Review of the current status and challenges for a holistic process-based description of mass transport and mineral reactivity in porous media

Abstract

Reactivity of minerals is controlled by chemical processes at mineral-fluid interfaces acting at different time- and length scales. Various modeling approaches are available to characterize scale-specific aspects of mineral-fluid interface chemistry. Most fundamental aspects of mineral reactivity are provided by atomic scale simulations. Several attempts have been made to interpret macroscopic observation based on atomic scale simulations alone. Many of them have failed however, because of neglecting the pore scale transport phenomena. Pore scale simulation, provide an elegant way to link idealized nanometer scale atomistic description of mineral reactivity with structural and compositional heterogeneities of natural systems. The main challenges are the spatial and temporal coupling of physical models and the upscaling of transport parameters for the macroscopic interpretation of the system behavior. This paper summarizes the current molecular-scale knowledge on mineral-fluid interface chemistry, obtained from complementary coarse-grain simulation approaches. Using the most recent developments in this field, we highlight the complexity and challenges of the pore-scale modeling and suggest a roadmap for the process-based description of mineral dissolution/precipitation across different scales.