Numerical Simulation of the Polycondensation of Orthosilicic Acid and of the Formation of Silica Particles in Hydrothermal Solutions

Abstract

This paper reports numerical modeling work for the polycondensation of orthosilicic acid (OSA) and the growth of the number of silica particles (SiO₂) in hydrothermal solutions under a variety of physical and chemical conditions: temperature, pH, ionic strength, etc. We have derived relationships to calculate the concentration of orthosilicic acid and the mean radii of silica particles in relation to time and made plots showing the distribution of particles over size. The results were compared with experimental data. This study is important for investigating the role of colloidal silica in hydrothermal mineralization and for practical extraction and applications of silica, as well as for synthesis of minerals.