The Conversion Kinetics of Tincal to Boric Acid in Nitric Acid Solutions

Document Type : Research Article


1 Department of Chemistry, Yüzüncüyıl University, Van, TURKEY

2 Department of Chemical Engineering, Engineering Faculty, Çankırı Karatekin University, Çankırı, TURKEY

3 Department of Chemical Engineering, Engineering Faculty, Bursa Teknik University, Bursa, TURKEY

4 Department of Metallurgy and Material Engineering, Engineering Faculty, Bilecik Şeyh Edebali University, TURKEY


Pure borax and various boron compounds are produced from the solutions in which tincal is dissolved with various reagents. Economically important boron compounds such as boric acid, borax, boric oxide, and refined hydrated sodium borates and perborates are produced from boron-containing ores. The production of boric acid by using nitric acid from tincal is more advantageous because it evaluates by-product NaNO3 as fertilizer production. In this study, the conversion kinetics of tincal to boric acid in nitric acid solutions were investigated by such parameters as particle size, 300-1500 µm; acid concentration,0.5-4 mol/L; solid-to-liquid ratio 0.04-0.10 g/mL; stirring speed 20.93-62.8  s-1, and reaction temperature, 30-60 oC. The conversion was found to increase with decreasing particle size and solid-to-liquid ratio and while it increased with increasing reaction temperature, acid concentration, and stirring speed. The conversion kinetics was examined using the heterogeneous and pseudo-homogeneous reaction models. The experimental results were found to be in better agreement with the correlation given in the following equation and the activation energy being 37.5 kJ/mol.  


Main Subjects

[1] Garret D.E., “Borates: Handbook of Deposits, Processing, Properties, and Use”, Academic Press Ltd, New York NY, (1998)
[2] Kemp H.P., “The Chemistry of Borates: Part I” Borax Consolidated Ltd., London, (1956)
[3] Sınırkaya M., Kocakerim M.M., Boncukçuoğlu R., Küçük Ö., Öncel S., Recovery of Boron from Tincal Wastes, Industrial Engineering Chemistry Research,  44 (3); 427-433 (2005)
[4] Celeste M., Azevedo C., Cavaleiro M.V., The Acid–Base Titration of a Very Weak Acid: Boric Acid, Journal of Chemical Education, 89(6): 767-770 (2012).
[5] Imamutdinova V.M., Bikchurova A. Kh., Imamutdinova V.M., Bikchurova A. Kh., Kinetics
of Dissolving Borates in HNO3 Solutions, Zhurnal Pikladnoi Khimii, 40 (7):1616-1618, (1967).
[6] Zdonovskii A.B., Imamutdinova V.M., Rate of Solution of Natural Borates in HCl Solutions, Zhurnal Pikladnoi Khimii, 36 (8): 1675-1680 (1963)
[7] Kononova G.N., Nozhko E.S., Nature of the Sulfuric Acid Dissolution of Magnesium Borates, Zhurnal Pikladnoi Khimii, 54(2): 397-399 (1981).
[8] Karazhanov N.A., The Kinetics of the Dissolution of Borates and Other Natural Salts, Zhurnal Pikladnoi Khimii, 36(12): 2642-2649 (1963).
[9] Imamutdinova V.M., Vladykina A.N., Rate of Decomposition Native Borates in Perchloric Acid Solutions, Zhurnal Pikladnoi Khimii, 42(5): 1172-1175 (1969).
[10] Zdanovskii A.B., Biktogirova L.G., Mechanism of Decomposition of Calcium Borates in H3PO4 Solutions, Zhurnal Pikladnoi Khimii, 40 (12): 2659-2663 (1967).
[11] Imamutdinova V.M., Abdrashitova N., Rate of Dissolution of Borates in Acetic Acid Solutions, Zhurnal Pikladnoi Khimii, 43 (2): 452-455 (1970).
[12] Yeşilyurt M., Determination of the Optimum Conditions for the Boric Acid Extraction from Colemanite Ore in HNO3 Solutions, Chemical Engineering and Processing, 43(10): 1189-1194 (2004).
[13] Gülensoy H., Kocakerim M.M.,  Solubility of Ulexite Mineral in CO2- Containing Water, Bulletin of The Mineral Research and Exploration, 89: 36-41 (1977)
[14] Gülensoy H., Kocakerim M.M., Solubility of Colemanite Mineral in CO2-Containing Water and Geological Formation of This Mineral, Bulletin of The Mineral Research and Exploration, 90: 19 (1978).
[15] Yapıcı S., Kocakerim M.M., Künkül A., Optimization of production of H3BO3 from ulexite, Turkish Journal of Engineering and Environmental Sciences, 18: 91-94 (1990).
[16] Künkül A., Yapıcı., Kocakerim M.M., Çopur M., Dissolution Kinetics of Ulexite in Ammonia Solutions Saturated with CO2, Hydrometalurgy, 44: 135-145 (1997).
[17] Kocakerim M.M., Alkan., Dissolution Kinetics of Colemanite in SO2-Saturated Water, Hydrometallurgy, 19: 385-392 (1988)
[18] Özmetin C., Kocakerim M.M., Yapıcı., Yartaşı A., Semiempirical Kinetic Model for Dissolution of Colemanite in Aqueous CH3COOH Solutions, Industrial Engineering Chemistry Research35 (7): 2355-2359 (1996).
[19] Tunç M., Yapıcı S., Kocakerim M.M., Yartaşı A., The Dissolution Kinetics of Ulexite in Sulfuric Acid Solutions, Chemical and Biochemical Engineering Quarterly, 15(4): 175-180 (2001).
[20] Tunç M., Kocakerim M.M., Gür A., Yartaşı A.,
A Semiempirical Kinetic Model for Dissolution of Ulexite in Aqueous Acetic Acid Solutions, Energy, Education, Science and Techonology, 3(1): 1-10 (1999)
[21] Tunç M., Gür A., Kocakerim M.M., Yartaşı A., Dissolution of Ulexite in Sulfuric Acid Solutions for High Solid-to-Liquid Ratios, Energy, Education, Science and Technology, 3(1): 32-41 (1999).
[22] Künkül A., Tunç M., Yapıcı S., Erşahan H., Kocakerim M.M., Dissolution of thermally dehydrated ulexite in sulfuric acid solution, Industrial Engineering Chemistry Research, 36; 4847-4851 (1997)
[23] Tunc M., Kocakerim M.M., Yapıcı S., Bayrakçeken S., Dissolution mechanism of ulexite in H2SO4 solution, Hydrometallurgy, 51; 359-370 (1999)
[24] Tunç M., Çelik C., Çolak S., Kocakerim M.M., Determination of optimum conditions for dissolution of ulexite in sulfuric acid solutions, Mineral Processing and Extractive Metallurgy, Section C, 108; 48-52 (1999)
[25] Tunç M., Mermerci N., Yeşilyurt M., Kocakerim, M.M., Çolak S., Dissolution kinetics of borax in acetic acid solutions, Proceedings of 3rd International boron symposium, 199-202, 02-04 November 2006 Ankara, Turkiye.
[26] Tunc M., Kocakerim M.M., Küçük Ö., Aluz M., Dissolution of colemanite in (NH4)2SO4 solutions, Korean Journal of Chemical Engineering, 24(1); 55-59 (2007)
[27] Mergen A., Demirhan M.H., Bilen M., Fabrication of boric acid and sodium sulfate from borax, Ceramic Forum International. 81(3); 37-42 (2004) 
[28] Mergen A., Demirhan M.H., Bilen M., Gündüz M., Production of sodium sulfate as a by-product during boric acid fabrication from borax, Silicates Industrials, 69(11-12); 87-92 (2004)
[29] Mergen A., Demirhan M.H., Bilen M., Processing of Boric Acid from Borax by a Wet Chemical Method, Advanced Powder Technology, 14(3); 279-293 (2003)
[31] Nezhad B.Z., Monteghian M., Tavare N.S., On the confluence of dissolution, reaction and precipitation: The case of  boric acid, Chemical Engineering Science, 51(11); 2547-2552 (1996)
[32] Levensipel O., “Chemical Reaction Engineering”, 3rd edition, Jone Wiley & Sons, Inc., New York, 566-586 (1999)
[33] Karagölge Z., Alkan M., Kocakerim M.M., Leaching Kinetics of colemanite by aqueous EDTA solutions, Metallurgical Transactions B, 23B; 409-413 (1992)