par Stumm, Werner;Wollast, Roland 
Référence Reviews of geophysics, 28, 1, page (53-69)
Publication Publié, 1990-02
Référence Reviews of geophysics, 28, 1, page (53-69)
Publication Publié, 1990-02
Article révisé par les pairs
| Résumé : | Chemical weathering processes, essentially caused by the interaction of water and the atmosphere with the Earth's crust, transform primary minerals into solutes and clays and, eventually, into sedimentary rocks; these processes participate in controlling the global hydrogeochemical cycles of many elements. Many mineral dissolution processes are controlled by a chemical mechanism at the solid-water interface. The reactioncontrolling steps can be interpreted in terms of a surface coordination model. The tendency of a mineral to dissolve is influenced by the interaction of solutes - H +, OH -, ligands, and metal ions-with its surface. The surface reactivity is shown to depend on the surface species and their structural identity; specifically, the dependence of dissolution rates on pH and on dissolved ligand concentrations can be explained in terms of surface protonation (and deprotonation) and of ligand surface complexes. A general rate law for the dissolution of minerals is derived by considering, in addition to the surface coordination chemistry, established models of lattice statistics and activated complex theory. |
