Numerical simulation for polycondensation of orthosilicic acid in hydrothermal solutions

Abstract

This paper describes numerical simulation of the polycondensation of orthosilicic acid in geothermal solutions under a variety of physical and chemical conditions, including temperature, pH, mineral content, and ionic strength. We obtained the concentrations of silica, oversaturation of the solution as a function of time, and the distribution of silica particles over size. It was found that the nucleation of orthosilicic acid and the origination of colloidal particles occurred at temperatures below 100–120°C. The relationships obtained here can be used for the technology of extracting silica from solutions with a prescribed particle size.