Batch process of silica precipitation was investigated experimentally and interpreted based on available theories and models. Silica was manufactured by neutralization of dilute sodium silicate solution with sulphuric acid in a baffled stirred tank reactor of diameter D-T=145 mm. Effects of pH, temperature, silica and electrolyte (NaCl) concentration were investigated. Particle size measurements were performed using a Malvern Zetasizer ZS ZEN 3500. Effects of process conditions on agglomeration of silica particles and stabilization of the silica nano-particle suspensions were interpreted using the DLVO based theories and models of surface composition. The stability ratio and surface composition were expressed in terms of the properties of the solution. Results of theoretical investigations together with experimental data show that effects resulting from colloidal forces including repulsion and attraction are not enough to explain aggregation phenomena and thus effects resulting from surface reactions should be considered in modeling as well. (C) 2012 Elsevier Ltd. All rights reserved.