National University of Science and Technology «MISIS» (Moscow, Russia):

Yushina T. I., Head of Chair, Candidate of Engineering Sciences, Associate Professor, yushina.ti@misis.ru
Nguyen Van Trong, Trainee, nvtvast@mail.ru
Dumov A. M., Associate Professor, Candidate of Engineering Sciences, amark1@mail.ru
Nguyen Thu Thuy, Trainee, nttmisis@mail.ru

Sericite has extensive applications due to its specific physicochemical and insulating properties. The total output of sericite products is currently around 350 thousand tons per year and tends to increase by 1–3 % annually. In the Vietnamese province of Ha Tinh, sericite is concentrated in several economic ore bodies. The results of X-ray diffraction, mineralogical, and petrographic analyzes have demonstrated that quartz, sericite, and potassium feldspar account for 97–99 % of the original ore volume. Mineral aggregates are mainly represented by closely intergrown microparticles. The results of process experiments have shown that high-grade sericite concentrates may be recovered from the ore by selective grinding and classification in hydrocyclones. In 20 μm separation, the sericite concentrate yield was 26.94 %, which is 7.48 % higher as compared to 10 μm separation (19.46 %). The concentrate grade, however, was somewhat reduced: the mass fraction of SiO₂ in the –20 μm concentrate (52.44 %) was 2.83 % higher than that in the –10 μm concentrate (49.61 %) and the mass fraction of Al₂O₃ was 1.67 % lower in the –20 μm concentrate (32.76 %) than in the –10 μm concentrate (34.43 %). Selective flotation of –100+10 μm sericite middlings has confirmed the possibility of recovering granular sericite into a concentrate complying with the raw materials standards of a number of industries.

1. Pushcharovsky D. Yu. Structural mineralogy of silicates and their synthetic analogues. Moscow: Nedra, 1986. 160 p.
2. Vaisberg L. A., Kononov O. V., Ustinov I. D. Fundamentals of geometallurgy. St. Petersburg: Russkaya Kollektsiya, 2020. 376 p.
3. Minerals yearbook. U.S. Geological survey, 2007. URL: https://docplayer.net/7029489-2006-minerals-yearbook.html (accessed: 20.01.2022).
4. Nguyen Thi Thanh Thao. Characteristics of sericite ore etching in the formations of eruption of Dong Trau Formation in Hà TĨnh Region and usability. Hanoi: Mine Geological College, 2017.
5. Yushina T. I., Dumov A. M., Nguyen Van Trong, Nguyen Thu Thuy. Mineral composition and commercial application feasibility of sericite ore in Ha Tinh Province. Eurasian Mining. 2020. No. 2. pp. 32–38. DOI: 10.17580/em.2020.02.08.
6. Arsentiev V. A., Gerasimov A. M., Ustinov I. D. Resource-saving in processing of phyllosilicate minerals. Gornyi Zhurnal. 2018. No. 12. pp. 52–58. DOI: 10.17580/gzh.2018.12.11.
7. Wang Y. S., Alrefaci Y., Dai J. G. Silico-aluminophosphate and alkali-aluminosilicate geopolymers: a comparative review. Frontiers in Materials. 2019. Vol. 6. DOI: 10.3389/fmats.2019.00106.
8. Ossa-Moreno J., McIntyre N., Ali S., Smart J. C. R., Rivera D., Lall U., Keir G. The hydro-economics of mining. Ecological Economics. 2018. Vol. 145. pp. 368–379.
9. Nguyen M. T., Vink S., Ziemski M., Barrett D. J. Water and energy synergy and trade-off potentials in mine water management. Journal of Cleaner Production. 2014. Vol. 84. pp. 629–638.
10. Brichkin V. N., Kurtenkov R. V., Eldib A. B., Bormotov I. S. State and development options for the raw material base of aluminum in non-bauxite regions. Obogashchenie Rud. 2019. No. 4. pp. 16–20. DOI: 10.17580/or.2019.04.06.
11. Hongqaing L. I., Leming O. U., Feng Q., Chang Z. Recovery mechanisms of sericite in microcrystalline graphite flotation. Physicochemical Problems of Mineral Processing. 2015. Vol. 51, Iss. 2. pp. 387–400.
12. Vaisberg L. A., Ustinov I. D. Introduction to the technology of mineral separation. St. Petersburg: Russkaya Kollektsiya, 2019. 168 p.