Investigation of the surface properties of quartz-based dispersed materials

Abstract

Abstract Researched quartz disperses materials (Ukraine): mineral - quartzite of the Ovruch deposit and quartz sand of the Novovodolazsky deposit and products of processing of quartz minerals - dinas and marshalite. The mineral composition, surface morphology, dispersion and specific surface area were experimentally studied. The structure of the hydroxyl-hydrate surface layer was studied by thermogravimetric (TG) analysis and differential thermal analysis (DTA). The number and acid-base characteristics of surfaces active centers were investigated by the methods of pK-metric and pH-metric. It is established that the mechanisms of physical and chemical adsorption of water molecules on the surface of all quartz dispersed materials are identical and do not depend on the mineral nature of impurities. It is shown that the thickness of the surface hydroxyl-hydrate layer of quartz dispersed materials is determined by the amount of chemically adsorbed water, i.e. the thickness of the hydroxyl layer and depends on the nature of the associated minerals. It is established that the acid-base surface characteristic of quartz materials significantly depends on the chemical nature of the accompanying minerals and does not depend on the thickness of the surface hydroxyl-hydrate layer.