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The procedure is proposed for structuring complex coal deposits with respect to quality indexes obtained using ArcGIS with a view to substantiate rational trends in mineral use. The article reports the research on assorting Elginsk black coal reserves in South Yakutia based on volatile content, plastic layer thickness, coal grades, process groups and subgroups.

The article presents new test results on structural and chemical properties of mineral formations on the surface of natural hydrophilic diamonds using Raman, X-ray phase and Auger spectroscopy methods. Analysis of morphological features of nano formations involved scanning electron microscope Jeol-5610 and analyzer INCA. Based on the studies into phase composition of diamonds non-recovered in the circuit of kimberlite ore processing, two types of mineral formations are discovered on their surface: micro-formations as silicate nature globules less than 1 µm in size and silicate nano films more than 5 nm thick. The tests detect also presence of layered talcose silicates that make diamond surface hydrophilic.

The authors have tested effect of type and energy of mechanical impact on selectivity of spodumene ore breakage in a disintegrator and in vibratory and ball mills in terms of pegmatite with lithium content of 0.1%. It is shown that the highest efficiency of mineral dissociation is achieved in disintegration by free impact. Analysis of grain-size distribution and chemical composition and the X-ray study also reveal advantage of the disintegration process, which allows higher content and recovery of lithium in concentrate at reduced sliming.

Under discussion is recoverability of noble and rare metals from caustobioliths (shale, natural bitumen, etc.). The presented mineralogical and technological analyses of samples show higher content of valuable microelements in some of them. All tested samples contain various rank carbon. Depending on the type of the raw material, the research follows one of three lines: stage-wise diagnostic sorption leaching, flotation with pre-milling in amino acetic acid and magnetic concentration. Based on the examination of scattered carbon substance in caustobioliths, it is supposed that concentrations of metals are asphaltene fractions of bitumoids (bitumen-like substance). The research results show prospect of using this nonconventional coal-bearing raw material as a source of noble and rare metals.

Various mechanochemical approaches to improving the sorption properties of metal materials accumulating hydrogen are discussed. Some experimental results illustrating the possibilities of each approach are presented. It is established that the sorption characteristics of known metal accumulators of hydrogen can be improved by affecting their structure, morphology and surface properties with the help of the mechanical activation and mechanical alloying with various kinds of additives. The possibility to search for new hydrogen-absorbing materials through the mechanochemical synthesis of metastable composites of components of various natures including thermodynamically immiscible components was demonstrated. These composites may possess a high reactivity with respect to hydrogen and serve as precursors for the synthesis of new phases. The synthesis of intermetallic compounds and hydride phases directly during the mechanochemical treatment also opens opportunities for the preparation of new materials promising for hydrogen storage.

Synthesis method is based on grinding coarse aluminium powder in the planetary centrifugal mill in the presence of a surface-active organic substance that promotes a decrease in the size of aluminium particles and covers the resulting products with a film that is impermeable for oxygen. The synthesis is carried out in the flow of high-purity nitrogen. At a temperature of 300–400 °C, the organic film is evaporated from the precursor particles, aluminium surface, active toward nitriding, shows up, and the reaction takes place at a temperature of about 750 °C. The yield of the product is about 100 %, its oxygen content is less than 0.6 mass % (the detection limit for the method used). Because of low temperatures, the resulting powder is weakly agglomerated; particle size varies within the range 350–500 nm.

The products of the joint mechanical activation of kaolinite with polymers (Sevilen, poly-N-vinylpyrrolidone and polyamide PA-6) in a high-energy ball mill were studied by means of IR spectroscopy and X-ray phase analysis. It was established that for definite polymer content of the initial mixture the mechanochemical interaction of kaolinite with polymer occurs, and the chemical bond is formed between them.

Mechanical milling is widely used for the purpose of efficient mixing of the components of particle-reinforced composite materials, which are further obtained in a bulk form by consolidation of the milled powder mixtures. Using the Ti₃SiC₂–Cu system as an example of a metal matrix composite with a ductile matrix and a reinforcement phase prone to chemical interaction with the matrix at elevated temperatures, we show that the effect of the preliminary mechanical milling of the components is seen not only in the uniformity of distribution of the reinforcing particles in the matrix but also in the consolidation behavior of the powders. The influence of the presence of composite agglomerates in the milled mixture on the processes induced by heating during consolidation is demonstrated by detonation spraying of the mechanically milled and mixed Ti₃SiC₂–Cu powders in comparative experiments and Spark Plasma Sintering of the Ti₃SiC₂–Cu agglomerates of different morphology. Interparticle interactions that are affected by the presence/absence of composite agglomerates and their morphology are the interfacial chemical reactions, the degree of transformation and melting of the copper matrix in the contact regions.

Glauconite and glauconite sand were used as starting materials. To prepare adsorbents on the ground of glauconite, mixtures of glauconite sand and sodium dihydrophosphate NaH2PO4 at various weight ratios (1 : 1, 2 : 1, 3 : 1, 4 : 1) were subjected to the mechanical activation (MA) in a planetary mill. MA products were studied by methods of X-ray phase and thermal analysis. Degrees of sorption for ions of manganese, cuprum, nickel and zinc were determined from appropriate solutions of sulphates within the concentration range of 60–1000 mg/L.

Thermal decomposition of the samples of cold-weather storage bitumen (heating with water vapour) was studied by means of thermogravimetric analysis. Bitumen was treated to remove water according to the regulations and with higher temperature and treatment time than those stated in the regulations. The effect of mechanically activated mineral additive and the additive imitating pyrobitumen on thermolysis was considered. Calculated activation energies of thermal decomposition of bitumen samples are reported.