Aluminosilicate dissolution kinetics: a general stochastic model.

We apply a kinetic model developed for understanding the behavior of crystal dissolution to aluminosilicate dissolution kinetics. Without making any assumptions about specific dissolution mechanisms, the model is a vigorous stochastic exploration of all of the elementary reactions and basic processes involved in dissolution: bond breakage, bond formation, surface diffusion, and departure and arrival of Si- and Al- units. In the stochastic model, the interdependence of these elementary reactions and basic processes is strictly determined by the complicated three-dimensional surface structure in which interconnected Si- and Al- atoms share oxygen atoms. The modeling results are consistent with experimental data in various aspects, such as saturation state dependence of the dissolution rate, aluminum inhibition effects, surface chemistry evolution, anisotropic dissolution, and alteration product. The stochastic model integrates all microscopic information at the atomic scale and elucidates the reasons for the observed kinetic results in experimental studies, improving our fundamental understanding of aluminosilicate dissolution.