Optimization of removal of calcium ions forming during synthesis of boric acid from ulexite ore by using ion exchange resin

Ulexite (Na2O·2CaO·5B2O3·16H2O) is one of the most important raw materials forboric acid, synthesized by dissolving the ore in an acid solution. Since ulexiteore was dissolved in a phosphoric acid solution, the final solution included boricacid (H3BO3), sodium dihydrogen phosphate [NaH2PO4], and calcium dihydrogenphosphate [Ca(H2PO4)2]. The presence of several ions in the solution causesseparation problems for boric acid. This study includes a special separation stepto increase the purity of the boric acid that is synthesized from the dissolution ofulexite ore in phosphoric acid. For this purpose, calcium ions in the final solutionwere removed using Dowex HCR-S cationic ion exchange resin. Additionally, theTaguchi optimization method was employed to monitor the removal of calciumions. The design of experiments included an orthogonal array technique in L9 arrayfor three parameters with three different values; reaction temperature (12 oC, 25oC, 40 oC), stirring rate (250 rpm, 300 rpm, 350 rpm), and the amount of resin(10% wt., 30% wt., 50% wt.). The results of the calculations revealed that theoptimum values of temperature, stirring rate, and amount of resin are 12 oC, 350rpm, and 50% wt., respectively. The amount of calcium removed under optimumconditions was found as 79.49%.

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İçelli O., Erzeneoğlu S., Boncukcuoğlu R., Measurement of X-ray transmission factors of some boron compounds, Radiat. Meas. 37, 613-616, 2003.
Künkül A., Yapici S., Kocakerim M. M., Copur M., Dissolution kinetics of ulexite in ammonia solutions saturated with CO2, Hydrometallurgy, 44, 135-145, 1997.
Tombal T. D., Özkan Ş. G., Ünver İ. K., Osmanlıoğlu A. E., Bor bileşiklerinin özellikleri, üretimi, kullanımı ve nükleer reactor teknolojisinde önem, BORON 1 (2), 86-95, 2016.
Budak A., Gönen M., Extraction of boric acid from colemanite mineral by supercritical carbon dioxide, J. Supercrit. Fluids, 92, 183-189, 2014.
Karagöz Ö., Kuşlu S., Dissolution kinetics of colemanite in potassium dihydrogen phosphate solution (KH2PO4), Int. J. Hydrogen Energy, 42, 23250-23259, 2017
Çelikoyan B., Bulutcu AN., Kolemanitten yeni bir yöntemle borik asit üretim prosesinin geliştirilmesi, ITU Dergisi/D Mühendislik, 9, 15-26, 2010.
Imamutdinova V. M., Rates of dissolution of native borates in H3PO4 solutions, J. Appl. Chem. USSR, 40, 2596-2598, 1967.
Temur H., Yartaşı A., Çopur M., Kocakerim M. M., The kinetics of dissolution of colemanite in H3PO4 solutions, Ind. Eng. Chem. Res., 39, 4114-4119, 2000.
Küçük Ö., Kocakerim M. M., Yartaşı A., Çopur M., Dissolution of kestelek’s colemanite containing clay minerals in water saturated with sulphur dioxide, Ind. Eng. Chem. Res., 41, 2853-2857, 2002.
Doğan H. T., Yartaşı A., Kinetic investigation of reac tion between ulexite ore and phosphoric acid, Hydrometallurgy, 96, 294-299, 2009.
Kizilca M., Copur M., Kinetic investigation of reaction between colemanite ore and methanol, Chem. Eng. Commun., 202, 1528-1534, 2015.
Küçük Ö., Application of Taguchi method in the optimization of dissolution of ulexite in NH4Cl solutions, Korean J. Chem. Eng., 23, 21-27, 2006.
Ekinci Z., Şayan E., Beşe A. V., Ata O. N., Optimization and modeling of boric acid extraction from colemanite in water saturated with carbon dioxide and sulphur dioxide gases, Int. J. Miner. Process., 82, 187-194, 2007.
Doğan T. H., Yartaşı A., Optimization of dissolution of ulexite in phosphate acid solutions, J.Chem.Soc.Pak., 36, 601-605, 2014.
Taguchi G., Introduction to quality engineering, New York: Mc Graw-Hill, 1990.
Çopur M., An optimization study of dissolution of Zn and Cu in ZnS concentrate with HNO3 solutions, Chem. Biochem. Eng., 15, 191-197, 2002
Scott W. W., Standard Methods of Chemical Analysis, Van Nostrand: New York, 1963.
Phadke M.S., Quality engineering using robust design, Prentice Hall: New Jersey, 61-292, 1989.
Roy R. K., A Primer on the Taguchi Method; Competitive Manufacturing Series, 1990.
Wu Y., Wu A., Taguchi methods for robust design, The Park Avenue, New York: The American Society of Mechanical Engineers, 2000