skip to main content


Title: Conductivity measurements on H 2O-bearing CO 2-rich fluids

Recent studies report rapid corrosion of metals and carbonation of minerals in contact with carbon dioxide containing trace amounts of dissolved water. One explanation for this behavior is that addition of small amounts of H 2O to CO 2 leads to significant ionization within the fluid, thus promoting reactions at the fluid-solid interface analogous to corrosion associated with aqueous fluids. The extent of ionization in the bulk CO 2 fluid was determined using a flow-through conductivity cell capable of detecting very low conductivities. Experiments were conducted from 298 to 473 K and 7.39 to 20 MPa with H 2O concentrations up to ~1600 ppmw (xH 2O ≈ 3.9 x 10 -3), corresponding to the H 2O solubility limit in liquid CO 2 at ambient temperature. All solutions showed conductivities <10 nS/cm, indicating that the solutions were essentially ion-free. Furthermore, this observation suggests that the observed corrosion and carbonation reactions are not the result of ionization in CO 2-rich bulk phase, but does not preclude ionization in the fluid at the fluid-solid interface.
 [1] ; ;  [1] ;  [1]
  1. Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Solution Chemistry
Additional Journal Information:
Journal Volume: 44; Journal Issue: 5; Journal ID: ISSN 0095-9782
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; CO2 + H2O; carbonic acid; ionization; conductivity; carbon sequestration; CCS; EGS; electrolytic conductivity
OSTI Identifier: