Navoi State Mining Institute (Navoi, Republic of Uzbekistan):

Umirov F. E., Professor, Doctor of Engineering Sciences, umirov3@yandex.ru
Shodikulov Zh. M., Doctoral Student, shodiqulov_jurabek@mail.ru

Despite its widespread magnesium-containing deposits, Uzbekistan is still importing the major part of magnesium-containing raw materials used. In a market economy, it is extremely urgent for Uzbekistan to establish the supply of magnesium compounds to meet the demand of the domestic market using the reserves of its local deposits. The composition and properties of serpentinites of the Karmaninskoe deposit were studied using a set of physicochemical analysismethods. It has been established for the first time that the main rock-forming minerals for these serpentinites are antigorite (60 %), nepouite (22 %), talc (15 %), and additional franklinite (2 %), magnesite, and magnetite (an ore mineral), with microinclusions of chromite (0.5–1 %). The sample analysis results indicate that calcination of these minerals causes the separation of impurities with the exhaust gases. It has been shown that the mass fraction of magnesium oxide in the initial serpentinites was approximately 30 %. Their solubility was established depending on the particle size and properties of the solvents used. It has been found that acid treatment may be effectively used to decompose the magnesium-silicate bonds in those samples that had been previously considered thermally stable even at 800 °C. The studies of serpentinites of the Karmaninskoe deposit have therefore confirmed their applicability not only in the original form for making heat-resistant ceramics and heat-insulating building materials, but also as a raw material for obtaining magnesium chlorate, used as a defoliant for pre-harvesting removal of cotton leaves in mechanized cotton harvesting.

1. Karapet'yants M. Kh., Drakin S. I. General and inorganic chemistry. Moscow: Khimiya, 2000. 592 p.
2. Bryanchaninova N. I., Makeev A. B. Serpentinites of the Polar Urals. What are they like. Vestnik Instituta Geologii Komi Nauchnogo Tsentra Uralskogo Otdeleniya RAN. 2004. No. 2. pp. 15–19.
3. Smirnova O. A., Bugakov S. V. Production of synthetic serpentinite. Collection of scientific papers based on the materials of the International scientific and practical conference, Tambov, April 30, 2014. pp. 132–133.
4. Chen T. T., Dutrizac J. E., White C. W. Serpentine ore microtextures occurring in the magnola magnesium process. JOM: Journal of Minerals, Metals & Materials Society. 2000. Vol. 52. pp. 20–22.
5. Nazarova L. N., Khusnutdinov V. A. Obtaining liquid glass from serpentinite. Vestnik Kazanskogo Tekhnologicheskogo Universiteta. 2003. No. 1. pp. 57–59.
6. Perederin Yu. V., Usoltseva I. O., Krasnoshchekova D. V. Basic technologies for obtaining magnesium oxide from serpentinite. Polzunovskiy Vestnik. 2019. No. 2. pp. 123–127.
7. Kameneva E. E., Lebedeva G. A., Sokolov V. I., Frolov P. V. Study of the material composition and technological properties of Karelia serpentinites. Materials of the annual meeting of the Russian Mineralogical Society. St. Petersburg, 2006. pp. 22–24.
8. Osadchenko I. M., Lyabin M. P., Romanovskova A. D. Magnesium oxide: properties, methods of preparation and application (analytical review). Prirodnye Sistemy i Resursy. 2018. Vol. 8, No. 3. pp. 5–14.
9. Carmignano O., Vieira S., Brandao P., Bertoli A., Lago R. Serpentinites: mineral structure, properties and technological applications. Journal of the Brazilian Chemical Society. 2019. Vol. 31, Iss.1. pp. 1–13.
10. Hirauchi K., Nagata Y., Kataoka K., Oyanagi R., Okamoto A., Michibayashi K. Cataclastic and crystal-plastic deformation in shallow mantle-wedge serpentinite controlled by cyclic changes in pore fluid pressures. Earth and Planetary Science Letters. 2021. Vol. 576. pp. 117–232.
11. Navarro R., Pereiraab D., Fernández de Arévalo E., Sebastián-Pardod E. M., Rodriguez-Navarrod C. Weathering of serpentinite stone due to in situ generation of calcium and magnesium sulfates. Construction and Building Materials. 2021. Vol. 280. pp. 122–402.
12. Averina G. F., Chernykh T. N., Orlov A. A., Kramar L. Ya. Research of interrelation between volume deformation, composition and structural characteristics of magnesia binding materials. Vestnik Yuzhno-Uralskogo Gosudarstvennogo Universiteta. Seriya: Stroitelstvo i Arkhitektura. 2017. Vol. 17, No. 3. pp. 40–47.
13. Khamidov R. A. Panchenkova L. A. Resources of magnesia refractory raw materials of Uzbekistan. Geologiya va Mineral Resurslar. 2000. No. 3. pp. 25–27.
14. Federov N. F., Andreev M. A., Khartukova A. A. Binder compositions based on mixtures of heat-treated serpentinite and aqueous solutions of rare earth nitrates. Zhurnal Prikladnoy Khimii. 2006. Vol. 79, No. 7. pp. 1226а–1226.
15. Umirov F. E., Shodikulov Zh. M., Umirov U. F. Research of processes of obtaining chlorate-magnesium defoliant on the basis of serpentinite of the Arvaten deposit. Put' Nauki (The Way of Science). 2020. No. 10. pp. 19–22.
16. Zyryanov V. A. Features of the mineral composition of serpentinites in the zones of complex veins at the deposits of chrysotile-asbestos of the Bazhenov subtype. Vestnik Uralskogo Otdeleniya Rossiyskogo Mineralogicheskogo Obshchestva. 2008. No. 5. pp. 36–42.
17. Umirov F. E., Nomozova G. R., Shodiqulov J. M. Physicochemical properties and agrochemical effectiveness of new defoliants based on sodium, magnesium and calcium chlorates containing surfactants. Universum: Khimiya i Biologiya. 2021. No. 1–1. pp. 90–95.
18. Khanin D. A., Zakharov A.V. Unusual mineralization of quartz vein in serpentinites of Lipovsky deposit (Middle Urals). Vestnik Uralskogo Otdeleniya Rossiyskogo Mineralogicheskogo Obshchestva. 2013. No. 10. pp. 124–126.
19. Kisner A. S., Pashchenko N. V., Vakalova T. V. Magnesia-silicate ceramic materials based on Khakass serpentinites. Proc. of the International conference, Tomsk, October 09–13, 2017. pp. 320–321.
20. Zulumyan N. O., Oganesyan E. B., Oganesyan Z. G., Karakhanyan S. S. On the thermal acid treatment of serpentinites of the northeastern coast of Lake Sevan. Doklady Natsionalnoy Akademii Nauk Respubliki Armeniya. Neorganicheskaya Khimiya. 2002. Vol. 102, No. 3. pp. 55–58.
21. Gabdullin A. N., Kalinichenko I. I., Pecherskikh E. G., Semenishchev V. S. Obtaining of highly dispersed silica by the method of nitric acid processing of serpentinite. Uchenye Zapiski Tavricheskogo Natsionalnogo Universiteta im. V. I. Vernadskogo. Seriya: Biologiya, Khimiya. 2011. Vol. 24, No. 3. pp. 44–47.
22. Pat. 2285666 Russian Federation.
23. Umirov F. E, Fayzullaev N. I., Usanbayev N. Kh., Muzaffarov A. M., Umirov U. F., Pirnazarov F. G. Mineralogical and technological evaluation of saponites of the Uchtut residential place in the Republic of Uzbekistan. International Journal of Control and Automation. 2020. Vol. 13, No. 4. pp. 230–236.
24. Döbelin N., Kleeberg R. Profex: a graphical user interface for the Rietveld refinement program BGMN. Journal of Applied Crystallography. 2015. Vol. 48. pp. 1573–1580.
25. Gabdullin A. N. Development of a method for nitric acid processing of serpentinite from the Bazhenov deposit: dis. for the degree of Candidate of Engineering Sciences. Ekaterinburg, 2015. 135 p.
26. Vladimirov A. S., Katyshev S. F., Teslyuk L. M. Improvement of the washing process of amorphous silicon dioxide obtained by hydrochloric acid leaching of serpentinite. Khimicheskaya Tekhnologiya. 2015. Vol. 16, No. 3. pp. 139–141.