Features of determining the specific surface area of powdered quartz-containing systems

Abstract

Introduction. Mineral raw materials, mechanically dispersed to a fine-grained condition, contribute to the effective use of the energy potential in the course of the structuring of composite materials. An important parameter, characterizing the dispersion ability and allowing to evaluate the ability of the system to transform is the specific surface of the substance. The experimental value of the specific surface depends on the measurement method and may differ for the same solids when different methods are applied. The purpose of the work is to study the morphological features of the surface of powdered quartz-containing systems having varying degrees of dispersion. The work represents the experimental identification of specific surface. Materials and methods. Filtration and adsorption methods were used to identify the specific surface of a mechanically activated sample of polymineral sand. Fine powders of sand were obtained by dry grinding in a planetary ball mill. The analysis of the obtained results was conducted taking into account the surface tension values of the powders as the characteristics of the surface energy of a surface area unit. Results. It is found that dimensions of the specific surface identified using the gas filtration method are smaller than those obtained using the nitrogen adsorption method. The authors have identified a linear functional dependence between the ratio of dispersion and polarization components of the surface tension and the ratio of specific surfaces obtained using different methods for one sample of sand. Conclusions. Despite a difference in the values obtained for the same material sample, specific surface area indicators, identified using different methods, allow to evaluate the extent of the surface maturity, the availability of active centres, and the energy potential of mineral powders. The ratio of specific surfaces can be used as a criterion for the rational choice of the operating parameters of mechanical activation of quartz-containing powder systems to increase the energy potential of the surface.