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bioRxiv · 10.1101/2021.09.18.460930

Microbial induced calcite precipitation can consolidate martian and lunar regolith simulants

Dikshit, R.·Gupta, N.·Dey, A.·Viswanathan, K.·Kumar, A.
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Abstract

We demonstrate that Microbial Induced Calcite Precipitation (MICP) can be utilized for creation of consolidates of Martian Simulant Soil (MSS) and Lunar Simulant Soil (LSS) in the form of a brick. A urease producer bacteria, Sporosarcina pasteurii, was used to induce the MICP process for the both simulant soils. An admixture of guar gum as an organic polymer and NiCl2, as bio-catalyst to enhance urease activity, was introduced to increase the compressive strength of the biologically grown bricks. A casting method was utilized for a slurry consisting of the appropriate simulant soil and microbe; the slurry over a few days consolidated in the form of a brick of the desired shape. In case of MSS, maximum strength of 3.3 MPa was obtained with 10mM NiCl2 and 1% guar gum supplementation whereas in case of LSS maximum strength of 5.65 MPa was obtained with 1% guar gum supplementation and 10mM NiCl2. MICP mediated consolidation of the simulant soil was confirmed with field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). Our work demonstrates a biological approach with an explicit casting method towards manufacturing of consolidated structures using extra-terrestrial regolith simulant; this is a promising route for in situ development of structural elements on the extra-terrestrial habitats.

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Dikshit, R., Gupta, N., Dey, A., Viswanathan, K., Kumar, A.. 2021-09-20. Microbial induced calcite precipitation can consolidate martian and lunar regolith simulants. https://doi.org/10.1101/2021.09.18.460930

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