Quantitative Review of Olivine Carbonation Kinetics: Reactivity Trends, Mechanistic Insights, and Research Frontiers

Abstract

Magnesium-dominant olivine (Mg2SiO4) has received considerable attention for geologic and ex situ carbon mineralization due to its reaction potential with CO2 and its abundance in mafic and ultramafic rocks. To enable better predictions and optimization of its carbonation rate, here we compile the results of 15 separate studies into an internally consistent kinetic framework. Time-dependent transformation curves were determined, analyzed, and used to calculate temperature-dependent carbonation rate constants between 50 and 300 °C. The unified results clearly show that olivine carbonation is optimized at 185–200 °C and indicate a change in the carbonation reaction mechanism above 90 °C. Additional outcomes include the identification of important knowledge gaps and research frontiers for carbon mineralization, including those related to unraveling competitive serpentinization reactions, H2O-saturated supercritical CO2 (wet scCO2) reactivity, and the formation and impacts of secondary surface coatings. In addition to supporting the deployment of carbon storage technologies in a climate-responding world, the findings may help improve understanding of how carbonation and serpentinization processes influence critical geochemical cycles.

Synthetic Fluid Inclusions XXIV. In situ Monitoring of the Carbonation of Olivine Under Conditions Relevant to Carbon Capture and Storage Using Synthetic Fluid Inclusion Micro-Reactors: Determination of Reaction Rates

“…Because olivine is a rock forming mineral in both basalts and peridotites, the olivine carbonation reaction has been studied over a wide range of pressures, temperatures, and fluid compositions (PTX) using various experimental techniques (Giammar et al, 2005;O'Connor et al, 2005;Béarat et al, 2006;Chen et al, 2006;Gerdemann et al, 2007;Garcia et al, 2010;Kwak et al, 2010Kwak et al, , 2011Daval et al, 2011;Saldi et al, 2013;Gadikota et al, 2014;Johnson et al, 2014;Lafay et al, 2014;Sissmann et al, 2014;Eikeland et al, 2015;Turri et al, 2017;Ueda et al, 2017;Prikryl et al, 2018;Miller et al, 2019b). In this study, we present experimentally determined rates of olivine carbonation at temperatures ranging from 50 to 200 • C in the presence of an aqueous solution with salinity similar to that of seawater, using synthetic fluid inclusions (SFI) as micro-reactors.…”

Room temperature facile synthesis of olivine-Co2SiO4 nanoparticles utilizing a mechanochemical method

“…The Fe-and Mg-end-members of the naturally occurring (Fe 1Àx Mg x ) 2 SiO 4 solid solution have been the subject of intensive studies in mineralogy, as refractories, lithium battery materials, and for carbon sequestration. [1][2][3] Mg 2 SiO 4 occurs in three well-known equilibrium polymorphs, referred to as a (forsterite, orthorhombic Pnma olivine structure), b (wadsleyite, orthorhombic Imma spinelloid structure), and g (ringwoodite, cubic spinel structure) phases. The latter two of these polymorphs (b and g) are stable at elevated pressure and temperature conditions, yet both can be metastably quenched.…”

Kinetics and Mechanisms of ZnO to ZIF‐8 Transformations in Supercritical CO2Revealed by In Situ X‐ray Diffraction

“…In particular, nucleation of ZIF‐8 occurs on the ZnO surface rather than randomly and homogeneously over the entire untransformed portion of the material, as implied in the Avrami model. This model, however, is ideal for transformations with sigmoidal reaction profiles and has been successfully applied to solvothermal and hydrothermal fluid–solid reactions, including the formation of ZIFs . Indeed, reflecting on such observations can facilitate both a qualitative assessments of physical differences between reaction environments and intrinsic reaction mechanisms.…”

“…Second, analysis of the dimensionless Avrami exponent ( n ) can yield mechanistic information, although assigning specific physical significance to exponents remains problematic. Broadly, however, trends in n as a function of temperature, time, and reaction condition can provide some mechanistic insights . In the analysis of reported n values for ZIF‐8 precipitation, a variety of pathways have been proposed: from homogeneous nucleation of spherical shapes ( n ≈4), to processes that are rate‐limited by a surface reaction ( n ≈1) and diffusion ( n <1) .…”