Paper contribution

Biomineralization using Enzyme-induced carbonate precipitation under vacuum environment for bio-rocks formation on lunar surface

Yuru Chen; Gyeongjo Min; Daisuke Fukuda; Satoru Kawasaki

Proceedings
EUROCK 2026
Pages
921-927
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The utilization of lunar regolith as a construction material is a key strategy for in situ resource utilization (ISRU) in future lunar exploration. Enzyme-induced calcium carbonate precipitation (EICP) has been widely studied for soil improvement on Earth, but its performance under vacuum conditions remains unclear. In this study, soybean urease was used to investigate the feasibility of EICP under atmospheric and vacuum conditions. Urease activity, CaCO3 precipitation, and the morphology of the precipitation were systematically evaluated. The results show that soybean urease maintained effective catalytic activity under both conditions, and higher soybean concentration resulted in higher urease activity. In particular, the urease activity under vacuum conditions was generally higher than that under atmospheric conditions, indicating that reduced pressure can enhance urease-catalyzed urea hydrolysis. Ca²⁺ consumption occurred more rapidly under vacuum conditions, suggesting accelerated mineralization and more efficient CaCO3 precipitation. SEM observations revealed that CaCO3 crystals nucleated on particle surfaces and gradually developed into aggregated clusters, confirming that enzymatic mineralization and crystal growth can proceed effectively under vacuum conditions. These findings indicate that EICP under vacuum can generate sufficient mineral binders to produce bio-rocks from lunar regolith, offering a practical foundation for future lunar infrastructure and habitat construction.

Contributors

Authors

  1. Yuru Chen Hokkaido University, Japan ORCID 0000-0001-5443-5200
  2. Gyeongjo Min Hokkaido University, Japan
  3. Daisuke Fukuda Hokkaido University, Japan
  4. Satoru Kawasaki Hokkaido University, Japan

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References

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