Nitrik Asit Özütlemesi İle Doğal Manyezit Cevherinden Magnezyumun Çözünmesi

Manyezit (MgCO3) tuz tipi bir mineral olup Türkiye’de bol miktarda bulunur. Bu çalışmada manyezitin nitrik asit çözeltisi içindeki çözünürlüğü araştırılmıştır. Özütleme prosesi üzerine partikül boyutu, tepkime sıcaklığı, katı-sıvı oranı ve asit derişimi gibi parametrelerin etkileri incelenmiştir. Manyezit cevherinin çözünme hızının, tepkime sıcaklığı ve asit derişiminin artmasıyla ve katı-sıvı oranının azalmasıyla arttığı görülmüştür. Partikül boyutunun ise çözünme hızına önemli bir etkisi olmamıştır. Deneysel veriler kinetiğin, küçülen hacim modeline uyduğunu göstermiştir. Özütleme prosesinin aktivasyon enerjisi 3.24 kJ/mol olarak hesaplanmıştır.

Anahtar Kelimeler:

Manyezit; Nitrik asit; Çözünme; Özütleme; Kinetik

Dıssolutıon Of Magnesıum From Natural Magnesıte Ore By Nıtrıc Acıd Leachıng

Magnesite (MgCO3) is a salt-type mineral and is found in large amounts in Turkey. In this study, dissolution of magnesite in nitric acid solutions was investigated. The effects of various parameters such as particle size, reaction temperature, solid to liquid ratio and acid concentration on the leaching process were examined. It was determined that the dissolution rate of magnesite increased with increasing reaction temperature and acid concentration, and decreasing solid to liquid ratio. No significant effect of particle size was observed on the dissolution of magnesium. The experimental data fitted the shrinking core model. The activation energy of the leaching process was calculated as 3.24 kJ/mol

Keywords:

Magnesite; Nitric acid; Dissolution; Leaching; Kinetics.,

PDF

___

[1] D. Çakır, “Solid to Liquid Extraction of Magnesium Residue in Acidic Media”, Master of Science Thesis (in Turkish), Department of Chemical Engineering, Eskişehir Osmangazi University, Turkey, 2007.
[2] B. Bayrak, O. Laçin, H. Saraç, “Kinetic study on the leaching of calcined magnesite in gluconic acid solutions”, Journal of Industrial and Engineering Chemistry, Vol.16, pp.479-484, 2010.
[3] A. Fedorockova, P. Raschman, “Effects of pH and acid anions on the dissolution kinetics of MgO”, Chemical Engineering Journal, Vol. 143, pp.265-272, 2008.
[4] F. Demir, B. Dönmez, “Optimization of the dissolution of magnesite in citric acid solutions”, International Journal of Mineral Processing, Vol. 87, pp.60-64, 2008. [5] Y. Abalı, M. Çopur, M. Yavuz, “Determination of the optimum conditions for dissolution of magnesite with H2SO4 solutions”, Indian Journal of Chemical Technology, Vol. 13, pp.391-397, 2006.
[6] O. Laçin, B. Dönmez, F. Demir, “Dissolution kinetics of natural magnesite in acetic acid solutions”, International Journal of Mineral Processing, Vol. 75, pp.91-99, 2005.
[7] M. Özdemir, D. Çakır, İ. Kıpçak, “Magnesium recovery from magnesite tailings by acid leaching and production of magnesium chloride hexahydrate from leaching solution by evaporation”, International Journal of Mineral Processing, Vol.93, pp.209-212, 2009.
[8] H. Gülensoy, “Principle of Complexometry and Complexometric Titrations”, Istanbul University Publishing, Istanbul, Turkey, 1984.
[9] N. Demirkıran, “Dissolution kinetics of ulexite in ammonium nitrate solutions”, Hydrometallurgy, Vol. 95, pp.198-202, 2009.
[10] A. Ekmekyapar, N. Demirkıran, A. Künkül, “Dissolution kinetics of ulexite in acetic acid solutions”, Chemical engineering Research and Design, Vol. 86, pp.1011-1016, 2008.
[11] O. Levespiel, “Chemical Reaction Engineering”, 2nd ed., John Wiley and Sons: New York, 1999.
[12] W. Hsu, M. Lin, and J. Hsu, “Dissolution of solid particles in liquids:A shrinking core model”, International Journal of Chemical and Biological Engineering, Vol. 2:4, 2009.
[13] A. Kurtbaş, A. Ekmekyapar, S. Çolak, “Doğal manyezitin HCl çözeltileriyle heterojen reaksiyon kinetiği”, Doğa:Turk, Vol. 16, pp.90-94, 1992 (in Turkish).
[14] D. Uzun, “Dissolution kinetics of iron and aluminium from red mud in sulfuric acid solution”, Master of Science Thesis (in Turkish), Sakarya University, Turkey, 2006.
[15] Y. Zhang, M. Muhammed, “The removal of phosphorus from iron ore by leaching with nitric acid”, Hydromeatllurgy, Vol. 21, pp.255-275, 1989.