The Role of Interfacial Processes on Mineral Transformations in Wet Supercritical CO2
EMSL Project ID
37193
Abstract
We propose a comprehensive experimental and theoretical investigation of the role of interfacial water and CO2 on the energies, mechanisms, and rates of reactivity of a series of orthosilicate and phyllosilicate minerals in contact with supercritical-CO2 (scCO2) containing variable H2O. The molecular mechanisms for carbonation reactions, as well as the distribution of H2O between scCO2 and mineral surfaces, will be followed using molecular simulations and surface spectroscopy as a function of T, P, mineral composition and structure, and aH2O. The dynamics of water reactivity will be simulated using newly developed molecular dynamics models and reaction barriers will be calculated using density functional and molecular orbital theory electronic structure methods. The theoretical studies will be coupled with high-resolution spectroscopic measurements (e.g., IR/FTIR, NMR) to investigate the formation and structure of water layers at mineral surfaces and in the interlayer region of phyllosilicates, and identify potential interfacial carbonate and silicate species. The macroscopic reactivity of the orthosilicates and the changes in interlayer water structure and reactivity of the phyllosilicates will be determined experimentally using high pressure cells. The proposed research will provide new insights into mineral transformations under extreme conditions and help establish a basis for assessing the effectiveness of CO2 sequestration in geologic disposal sites.
Project Details
Project type
Exploratory Research
Start Date
2009-10-13
End Date
2010-10-17
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Qafoku O, JZ Hu, NJ Hess, MY Hu, ES Ilton, J Feng, BW Arey, and AR Felmy. 2013. "Formation of Submicron Magnesite during Reaction of Natural Forsterite in H2O-Saturated Supercritical CO2." Geochimica et Cosmochimica Acta. doi:10.1016/j.gca.2013.09.024
Rustad JR, WH Casey, QZ Yin, EJ Bylaska, AR Felmy, SA Bogatko, VE Jackson, and DA Dixon. 2010. "Isotopic Fractionation of Mg2+(aq), Ca2+(aq), and Fe2+(aq) with Carbonate Minerals." Geochimica et Cosmochimica Acta 74(22):6301-6323.