Effect of CMC and pH on the Rheology of Suspensions of Isotropic and Anisotropic Minerals

Abstract

The rheology of mineral suspensions is highly dependent on the relationship between the mineral surface properties and inter-particle interactions as described by Derjaguin, Landau, Verwey and Overbeek (DLVO) theory. In this paper, the rheological properties of mineral suspensions are used to study the differences in behaviour of anisotropic talc and isotropic zircon minerals as a function of pH and polymer dosage (carboxymethyl cellulose, CMC). It was found that the rheological tests when carried out in parallel with electrophoretic or point of zero charge measurements clearly reveal differences between the behaviour of the suspensions of isotropic and anisotropic minerals. These differences are further accentuated with the addition of CMC.

The rheology of mineral suspensions is highly dependent on the relationship between the mineral surface properties and inter-particle interactions as described by Derjaguin, Landau, Verwey and Overbeek (DLVO) theory. In this paper, the rheological properties of mineral suspensions are used to study the differences in behaviour of anisotropic talc and isotropic zircon minerals as a function of pH and polymer dosage (carboxymethyl cellulose, CMC). It was found that the rheological tests when carried out in parallel with electrophoretic or point of zero charge measurements clearly reveal differences between the behaviour of the suspensions of isotropic and anisotropic minerals. These differences are further accentuated with the addition of CMC.

La rhéologie des suspensions de minéraux est extrêmement dépendante de la relation entre les propriétés superficielles du minéral et des interactions entre les particules, telle que décrite par la théorie de Derjaguin, Landau, Verwey et Overbeek (DLVO). Dans cet article, on utilise les propriétés rhéologiques des suspensions de minéraux pour étudier les différences de comportement du talc anisotrope et de minéraux isotropes de zircon en fonction du pH et du dosage de polymère (carboxyméthylcellulose, CMC). On a trouvé que les essais rhéologiques, lorsqu'effectués en parallèle avec des mesures électrophorétiques ou point de charge nulle, révélaient clairement les différences de comportement entre les suspensions de minéraux isotropes et anisotropes. Ces différences sont encore plus accentuées par l'addition de CMC.