The effects of grinding on the physicochemical characteristics of white sepiolite from Golesh

Abstract

The influence of grinding white sepiolites from the Magure-Golesh mine in Southern Serbia on their structure and on the rheological characteristics of their aqueous suspensions was investigated. Sepiolite samples of hard and soft consistency were ground in three different types of mills: a ball mill, air-stream mill, and a colloid mill. The effect of grinding on the sepiolite samples was investigated by SEM, XRD, IR, TG and BET methods and by chemical analysis. Grinding generally resulted in the separation of the sepiolite fibers, and partial amorphization. In addition, grinding produced substantial changes in the apparent viscosity and rheological characteristics of dilute aqueous suspensions of sepiolite. It is concluded that the viscosities are especially affected by the type of grinding employed.