1. Experimental investigation of supercritical CO2 reactivity
Centre de Géosciences
Experimental investigation of supercritical CO2 reactivity
Olivier Regnault a, Vincent Lagneau a, Hubert Catalette b
a ENSMP-CIG 35 rue Saint Honoré, Fontainebleau Cedex –
b EdF R&D Département étude des matériaux, Site des Renardières Route de Sens, Ecuelles, Moret sur Loing Cedex
French-Serbian European Summer University 16 – 25 October 2006
Renewable Energy Sources and the Environment

2. sc-CO2 potential reactant
Context of the study
Cap-rock
Aquifer
silicate dissolution + carbonate precipitation
dissolved CO2 main reactant
sc-CO2 potential reactant
Pure sc-CO2
cross dissolution
scCO2/H2O
H2O/aqCO2 ?
CO2 Injection well

3. Experimental conditions
Pressure ≈ 160 bars
Temperature = 200°C
Duration = 45 days
X CO2
P (bar)
Anhydrous sc-CO2
H2O/CO2

4. Selection of minerals
Selected pure minerals consistent with the mineralogy
of a geological formation and the cements of the borehole seals :
Anorthite (Feldspar, CaAl2Si2O8)
Phlogopite (Mica)
Forsterite (Olivine, Mg2Si2O5)
Portlandite Ca(OH)2
Those minerals have been crushed to enhanced the reactive surface and provite fresh surfaces.

5. Schematic section of the experimental device
Experimental protocol
Schematic section of the experimental device
Autoclave
Injection pit
Titanium cell
Thermal compressor P T
sc-CO2
Powdered pure minerals

7. Anorthite behaviours with a H2O/CO2 fluid (I)
Figure of dissolution
and clay growth
Tridymite (SiO2)

8. Anorthite behaviours with a H2O/CO2 fluid (II)
Calcite (CaCO3)
Aragonite (CaCO3)

9. Anorthite behaviours with anhydrous CO2
before reaction
carbonate and clay growth
fibrous calcite

10. Conclusions and Prospect
An effective mineral reactivity exits and ought to be
considered for CO2 sequestration studies.
The strong reactivity of portlandite Ca(OH)2 suggests
potential reaction with cements structures arround the
borehole : possible decrease of the sealing properties.
A new experiment is actually carried out : quantify and
measure first the portlandite carbonation kinetics.