Effect of Chloride Salt Ions onto Coal Flotation based on Contact Angle and Bubble-Particle Attachment Time


Creative Commons License

GÜNGÖREN C., BAKTARHAN Y., ŞAHBAZ O., KURSUN I., ÖZKAN Ş. G., ÖZDEMİR O.

Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi, vol.24, no.71, pp.553-562, 2022 (Peer-Reviewed Journal) identifier

Abstract

This study was aimed to reveal the effect of K+, Na+, Ca2+, and Mg2+ ions on the bubble-particle interactions of high-rank coal with contact angle and bubble-particle attachment time studies. The results for the contact angle experiments indicated that the contact angle of the coal, which was 62° in the absence of ions, increased slightly in the presence of mono- and divalent ions and reached a maximum (67°) in the presence of 1∙10-1 mol/dm3 Mg2+, and the effect of K+ ions on the contact angle was minimal. Furthermore, the results for the bubble-particle attachment time experiments showed that the bubble-particle attachment time of coal, which was measured as 4.5 ms in the absence of ions, decreased as a function of ion concentration from 1∙10-2 mol/dm3 to 1 mol/dm3. While the bubble particle attachment times of coal particles in the presence of K+/Na+ and Ca2+/Mg2+ at low concentrations were around 2-3 ms and 1-2 ms, respectively, the increase in the concentration slightly changed the attachment time which decreased to less than 1 ms except for K+ ions. Overall, it can be concluded from this study that the effect of these dissolved ions in water was more prominent on the bubble-particle attachment time of the coal particles rather than the contact angle which showed no significant change. Also, the specific ion effect was determined as “Mg2+ > Ca2+ > Na+ > K+” in terms of the bubble-particle interactions in the presence of these ions. Keywords: Chloride Salt Ions, Coal, Flotation, Bubble-Particle Attachment Time, Contact Angle