Factors influencing the porosity development during replacement reactions: a modeling approach

A critical aspect to consider during mineral replacement processes occurring by a dissolution-precipitation mechanism is the porosity evolution. The generation of porosity enables the progress of the replacement reaction, providing paths for the fluid to be in permanent contact with the reacting solid. On the contrast, if porosity does not form during the reaction, its advancement is hampered. This has enormous implications as it will determine, for example, the maximum capability of CO2 storage in a geological formation, the durability of cements in contact with aqueous solutions during long periods of time (in dams or radioactive waste disposal facilities), the long term performance of passive treatment systems for acid mine drainage remediation or the effectiveness of protective treatments for building stones based on replacing the original material by a secondary phase less soluble and thus more durable than the substrate.