In situ molecular spectroscopic evidence for CO2 intercalation into montmorillonite in supercritical carbon dioxide.

The interaction of anhydrous supercritical CO(2) (scCO(2)) with both kaolinite and ~1W (i.e., close to but less than one layer of hydration) calcium-saturated montmorillonite was investigated under conditions relevant to geologic carbon sequestration (50 °C and 90 bar). The CO(2) molecular environment was probed in situ using a combination of three novel high-pressure techniques: X-ray diffraction, magic angle spinning nuclear magnetic resonance spectroscopy, and attenuated total reflection infrared spectroscopy. We report the first direct evidence that the expansion of montmorillonite under scCO(2) conditions is due to CO(2) migration into the interlayer. Intercalated CO(2) molecules are rotationally constrained and do not appear to react with waters to form bicarbonate or carbonic acid. In contrast, CO(2) does not intercalate into kaolinite. The findings show that predicting the seal integrity of caprock will have complex dependence on clay mineralogy and hydration state.

[1]  J. Kubicki,et al.  ATR-FTIR spectroscopic characterization of coexisting carbonate surface complexes on hematite , 2005 .

[2]  B. Lanson,et al.  Investigation of smectite hydration properties by modeling experimental X-ray diffraction patterns: Part I. Montmorillonite hydration properties , 2005 .

[3]  P. F. Martin,et al.  In situ XRD Study of Ca2+ Saturated Montmorillonite (STX-1) Exposed to Anhydrous and Wet Supercritical Carbon Dioxide , 2012 .

[4]  D. Bish,et al.  Baseline studies of the clay minerals society source clays: Powder X-ray diffraction analyses , 2001 .

[5]  B. Arey,et al.  Forsterite [Mg2SiO4)] carbonation in wet supercritical CO2: an in situ high-pressure X-ray diffraction study. , 2013, Environmental science & technology.

[6]  T. Plivelic,et al.  X-ray studies of carbon dioxide intercalation in Na-fluorohectorite clay at near-ambient conditions. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[7]  Jean-Michel Lemieux,et al.  Review: The potential impact of underground geological storage of carbon dioxide in deep saline aquifers on shallow groundwater resources , 2011 .

[8]  D. Hoyt,et al.  Metal Carbonation of Forsterite in Supercritical CO2 and H2O Using Solid State 29Si, 13C NMR Spectroscopy , 2010 .

[9]  D. Hoyt,et al.  High-pressure magic angle spinning nuclear magnetic resonance. , 2011, Journal of magnetic resonance.

[10]  H. Carr,et al.  The Principles of Nuclear Magnetism , 1961 .

[11]  B. C. Garrett,et al.  Infrared and Molecular Dynamics Study of D2O Rotational Relaxation in Supercritical CO2 and Xe , 1996 .

[12]  P. F. Martin,et al.  Brucite [Mg(OH2)] carbonation in wet supercritical CO2: An in situ high pressure X-ray diffraction study , 2011 .

[13]  Irina Gaus,et al.  Role and impact of CO2–rock interactions during CO2 storage in sedimentary rocks , 2010 .

[14]  Herbert T. Schaef,et al.  Water reactivity in the liquid and supercritical CO2 phase: Has half the story been neglected? , 2009 .

[15]  D. Pines,et al.  Real-Time Observation of Carbonic Acid Formation in Aqueous Solution , 2009, Science.

[16]  Nannan Yang,et al.  Molecular simulation of swelling and structure for Na-Wyoming montmorillonite in supercritical CO2 , 2011 .

[17]  Odeta Qafoku,et al.  In situ X-ray diffraction study of Na+ saturated montmorillonite exposed to variably wet super critical CO2. , 2012, Environmental science & technology.

[18]  Virginie Marry,et al.  Carbon Dioxide in Montmorillonite Clay Hydrates: Thermodynamics, Structure, and Transport from Molecular Simulation , 2010 .

[19]  Koichi Nishikida,et al.  Effective path length in attenuated total reflection spectroscopy. , 2008, Analytical chemistry.

[20]  Robert C. Reynolds,et al.  X-Ray Diffraction and the Identification and Analysis of Clay Minerals , 1989 .

[21]  E. Ilton,et al.  In situ infrared spectroscopic study of forsterite carbonation in wet supercritical CO2. , 2011, Environmental science & technology.

[22]  Á. F. Cano,et al.  Baseline studies of the clay minerals society source clays: Chemical analyses of major elements , 2001 .

[23]  L. Vlček,et al.  Supercritical fluid behavior at nanoscale interfaces: Implications for CO2 sequestration in geologic formations , 2010 .

[24]  A. Busch,et al.  Interaction of carbon dioxide with Na-exchanged montmorillonite at pressures to 640 bars: Implications for CO2 sequestration , 2012 .