Simulation of the nucleation and growth of simple clay minerals in weathering processes: The NANOKIN code

Fritz, Bertrand; Clément, Alain; Amal, Y.; Noguera, Claudine

doi:10.1016/j.gca.2008.11.043

Cited by 38 publications

(32 citation statements)

References 77 publications

(79 reference statements)

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“…Our simulation of amorphous silica precipitation relies on the theoretical approach of nucleation, growth and/or dissolution of particles of fixed composition in aqueous solutions, that we have previously developed and which is embedded in the NANOKIN code [27][28][29] . It includes a full treatment of speciation processes in the aqueous solution according to published data base 31,32 , and a full account of nucleation and growth processes during the formation of new particles.…”

Section: Methodsmentioning

confidence: 99%

“…In the present computational approach, we demonstrate that use of the classical nucleation theory and of a size dependent growth law, as embedded in the NANOKIN code [27][28][29][30] , allows a quantitative description of precipitation occurring under largely different experimental conditions : pre-established initial supersaturation 4 , supersaturation reached by neutralization of a high-pH silica solution 9 or by fast cooling 10 . In particular, we are able to discard the hypothesis of an induction time as an explanation for the plateaus observed in the saturation curves in these experiments.…”

Section: Introductionmentioning

confidence: 99%

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Precipitation mechanism of amorphous silica nanoparticles: A simulation approach

Noguera

Fritz

Clément

2015

Journal of Colloid and Interface Science

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Hypothesis: Despite its importance in numerous industrial and natural processes, many unsolved questions remain regarding the mechanism of silica precipitation in aqueous solutions: order of the reaction, role of silica oligomers, existence of an induction time and characteristics of the particle population. This may be traced back, in past models, to the lack of account of the first stages of nucleation, size dependence of the growth law, and full particle population.Computational method: A microscopic description of the nucleation and growth of amorphous silica nanoparticles is achieved which reproduces a large set of experimental measurements, under various thermodynamic conditions. The time evolution of the solution supersaturation and of the precipitate characteristics is established.Findings : A growth law of order 6 allows reproducing experimental results, without being correlated to the presence of silica oligomers in the aqueous solution. The saturation plateaus are shown not to be due to an induction period. The characteristics of the particle population are more complex than assumed by simple precipitation models (Johnson-Mehl-Avrami-Kolmogorov or Chronomal models) and strongly depend on how supersaturation is reached. Such a microscopic approach thus proves to be well suited to elucidate the mechanism of nanoparticle formation in natural and industrial contexts.

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Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Precipitation mechanism of amorphous silica nanoparticles: A simulation approach

Noguera

Fritz

Clément

2015

Journal of Colloid and Interface Science

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“…In order to understand the secondary mineral precipitation, more thermodynamic and kinetic data are needed as well as a better understanding of the problems related to nucleation and growth of hydrated crystalline phases and/or mineral solid solutions (e.g. Fritz et al, 2009). Summarizing, changes in all these factors are able to shift the sequence and quantity of secondary minerals formed as well as the reaction progress dependence on time.…”

Section: Comparison With Natural and Experimental Data And Computatiomentioning

confidence: 99%

CO2–water–basalt interaction. Numerical simulation of low temperature CO2 sequestration into basalts

Gysi

Stefánsson

2011

Geochimica et Cosmochimica Acta

106

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“…Although theoretical approaches to model such processes exist (e.g. Steefel and Van Cappellen, 1990;Fritz et al, 2009), they have not been applied extensively due to a lack of relevant data for mineral-fluid interfacial free energies inter alia. However, it has been recognized that the interaction of cement pore fluids with rocks and other engineered barrier components may well develop through an Ostwald step type sequence of alteration (e.g.…”

Section: Kineticsmentioning

confidence: 99%

A review of analogues of alkaline alteration with regard to long-term barrier performance

Savage¹

2011

Mineral. mag.

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Cement and concrete will be used as fracture grouts, shotcrete, tunnel and borehole seals, and as matrices for waste encapsulation inter alia in geological repositories for radioactive wastes. Alteration of the host rock and/or swelling clay in waste package buffers and tunnel backfills by hyperalkaline solutions from cement/concrete may be deleterious to system performance through changes in the physicochemical properties of these barrier materials.Analogue systems (and timescales) relevant to the understanding of the alkaline disturbed zone include: industrial analogues, such as alkaline flooding of hydrocarbon reservoirs (up to 30 y), cementaggregate reactions (up to 100 y) and the Tournemire tunnel (up to 125 y); and natural analogues, including the hyperalkaline springs at Maqarin, Jordan (more than 100,000 y), saline, alkaline lakes (more than 1,000,000 y) and certain fracture fillings in granites (more than 1,000,000 y).These systems show that alkaline alteration can be observed for thousands of years over distance scales of hundreds of metres under extreme conditions of hydraulic gradients in fractured rocks (Maqarin), but may be limited to a few centimetres over tens to a hundred years in mudstone (Tournemire). Important reaction mechanisms for retardation of alkaline fluids include: fluid mixing (alkaline oil floods, Maqarin), ion exchange (alkaline oil floods, Tournemire) and kinetic mineral dissolution-precipitation reactions (all systems studied). Qualitative and quantitative kinetic data for mineral reactions are available from cement aggregate reactions and the Searles Lake analogue, respectively. Short-term alteration observed in cement-aggregates is characterized by calcium silicate hydrate (C-S-H) minerals and incipient zeolite formation, whereas evidence from the Tournemire tunnel shows the growth of K-feldspar after relatively short time intervals (tens to a hundred years). There is a tendency for alkaline alteration to result in porosity decreases, but locally, porosity may be enhanced (e.g. near-injection well interactions in alkaline oil floods, or at fracture margins at Maqarin, Jordan). Data from industrial and natural analogues may thus supply some key data for bridging time and space scales between laboratory and in situ experiments on one hand and the requirements for safety assessment on the other.

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Simulation of the nucleation and growth of simple clay minerals in weathering processes: The NANOKIN code

Cited by 38 publications

References 77 publications

Precipitation mechanism of amorphous silica nanoparticles: A simulation approach

Precipitation mechanism of amorphous silica nanoparticles: A simulation approach

CO2–water–basalt interaction. Numerical simulation of low temperature CO2 sequestration into basalts

A review of analogues of alkaline alteration with regard to long-term barrier performance

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