Serpentinites and CO2 mineralogical sequestration

“Sequestration” (absorption) of atmospheric carbon dioxide in the soil, in the bottom of the ocean or in the rocks is one of the proposed approaches for the mitigation of climate change. In particular, some minerals can react with the CO2-rich rainwater, trapping CO2 itself in the rock itself.

 A recent study of the Institute of Geosciences and Earth Resources of CNR has analyzed the process in some outcrops of Tuscan ophiolitic rocks, highlighting the petrogenetic and geochemical evolution of serpentinites during their interaction with CO2-rich meteoric waters.

Based on analysis and field observations, the dissolution of pure brucite - an extremely reactive mineral at atmospheric conditions and observed in serpentinites - leads to the hydromagnesite formation with CO2 sequestration by three times higher than observed in the presence of Fe-rich brucite.

The study therefore allows to identify which are the minerals that lead to a highest efficiency of the CO2 sequestration, fundamental for the industrial application of the CO2 mineralogical sequestration.

Reference: Chiara Boschi, Andrea Dini, Ilaria Baneschi, Federica Bedini, Natale Perchiazzi, Andrea Cavallo. 'Brucite-driven CO2 uptake in serpentinized dunites (Ligurian Ophiolites, Montecastelli, Tuscany)'; Lithos, 288–289, 264–281, doi: doi.org/10.1016/j.lithos.2017.07.005.

CNR press release: www.cnr.it/it/news/7727/serpentiniti-e-sequestro-di-co2.

 

For further information please contact Chiara Boschi, CNR-IGG, chiara.boschi(at)cnr(dot)it.