Polydispersity Effect and Coagulation Structures on the Surface Tension of Isotherms for Bentonite Suspensions

Abstract

The paper presents the results of an experimental study considering the dependence of the surface tension of bentonite aqueous suspensions on the concentration of the solid phase and the time of the surface formation. To conduct experimental studies, a new technique has been developed, which allows leveling the influence of the sedimentation factor on the magnitude of the surface tension. A distinctive feature of the proposed technique is that these methods of measuring surface tension are used for the first time. In this method the process of sedimentation is multidirectional relative to the surface. The results obtained allowed us to determine that the resulting coagulation structures have a significant influence on the nature of changes in the surface tension of bentonite aqueous suspensions. It was established that the polydispersity of the solid phase and water molecules in the dispersion medium play a key role in the formation of spatial structures and, as a consequence, in the formation of a minimum on the surface tension isotherms of bentonite suspensions.