Improvement of colemanite flocculation with collectors by ultrasound treatment

Abstract

In this study, the influence of ultrasound on the stability of colemanite suspension was first studied without reagents, and the effects of ultrasound power value, treatment regime (batch and continuous), probe immersion depth, and treatment time on the suspension stability were determined. Then, the effects of ultrasound on the flocculation of colemanite with sodium dodecyl sulfate, Aero 845, and sodium oleate were investigated, and changes occurred in the flocculation efficiency, zeta potential and contact angle values were shown depending on the collector concentration. The experimental findings revealed that the application of ultrasound reduced the suspension stability; that is, enhanced flocculation of colemanite particles occurred due to the ultrasonic promotion. By the ultrasonic treatment, the contact angles measured on the mineral surface in the presence of these collectors increased. In addition, the ultrasonic treatment led to increases in the surface charge of colemanite mineral with these surfactants. These results indicated that the ultrasound increased the adsorption of collectors on the mineral surfaces, as a result of this, the hydrophobization of the colemanite surfaces improved, and thus the flocculation of colemanite enhanced.