Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-24T18:15:10.671Z Has data issue: false hasContentIssue false
  • English
  • Français

Kinetic and structural constraints during glauconite dissolution: implications for mineral disposal of CO2

Published online by Cambridge University Press:  05 July 2018

S. Fernandez-Bastero ,
C. Gil-Lozano ,
M. J. I. Briones  and
L. Gago-Duport
S. Fernandez-Bastero
Affiliation:
Dept. Geociencias Marinas, Universidad de Vigo, 36310 Vigo, Spain
C. Gil-Lozano
Affiliation:
Dept. Geociencias Marinas, Universidad de Vigo, 36310 Vigo, Spain
M. J. I. Briones*
Affiliation:
Dept. Ecología y Biología Animal, Universidad de Vigo, 36310 Vigo, Spain
L. Gago-Duport
Affiliation:
Dept. Geociencias Marinas, Universidad de Vigo, 36310 Vigo, Spain
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The kinetics of glauconite dissolution have been determined in the pH range 2—10 (T = 25°C) using flow-batch reactor experiments. Besides the kinetic characteristics, the structural and textural aspects which could influence its long-term reactivity have also been characterized by means of X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and BET surface area measurements. The results from these analyses showed that glauconite follows a dual dissolution pathway which is pH-dependent, being more stable at neutral or slightly alkaline pH values. Under acidic conditions, glauconite is slightly more soluble than other ubiquitous silicates present in the marine sediments. The dissolution mechanism is incongruent at very acid pH values and tends to be congruent for intermediate and neutral ones. In addition, the results from the structural analyses suggest that the dissolution is a two-step process: the first one involves the disorder of the octahedral and tetrahedral layers, probably following a turbostratic mechanism which is evident in the XRD spectra as selective broadening of several reflections. In the second step, the dissolution of the cations from interlayer positions takes place and leads to the formation of an amorphous residue which acts as a passivating layer and reduces the reactive surface considerably. The influence of these aspects on CO2 capture via carbonation reactions is discussed.

Type
Research Article
Information
Mineralogical Magazine , Volume 72 , Issue 1 , February 2008 , pp. 27 - 31
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Blum, A.E. and Stillings, L.L. (1995) Feldspar dissolution kinetics. Pp. 291–351 in: Chemical Weathering Rates of Silicate Mineral. (White, A.F. and Brantley, S.L., editors). Reviews in Mineralogy 31, Mineralogical Society of America, Washington, D.C. Google Scholar
Fernandez-Bastero, S., Garcia, T., Santos, A. and Gago-Duport, L. (2005) Geochemical potentiality of glauconitic shelf sediments for sequestering atmospheric CO2 of antropogenic origin. Ciencias Marinas, 31, 593–615.CrossRefGoogle Scholar
Guthrie, G.D., Carey, J.W., Bergfeld, D., Byler, D., Chipera, S., Ziock, H.J. and Lackner, K.S. (2001) Geochemical aspects of the carbonation of magnesium silicates in an aqueous medium. NETL Conference on Carbon Sequestration.Google Scholar
Malmstrom, M. and Banwart, S. (1997) Biotite dissolution at 25“C: the pH dependence of dissolution rate and stoichiometry. Geochimica et Cosmochimica Ada, 61, 2779–2799.Google Scholar
Santos, A., Toledo-Fernandez, J.A., Roberto Mendoza-Serna, R., Gago-Duport, L., de la Rosa-Fox, N., Pinero, M. and Esquivias, L. (2007) Chemically active silica aerogel-wollastonite composites for CO2fixation by carbonation reactions. Industrial and Engineering Chemical Research, 46, 103–107.CrossRefGoogle Scholar
Wu, J.C.S., Sheen, ID., Chen, S.Y. and Fan, Y.C. (2001) Feasibility of CO2 fixation via artificial rock weathering. Industrial and Engineering Chemical Research, 40, 3902–3905.CrossRefGoogle Scholar