@misc{10481/107590,
year = {2025},
month = {9},
url = {https://hdl.handle.net/10481/107590},
abstract = {Portland cement largely replaced hydraulic lime over the past century
because of its rapid hardening. Achieving earlier hardening in lime through faster
carbonation is thus essential to help overcome one of lime’s limiting qualities. Here,
we isolated two alkaliphilic bacteria, Shouchella clausii and Shouchella patagoniensis,
from a lime mortar wall. S. clausii was then further grown in high pH (>11) by adaptive
laboratory evolution to acclimate a third isolate. Bacterial suspensions of all three isolates
were followed for 14 days in serum bottles at pH 11, and gas composition of the
headspace, intact/damaged cell populations, and pH were measured. In parallel, lime
mortar samples were incubated in a closed environment with bacterial suspension of the
isolates and analyzed with thermogravimetric analysis after 7 and 14 days to quantify
carbonation. S. patagoniensis produced more CO2, close to the estimated maximum
CO2 uptake rate of lime, and carbonated the lime mortars to a larger extent than
the other isolates. Finally, the bacterial suspensions were directly mixed with lime. A
linear and homogeneous carbonation of the paste samples was measured compared to
water-based pastes, and the development of Liesegang patterns was observed upon
phenolphthalein spreading. All this indicated that the organic addition altered the
carbonation dynamics of the material, although bacteria did not accelerate carbonation
relative to media alone and inhibited it relative to water-based paste. Still, a relationship
between bacterial activity, CO2 emission, and carbonation rate was established, but
practical aspects of bacterial delivery into lime must be addressed.},
organization = {European Union’s Horizon 2020 - Marie Sklodowska-Curie (project SUBLime, grant agreement no. 955986)},
publisher = {American Society for Microbiology},
keywords = {Carbonation},
keywords = {lime-based},
keywords = {Mortar},
title = {Characterization of isolates used in bacterial-based strategies for accelerated carbonation of lime mortars},
doi = {10.1128/aem.00683-25},
author = {Grosso Giordano, Franco and Mariën, Quinten and De Belie, Nele and Rodriguez-Navarro, Carlos and Boon, Nico},
}