Preparation of synthetic carnallite and amorphous silica from chromite beneficiation plant tailings
S. Top 1  
,   M. Yildirim 1  
 
More details
Hide details
1
Mining Engineering Department, Cukurova University, 01330, Adana, Turkey
 
Gospodarka Surowcami Mineralnymi – Mineral Resources Management 2017;33(2):5–23
 
KEYWORDS
ABSTRACT
In this paper, synthetic carnallite (MgCl2 ∙ KCl ∙ 6H2O) and amorphous silica (SiO2) preparation possibilities were investigated by utilizing chromite beneficiation plant tailings which contain 3.44% chromite (Cr2O3) and 30.55% magnesium oxide (MgO) by weight. Firstly, laboratory scale high intensity wet magnetic separator was applied for removing the magnetic materials such as chromite, iron (II ) and manganese (II ) minerals in the tailings. About 85.75% of chromite, 91.22% of MnO and 64.71% of Fe2O3 were removed by single stage magnetic separation. After the magnetic separation, hydrometallurgical recovery was initiated by leaching of the tailings with hydrochloric acid (HCl). Amorphous silica particles and the other solids were separated from the leach solution by filtration. Impurities were precipitated from the leach solution by elevating the solution pH via magnesiumhydroxide (Mg(OH )2) adding. The purified magnesium chloride (MgCl2) solution was mixed with potassium hydroxide (KOH ) at stoichiometric ratio. According to the XRD and chemical analysis, the synthetic carnallite was synthesized by controlled heating of this solution at 90–100°C. Also, the amorphous silica with 96.5% SiO2 content and 84.38% recovery yield was obtained by additional magnetic separation treatment.
METADATA IN OTHER LANGUAGES:
Polish
Wytwarzanie syntetycznego karnalitu i amorficznej krzemionki z odpadów wzbogacania rud chromitowych
karnalit syntetyczny, krzemionka bezpostaciowa, wzbogacanie magnetyczne, odzysk hydrometalurgiczny
W artykule przedstawiono badania możliwości wytwarzania karnalitu (MgCl2 • KCl• 6H2O) i bezpostaciowej krzemionki (SiO2) z odpadów z zakładów procesu wzbogacania chromitów, które zawierają 3,44% wag. chromitu (Cr2O3) i 30,55% wag. tlenku magnezu (MgO). W skali laboratoryjnej do usuwania materiałów magnetycznych, takich jak: chromit, żelazo (II) i minerały manganowe (II) zastosowano wzbogacanie mokre w separatorach magnetycznych o wysokiej intensywności. Około 85,75% chromitu, 91,22% MnO i 64,71% Fe2O3 usunięto metodą jednoetapowej separacji magnetycznej. Po wzbogacaniu magnetycznym odzysk hydrometalurgiczny został zainicjowany przez ługowanie odpadów kwasem chlorowodorowym (HCl). Amorficzne cząstki krzemionki i inne substancje stałe oddzielono od roztworu ługującego przez filtrację. Z roztworu ługowanego wytrąciły się zanieczyszczenia przez wzrost pH dzięki zawartemu wodorotlenkowi magnezu (Mg(OH)2). Oczyszczony roztwór chlorku magnezu (MgCl2) zmieszano z wodorotlenkiem potasu (KOH ) w stosunku stechiometrycznym. Zgodnie z XRD i analizą chemiczną, syntetyczny karnalit syntetyzowano przez kontrolowane ogrzewanie tego roztworu w temperaturze 90–100°C. Również odzysk 84,38% amorficznej krzemionki o zawartości 96,5% SiO2 uzyskano przez dodatkowe magnetyczne wzbogacanie.
 
REFERENCES (27)
1.
Agacayak et al. 2007 – Agacayak, T., Zedef, V. and Aydogan, S. 2007. Beneficiation of Low-grade Chromite Ores of Abandoned Mine at Topraktepe, Beyşehir, SW Turkey. Acta Montanistica Slovaka 12, pp. 323–327.
 
2.
Aslan, N. and Kaya, H. 2009. Beneficiation of Chromite Concentration Waste by Multi-Gravity Separator and High-Intensity Induced-Roll Magnetic Separator. The Arabian Journal for Science and Engineering 34(2B), pp. 285–297.
 
3.
Bron et al. 1967 – Bron, V.A., Stepanova, I.A. and Kudryavtseva, T.N. 1967. Effect of Degree of Serpentine Formation in Dunite on Its Properties and Structure Change During Heating. Refractories 8(9–10), pp. 553–558.
 
4.
Chen et al. 2014 – Chen, G., Wang, X., Du, H., Zhang, Y., Wang, J., Zheng, S. and Zhang, Y. 2014. A New Metallurgical Process for the Clean Utilization of Chromite Ore. International Journal of Mineral Processing 131, pp. 58–68.
 
5.
Cicek, T. and Cocen, I. 2002. Applicability of Mozley Gravity Separator (MGS) to Fine Chromite Tailings of Turkish Chromite Concentrating Plants. Minerals Engineering 15, pp. 91–93.
 
6.
Dutrizac et al. 2000 – Dutrizac, J.E., Chen, T.T. and White, C.W. 2000. Fundamentals of Serpentine Leaching in Hydrochloric Acid Media. [In:] Kaplan, H.I. et al. eds. Magnesium Technology 2000. Nashville, 2000. TMS (Mineral Metals Materials Society) Publication, pp. 41–52.
 
7.
El-leef et al. 2012 – El-leef, E.M.A., Abeidu, A.E.M., Mahdy, A.E.M. 2012. Utilization of Serpentine Ore for Production of Magnesium Sulphate. World Journal of Engineering and Pure & Applied Sciences 2(2), pp. 31–39.
 
8.
Fedorockova et al. 2012 – Fedorockova, A. Hreus, M. Racschman, P. and Sucik, G. 2012. Dissolution of Magnesium from Calcined Serpentinite in Hydrochloric Acid. Minerals Engineering 32, pp. 1–4.
 
9.
Gao et al. 2014 – Gao, W., Wen, J. and Li, Z. 2014. Dissolution Kinetics of Magnesium from Calcined Serpentine in NH4Cl Solution. Industrial & Engineering Chemistry Research 53(19), pp. 7947–7955.
 
10.
Geveci et al. 2002 – Geveci, A., Topkaya, Y. and Ayhan, E. 2002. Sulphuric Acid Leaching of Turkish Chromite Concentrate. Minerals Engineering 15(11), pp. 885–888.
 
11.
Gladikova et al. 2008 – Gladikova, L.A., Teterin, V.V. and Ovchinnikova, N.B. 2008. Purification of Magnesium Chloride Solution Used for Carnallite Synthesis. Russian Journal of Applied Chemistry 81(5), pp. 883–885.
 
12.
Guney et al. 2001 – Guney, A., Onal, G. and Atmaca, T. 2001. New Aspect of Chromite Gravity Tailings Re-processing. Minerals Engineering 14(11), pp. 1527–1530.
 
13.
Javed et al. 2010 – Javed, S.H., Naaved, S., Feroze, N., Zafar, M. and Shafaq, M. 2010. Crystal and Amorphous Silica from KMnO4 Treated and Untreated Rice Husk. Journal of Quality and Technology Management VI, pp. 81–90.
 
14.
Khattak et al. 2001 – Khattak, C.P., Joyce, D.B. and Schmid, F. 2001. Production of Solar Grade (SoG) Silicon by Refining Liquid Metallurgical Grade (MG) Silicon, National Renewable Energy Laboratory (NREL) – Subcontractor Final Report, 40 pp.
 
15.
Mindat.org. Mineral Information of Carnallite. [Online] Available at: http://www.mindat.org/min-906.... [Accessed: 13.12.2014].
 
16.
Mineral Research & Exploration General Directorate (MTA), Mineral Resources of Adana, [Online] Available at: http://www.mta.gov.tr/v2.0/tur... [Accessed: 21.02.2015].
 
17.
Mineralienatlas.de. Mineral Information of Carnallite. [Online] Available at: https://www.mineralienatlas.de... [Accessed: 13.11.2014].
 
18.
Polmear, I.J. 1999. Introduction: History, Production, Applications and Markets [In:] Avedesian, M.M. and Laker, H. eds. Magnesium and Magnesium Alloys. ASM International, Ohio, pp. 3–6.
 
19.
Spectroscopyonline.com. Quick and Easy Dissolution of Chromite Ores. [Online] Available at: http://www.spectroscopyonline.... [Accessed: 13.06.2014].
 
20.
Strelets, Kh.L. 1977. Electrolytic Production of Magnesium. Springfield, 325 pp.
 
21.
Teir et al. 2007 – Teir, S., Revitzer, H., Eloneva, S., Fogelholm, C.J. and Zevenhoven, R. 2007. Dissolution of Natural Serpentinite in Mineral and Organic Acids. International Journal of Mineral Processing 83, pp. 36–46.
 
22.
Top, S. and Yildirim, M. 2015. Magnesium Sulphate (MgSO4) Synthesis from Chromite Concentration Plant Tailings. Madencilik 54(1), pp. 37–46 (in Turkish).
 
23.
Tripathy et al. 2013 – Tripathy, S.K., Murthy, Y.R. and Singh, V. 2013. Characterization and Separation Studies of Indian Chromite Beneficiation Plant Tailing. International Journal of Mineral Processing 122, pp. 47–53.
 
24.
Vapur et al. 2014 – Vapur, H., Top, S., Demirci, S., Develi, Y. and Sirkeci, A.A. 2014. Investigation of the Enrichment Possibilities of Teckrom Mining Company Tailings. [In:] Ipekoglu, U. et al. eds. Proceedings of 14th International Mineral Processing Symposium. Kusadasi, 15–17 October, 2014. Turkish Mining Development Foundation, pp. 183–190.
 
25.
Watson et al. 2000 – Watson, K., Ficara, P., Charron, M., Peacey, J., Chin, E.W. and Bishop, G., The Magnola demonstration plant: A Valuable Investment in Technology Development and Improvement [In:] Kaplan, H.I. et al. eds. Magnesium Technology 2000. Nashville, 2000. TMS (Mineral Metals Materials Society) Publication, pp. 27–30.
 
26.
Xakalashe, B.S. and Tangstad, M. 2011. Silicon Processing: from Quartz to Crystalline Silicon Solar Cells [In:] Jones, R.T. and Hoed, P.D. eds. Southern African Pyrometallurgy 2011. Southern African Institute of Mining and Metallurgy, Johannesburg, pp. 83–99.
 
27.
Zengin et al. 2009 – Zengin, M., Gokmen, F., Yazici, M.A. and Gezgin, S. 2009. Effects of Potassium, Magnesium and Sulphur Containing Fertilizers on Yield and Quality of Sugar Beets (Beta vulgaris L.). Turkish Journal of Agriculture and Forestry 33, pp. 495–502.
 
eISSN:2299-2324
ISSN:0860-0953