Comment on ‘Investigating CO₂ sequestration via enhanced rock weathering: Effects of temperature and citric acid on dolomite and basalt’

Xu et al. (2024) reported a carefully conducted soil incubation study into CO2 capture following application of crushed dolomite or basalt, but we have re-examined their data and arrived at different conclusions. While Xu et al. collected sufficient C data to measure CO2 capture directly, they instead estimated it from the Mg balance and the assumption that release of Mg from the applied rock was associated with carbonic acid weathering. Although cation-based approaches have been used widely in the past, they do not provide an accurate estimate of CO2 capture in most situations (Green et al., 2024; Hasemer et al., 2024). We show here that when CO2 capture was calculated directly from the C balance, the effects of the treatments on CO2 capture differed from the original published estimates; dolomite addition led to CO2 capture, but basalt addition did not.

Journal of Cleaner Production

Journal of Cleaner Production

533

0959-6526

N/A

N/A

2