Advances in the use of real-time molecular scale techniques to explore reaction mechanisms at the mineral/water interface


Donald L Sparks, and Michael J. Borda, Department of Plant and Soil Sciences, University of Delaware, 147 Townsend Hall, Newark, DE 19717
A detailed understanding of reaction rates at the mineral/water interface is critical to understanding the underlying reaction mechanisms that drive important processes in soils and aquifers such as sorption/desorption, dissolution/precipitation, and electron transfer. In many cases, a significant portion of the total reaction process may occur on rapid time scales of seconds to minutes. Such rapid reactions are difficult to capture using traditional batch and flow techniques. By using rapid-scan spectroscopic techniques one can study reaction processes in real-time and at the molecular level and determine important mechanistic information. Several of these techniques, including rapid-scan Fourier transform infrared (FTIR) and Quick X-ray absorption fine structure (Q-XAFS) spectroscopy, will be discussed and applied to study sorption and redox reactions on geosorbents.