Effect of Microwave Irradiation on Physicochemical Properties of Ilmenite Surface

Document Type : Research Article


Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, I.R. IRAN


In this research, the microwave energy was used to modify the physicochemical properties of ilmenite surface for improvement of ilmenite floatability. The XPS analysis showed that microwave irradiation oxidizes the Fe2+ ions to Fe3+ ones; and the relative content of Fe3+ on the surface of ilmenite increases from 48.5% to 66%. This oxidation process decreases the ilmenite zeta potential; as its PZC (Point of Zero Charge) was changed from pH=5.4 to pH=3.0. The increase of Fe3+ ions increases the chemisorption of oleate ions on the surface of ilmenite; and results in the formation of more insoluble ferric iron oleate. The maximum adsorption of oleate ions occurs at a pH range of 6-7. After microwave irradiation the measured contact angle of ilmenite increases from 91 to 96 degrees. After oleate adsorption, the surface zeta potential of non-irradiated and irradiated ilmenite is obtained -66.3 mV and -78.1 mV, respectively. Thus, the changes in the physicochemical properties of ilmenite occurred by microwave irradiation improves the hydrophobicity and floatability of ilmenite in a wide pH range.


Main Subjects

[1] Nayl A.A., Ismail I.M., Aly H.F., Ammonium Hydroxide Decomposition of Ilmenite Slag, Hydrometallurgy, 98: 196- 200 (2009).
[2] Nayl A., Awwad N., Aly H., Kinetics of Acid Leaching of Ilmenite Decomposed by KOH, Leaching by H2SO4 and C2H2O4,Part 2, Journal of Hazardous Materials, 168: 793-799 (2009).
[4] اسم­خانی، رحیم؛ قبادی، بهمن؛ امیرخانی، اکبر؛ امین­خانی، علی؛ شناسایی نمونه گل قرمز کارخانه تولید آلومینای جاجرم و مطالعه روش های بازیابی تیتانیم دی اکسید از آن، نشریه شیمی و مهندسی شیمی ایران، (2)27 : 59 تا 66 (1387).
[5] Kothari N., Recent Developments in Processing Ilmenite for Titanium., International Journal of Mineral Processing, 1: 287- 305 (1974).
[6] Fan X., Rowson N., The Effect of Pb (NO3) 2 on Ilmenite Flotation,Minerals Engineering, 13: 205- 215 (2000).
[7] Pryor E.J., “Mineral Processing”, E3, 3rd ed, Amsterdam, Great Yarmouth Printed, (1965).
[8] Fan X., Kristian E.W., Rowson N., Parkera D.J., Modification of Ilmenite Surface Chemistry for Enhancing Surfactants Adsorption and Bubble Attachment, Journal of Colloid and Interface Science, 329: 167- 172 (2009).
[9] Song Q., Tsai S.C., Flotation of Ilmenite Using Benzyl Arsonic Acid and Acidified Sodium Silicate, International Journal of Mineral Processing, 26: 111- 121 (1989).
[10] رضایی،بهرام؛ "فلوتاسیون"، انتشارات دانشگاه هرمزگان، (1378).
[11] مالکی­مقدم، مصطفی؛ سام، عباس؛ حاجی امین شیرازی، حسن؛ بررسی فعال­سازی سطحی و پالایش اسیدی در بازیابی کانی ایلمنیت، نشریه شیمی و مهندسی شیمی ایران، (1)31 : 88 - 81 (1391).
[12] Chen T., Dutrizac J.E., Haque K.E., Wyslouzil W., Kashyap S., The Relative Transparency of Minerals to Microwave Radiation, Canadian Metallurgical Quarterly, 23: 349- 351 (1984).
[13] Meredith R.R.J., “Engineers Handbook of Industrial Microwave Heating”, IET, (1998).
[14] Kingman S., Jacksona K., Bradshaw S.M., An Investigation Into the Influence of Microwave Treatment on Mineral ore Comminution, Powder technology, 146: 176- 184 (2004).
[15] George C., Rao G., Thalakola V., Thermal Desorption of Contaminants Using Microwave Heated Rotary Mixture, in: "Proceedings of the 29th Microwave Power Symposium", Chicago, IL.(1994).
[16] Kobusheshe J., "Microwave Enhanced Processing of Ores", University of Nottingham. (2010).
[17] Metaxas A.A., Meredith R.J., "Industrial Microwave Heating", Peter Peregrinus LTD, The Institution of Electrical Engineers, London, United Kingdom, )1983(.
[18] Fan X., Rowson N., Fundamental Investigation of Microwave Pretreatment on the Flotation of Massive Ilmenite Ores, Developments in Chemical Engineering and Mineral Processing, 8: 167- 182 (2000).
[19] Galema S.A., Microwave Chemistry, Chem. Soc. Rev, 26: 233- 238 (1997).
[20] Botsco R., Cribbs R.W., Mcmaster R., "Nondestructive Testing Handbook", Vol 4. E2, Editor: R.C McMaster, Ameircan Society for Nondestructive Testing, (1986)
[21] Von Hippel A., "Dielectric Materials and Applications", Technology Press of M.I.T., John Wiley and Sons, New York, (1954).
[22] مهدیلو، اکبر؛ "مطالعات کانه‌آرایی کانسنگ تیتانیم قره‌آغاج به روش‌های فیزیکی"، پایان نامه کارشناسی ارشد، دانشگاه صنعتی امیر کبیر تهران (1382).
[23] Zhu Y., Zhang G.F., Feng Q.M., Effect of Surface Dissolution on Flotation Separation of Fine Ilmenite from Titanaugite, Trans. Nonferrous Met. Soc. China., 21: 1149- 1154 (2011).
[24] Thostenson E., Chou T.W., Microwave Processing Fundamentals and Applications. Composites Part A, Applied Science and Manufacturing, 30: 1055- 1071 (1999).
[25] Mehdilo A., Irannajad M., Rezai B., Effect of Chemical Composition and Crystal Chemistry on the Zeta Potential of Ilmenite, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 428: 111-119 (2013).