@article{TEXTUAL,
      recid = {14518},
      author = {Zeyen, Nina and Wang, Baolin and Wilson, Sasha and Paulo,  Carlos and Stubbs, Amanda R. and Power, Ian M. and  Steele-MacInnis, Matthew and Lanzirotti, Antonio and  Newville, Matthew and Paterson, David J. and Hamilton,  Jessica L. and Jones, Thomas R. and Turvey, Connor C. and  Dipple, Gregory M. and Southam, Gordon},
      title = {Cation Exchange in Smectites as a New Approach to Mineral  Carbonation},
      journal = {Frontiers in Climate},
      address = {2022-06-23},
      number = {TEXTUAL},
      abstract = {Mineral carbonation of alkaline mine residues is a carbon  dioxide removal (CDR) strategy that can be employed by the  mining industry. Here, we describe the mineralogy and  reactivity of processed kimberlites and kimberlite ore from  Venetia (South Africa) and Gahcho Kué (Canada) diamond  mines, which are smectite-rich (2.3–44.1 wt.%). Whereas,  serpentines, olivines, hydrotalcites and brucite have been  traditionally used for mineral carbonation, little is known  about the reactivity of smectites to CO<sub>2</sub>. The  smectite from both mines is distributed as a fine-matrix  and is saponite,  $M_{m+}^{x/m}Mg_3(Al_xSi_{4−x})O_{10}(OH)_2·nH_2O$, where  the layer charge deficiency is balanced by labile, hydrated  interlayer cations $(M^{m+})$. A positive correlation  between cation exchange capacity and saponite content  indicates that smectite is the most reactive phase within  these ultramafic rocks and that it can be used as a source  of labile $Mg^{2+}$ and $Ca^{2+}$ for carbonation  reactions. Our work shows that smectites provide the fast  reactivity of kimberlite to $CO_2$ in the absence of the  highly reactive mineral brucite $[Mg(OH)_2]$. It opens up  the possibility of using other, previously inaccessible  rock types for mineral carbonation including tailings from  smectite-rich sediment-hosted metal deposits and oil sands  tailings. We present a decision tree for accelerated  mineral carbonation at mines based on this revised  understanding of mineralogical controls on carbonation  potential.},
      url = {http://knowledge.uchicago.edu/record/14518},
}