Specific features of the physicochemical processes occurring in the interaction of kyanite concentrates with ammonium hydrodifluoride, sublimation of ammonium hexafluorosilicate, recovery of alumina ...and aluminum fluoride, synthesis of amorphous silica particles, and reduction of additional reagents were studied. The thermodynamic parameters, rate constants, and activation energies of the occurring chemical reactions were determined. The optimal conditions of the fluoride processing of kyanite concentrates with integrated recovery of various useful components were found.
Erratum to: Publisher’s Erratum Adushkin, V. V.; Kishkina, S. B.; Kulikov, V. I. ...
Journal of mining science,
2017/9, Letnik:
53, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Due to a technical error volume 53, issue 4, 2017 has been published online with an incorrect cover data. The issue has erroneously been distributed with the cover date July 2018. The correct caver ...date for volume 53, issue 4 should be July 2017.
Based on the physico-technical operations involved in the mineral processing technologies, the optimal production conditions are found for refractory fiber materials, aluminium, silicium, their ...compounds and other valued components. Ecologically safe and efficient aggregate technologies are developed for recovery of valued components from nonmetallic minerals and anthracides (brown coals).
We have studied the synthesis of amorphous silica nanoparticles through fluorination processing of quartz sand. The results demonstrate that synthesis conditions influence the physicochemical ...properties of the resultant amorphous silica. We have obtained silica-containing powders 17 to 89 nm in average particle size and 92 to 508 m
2
/g in specific surface area.
Based on physicochemical investigations into the processes of fluoride metallurgy, the optimal thermodynamic and kinetic conditions of processing kaolin concentrates favorable for the contrast ...distribution of compounds of aluminum and silicon over coexisting phases are revealed. As a result, the fluoride method for the complex recovery of alumina, aluminum, amorphous silica, silicon, and other useful components of the above-mentioned raw materials is developed. The industrial implementation of the new technology will extend the base of raw materials for the aluminum industry in the Russian Federation.
A study of amorphous silica generated from mineral material by the fluoride method and by different procedures of analysis, i.e., x-ray diffraction, x-ray fluorescence, IR spectroscopy, and nuclear ...magnetic resonance, is reported. Direct fluoridation of amorphous silica was performed by using gaseous F
2
and different conditions of processing, which allowed us to assess the reduction of impurities in amorphous silica and to show that (NH
4
)(Si(NH
3
)F
5
) was not present in the sample as an impurity.
The analysis of physical-chemical processing of silica-containing raw material has revealed optimal conditions for production of amorphous silica, ammonium hexafluorosilicate, mullite-siliceous ...refractory, and other commercial products. Using ammonium hydrodifluoride, the authors have developed efficient technologies for complex extraction of valuable components from silica-containing raw material.
An effect of ammonium hydrofluoride treatment of silica-containing raw material was examined. We described thermodynamics and kinetics of caking raw materials and their crushed materials, ammonium ...hexafluorosilicate sublimation, and amorphous silica formation. Constants of rate and activation energy of the chemical reactions were calculated.
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