggest a distal hydrothermal source. Investigations on fluid inclusions hosted by calcite demonstrate that the ore-forming solutions had salinities within the range of 0.5-4.5 wt% NaCl eq., homogenization temperature range of 100-220˚C and density about 0.8-1 g/cm³. The pressure was estimated to be about 50 bars, corresponding to a depth of ~150 meters at the time of formation. Fluid inclusion data are interpreted as evidence for formation from seafloor Mn-rich hydrothermal exhalative fluids. Hydrogenous processes played no significant role in ore genesis. The geological and geochemical results also revealed that deposition of the ores occurred in the upper parts of the ophiolitic sequence by submarine exhalative processes. Intense hydrothermal activities caused leaching of elements such as Mn, Fe, Si, Ba, As, and Sr from basaltic lavas (spilites) through concurrent faults with deposition. These elements were fed to a sedimentary basin and during retreat of the sea accompanied by onset of oxidising conditions. The primary manganese minerals were Mn oxides and hydroxides which have gradually been converted to psilomelane and finally pyrolusite, braunite and bixbyite. During deposition of Fe and Mn from hydrothermal solution, they became decoupled from one other, producing different Mn/Fe ratios in sedimentary exhalative deposits (sedex-type). The Mn/Fe ratios are 3.99 to 40.81 (ave., 15.32). Very high and very low ratios of Mn/Fe can be interpreted as fractionation and separation of these two elements from transportation during hydrothermal activity and mineralization. So, high Mn/Fe ratios here can be considered as in submarine hydrothermal deposits. On a Pb versus Zn diagram, the manganese prospects display greater similarities with sedex deposits.

The coupled substitution between Na+Si and Ca+Al in the plagioclase solid solution results in a continuous variation in the Al/Si ratio of the composition, which is the reason for the complicated ordering patterns in the intermediate plagioclase feldspars like labradorite. Both fast-cooled and slow-cooled labradorite feldspars display the incommensurately modulated structures. The ordering pattern in the incommensurately modulated structures of e-plagioclase (characterized by the satellite diffraction peak called e-reflections) is the most complicated and intriguing. The modulated structure has a superspace group symmetry of X(αβγ)0 with a special centering condition of (½ ½ ½ 0), (0 0 ½ ½), (½ ½ 0 ½), and the q-vector has components (i.e., δh, δk, δl) along all three axes in reciprocal space. Displacive modulation, occupational modulation, and density modulation are observed in slowly cooled labradorite feldspars. No density modulation was observed in fast cooled (volcanic) labradorite feldspars. The amplitudes of the modulation waves are new parameters for quantifying the ordering state of labradorite. Iridescent labradorite feldspars display exsolution lamellae with average periodicity ranging from ~ 150 nm to ~350 nm. Compositional difference between the lamellae is about 12 mole % in anorthite component. Areas or zones with red iridescent color (i.e., long lamellae periodicity) always contain more Ca (~ 1 to 3 mole %) than the areas with blue (or green) iridescent color within the same labradorite crystal. We proposed that the solvus for Bøggild intergrowth has a loop-like shape ranging from ~An₄₄ to ~ An₆₃. The Ca-rich side has higher temperature than the Na-rich side. The shapes of satellite peaks, the distances between e-reflections (modulation periods), and even the intensity of c-reflections may also be used to evaluate the ordering state or cooling rate of the plagioclase feldspar. Both modulated structure and the exsolution lamellae can be used as proxies for quantifying cooling rate of a labradorite and its host rock.

Clay minerals are natural, abundant and widely used industrial raw materials. Kaolinite is a 1:1 type, layered phylloaluminosilicate, constituted by Si⁴⁺-centered tetrahedral (T) and Al³⁺-centered octahedral (O) layers.

Kaolinite has a strong potential as innovative, environmental-friendly photocatalyst, due to its not yet understood photocatalytic activity. Photocatalytic investigations require clean samples, free of mineral contaminants. Natural kaolinite is obtained through mining of kaolin. The mineral composition and varying properties of kaolin significantly influence their catalytic activity, and therefore pose an adverse impact on their catalytic investigations. Laboratory synthesis of kaolinite offers a way to obtain kaolinite with the desired properties and purity.

In the present work, the laboratory synthesis and evaluation of a synthetic kaolinite and its TiO₂ nanocomposites are reported. The hydrothermal synthesis method was chosen to minimize pollutants. The effect of the applied acid concentration and liquid phase ratio were investigated. The synthesized kaolinites were characterized by XRD, FTIR-ATR, TG/DTG/DTA. The mineral composition, the presence and crystallinity (Hinckley, Stoch, Range-Weiss indices) of kaolinite were determined by XRD. Fourier transform infrared spectroscopy was utilized to identify kaolinite vibrations. Thermal stability, mineral purity and dehydroxilation was determined by TG/DTG/DTA. The morphology and elemental composition maps of the best sample was investigated by TEM-EDX.

Sol-gel method and thermal treatment were used to prepare synthetic kaolinite-TiO₂ nanocomposites with varying surface concentrations of TiO₂. The composites were characterized by XRD and FTIR-ATR.

The photocatalytic activity of the samples were investigated by the aqueous degradation of an oxalic acid test compound upon 365nm UV irradiation.

Acknowledgement: The work was supported by the GINOP-2.3.2-15-2016-00016 and GINOP-2.3.2-15-2016-00053 projects (cofinanced by the Széchenyi 2020 program). B. Zsirka acknowledges the support of the Ministry of Human Capacities (NTP-NFTÖ-19-B-0154).

The kinetic population balance model (PBM) is used to predict the particle size distributions of batch ball milling products. However, the rate parameters, as well as the solution of this model, may not be found in the non-first-order breakage region. This study alternatively represents a PBM-coupled simulation algorithm, which resembles a time-implicit or explicit matrix PBM for ball milling. The algorithm simply predicts the progeny size distributions after successive ball-particle impact events occurring in a batch ball mill. Therefore, the algorithm can accurately estimate the progeny size distributions either under the first-order or the non-first-order breakage region. For the purpose of this study, a few case studies were presented to demonstrate the accuracy of the algorithm.

Annatto dye is a natural organic dye belonging to carotenoids, whose main components are bixin and norbixin. Due to its low stability, it is convenient to protect the dye molecules with other materials. The use of clay minerals is an alternative, which are phyllosilicates with attractive physico-chemical properties, such as high specific surface area, cation exchange capacity, mechanical/chemical stability and non-toxicity. The main purpose of this work was to develop hybrid materials, using annatto dye and clay mineral modified with different inorganic cations, and then, to evaluate the stability of the new pigments. The process of preparing the modified clay minerals involved mixing a synthetic montmorillonite in solutions containing the precursor salts of the metal cations. Subsequently, the dye was dissolved in a solution containing water and alcohol, followed by filtration and mixed with the modified clay, giving rise to the hybrid pigments. Through the characterizations, it was noted that a variety of colors was obtained, and the sample containing aluminum was the one that most adsorbed the dye and showed a significant increase in stability at high temperatures. This hybrid material was better than to the dye in its pure form. Therefore, the bixin/montmorillonite pigments are promising for replacing artificial colors in practical applications such as in the cosmetics, food or pharmaceutical industries.