The physicochemical research of ammonium fluoride processing of ash and slag waste is performed as a case-study of ash waste of Blagoveshchensk thermal station and fly ash of Amur experimental ...technology facility. The optimized conditions are determined for some reactions, including fluorination of feedstock in the temperature range of 50–200 °C, sublimation of ammonium hexafluorosilicate at 350–550 °C, as well as production of amorphous silica, fine-grain alumina, red iron-oxide pigment and calcium fluoride. The basic distribution patterns of rare earths, including Sc and Y, during ammonium fluoride processing are determined. The authors have developed the effective innovation technology for various ash and slag waste processing with extraction of ore microconstituents.
The kinetic characteristics are calculated for the chemical reactions in the process chain of ammonium-fluoride processing of aluminosilicate raw materials to extract useful components, specifically, ...the reaction of ash fluorination with ammonium bifluoride and the reaction of decomposition with sublimation of ammonium fluoride salts. The kinetic characteristics are calculated using parametric regression and correlation analysis. The kinetics of the fluorination reaction is calculated using a power law and the decomposition reaction with sublimation of ammonium fluoride salts according to the Erofeev–Avraami equation. The differential and integral kinetic curves of both reactions are studied, and the calculated response functions are constructed. The built linear regression model is tested using five statistical hypotheses, namely, the hypotheses of the homogeneity of the reproducibility variance, the adequacy of the regression model, the significance of the regression coefficients, the practical significance of the response function, and the significance of the correlation coefficient. The calculations are carried out using a Visual Basic program written by the authors. The products of combustion of coal from the ash-disposal site of the Blagoveshchensk CHP plant are studied.
The physicochemical analysis of distribution of useful components in processing of ash and slag of the thermal energy sector plants is performed. The article describes thermodynamics and kinetics of ...chemical reactions during agglomeration of feedstock and ammonium hydrofluoride at the temperatures of 50–200 °C, sublimation of ammonium hexafluorosilicate in the temperature range of 350–550 °C, production of amorphous silica nanoparticles, alumina particles and red iron oxide pigment, as well as formation of calcium fluoride (Ca, Y)F
2
which is a concentrator of rare and other elements. The efficient technology is developed for processing of electromagnetic fraction of ash and slag with integrated recovery of various useful components.
It has been shown that an electric spark discharge in saturated alkaline solution acts as a catalyst of ionization during the decomposition of kaolinite into aluminate and silicate components. The ...production of aluminum hydroxide from KM-1-grad kaolin (Chalgansk deposit) is 24.8–37.2% of the estimated value.
The undertaken research is aimed to reveal optimal physicochemical conditions for deep conversion of calcium-bearing alumosilicate raw material. An innovative technology of integrated extraction of ...nano-dispersion amorphous silica, alumina, calcium fluoride and other useful elements has been developed.
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The sedimentary stratum of the oceanic crust with a thickness of up to 3 kilometers and younger than the Jurassic age deposits of organic matter (OM) sediments, is saturated with O
2
absorbed and ...dissolved in the ocean with binding energy in the range of 5–15 kJ/mol. During subduction of the oceanic crust into the mantle with
T
= 170–500°C, fluids of O
2
, H
2
O, CO
2
are released and are subsequently filtered to the surface of the suprasubduction roof. The fluid O
2
oxidizes the matters of the sedimentary cover, the mantle and the roof with O
2
energy release of 14.97 kJ/kg. This results in the formation of a magma chamber. The melts of the chamber are divided with respect to density and composition into light-acidic enriched in SiO
2
and compact—basic enriched in Са, Мg, K. The discharged acidic melts form a crust of a continental type. Energy saturation of the magma chamber is increased by exogenic energy of OM pyrolysis. At depths of subduction at
T
= 500–1200°C, OM undergoes deep metamorphism with the release of oil and gas fluids which form a planetary system of hydrocarbons. The continental crust and the hydrocarbon system are formed in many respects due to the biosphere conversion of solar energy, oxygen, and OM to the composition of the Earth’s outer shells.
The processes of physicochemical treatment of nepheline concentrates are studied theoretically and experimentally, and the optimal conditions are determined for the integrated fluoride–ammonium ...recovery of different useful components. The enabling innovative technology is proposed for the production of amorphous silica, alumina, red iron oxide, calcium fluoride and other marketable products.
The research is aimed at revealing optimum physicochemical conditions for waste processing at coal-firing heat-power plants. The efficient technology has been developed for integrated extraction of ...amorphous silica, alumina, English red and other useful components.
The current technologies available in the world market for the chemical processing of caustobioliths of carbonic series are overviewed. The prospects for the expansion of the coal supply base in the ...Far East of Russia are discussed, and the main lines of advancement in the coal preparation industry are specified. It is possible to arrange coal chemistry clusters in the Amur Region (thermal conversion of coal, production of Montana wax and oxidized humite), in the Khabarovsk Territory (in-situ gasification) and in the Primorye (motor fuel and liquid fuel production).
Physicochemical processes of the fluoride processing of kyanite concentrates under the influence of additional components are studied theoretically and experimentally in the range of temperatures of ...20–550°C and curing times of 0.12–4.5 h. The optimal conditions of feed stock sintering with ammonium bifluoride, sublimation of ammonium hexafluorosilicate, formation of aluminum fluoride and alumina, and synthesis of amorphous silica nanoparticles are found. Thermodynamic and kinetic parameters of chemical reactions are calculated. The studies are used as a basis for the development of the fluoride method of alumina generation from kyanite concentrates with the complex recovery of other useful components.
