Effect of ultrasound on the dispersion of kaolinite and sepiolite suspensions with and without sodium silicate

Document Type : Research Paper


Department of Mining Engineering, Faculty of Engineering and Natural Sciences, Konya Technical University (KTUN), Konya, Turkey



In this study, the effect of the ultrasound process on the dispersion of kaolinite and sepiolite suspensions in the absence and presence of sodium silicate was investigated. The effects of ultrasonic device-dependent parameters such as power, treatment time, and application method (batch and continuous) on the dispersion of kaolinite and sepiolite suspensions were determined. Results of the studies carried out without sodium silicate showed the suspension stability values of kaolinite and sepiolite minerals presented some differences. While the stability of the kaolinite suspension decreased at high power ultrasonic values, it increased slightly for the mineral sepiolite. Also, the stability of the kaolinite suspension decreased, while the stability of sepiolite increased with a prolonged ultrasonic treatment time. It was also found that the application of ultrasound did not affect the isoelectric point (iep) of these clay minerals. In the presence of sodium silicate as a dispersant, the dispersion of these mineral suspensions increased depending on ultrasonic power and treatment time. Moreover, higher suspension stability values were obtained with the ultrasound application. In addition, the negative zeta potential values of clays after ultrasonic treatment were higher than those without ultrasound. The findings obtained showed that kaolinite and sepiolite suspensions were more successfully dispersed by ultrasonic treatment.

Graphical Abstract

Effect of ultrasound on the dispersion of kaolinite and sepiolite suspensions with and without sodium silicate


  • The effect of ultrasound process on the dispersion of kaolinite and sepiolite suspensions was studied.
  • The ultrasonic had no effect on the isoelectric point of clay minerals.
  • The ultrasonic treatment improved the dispersion of kaolinite and sepiolite with sodium silicate.
  • The ultrasonic treatment led to more negative zeta potentials for kaolinite and sepiolite.


Main Subjects

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