This work focuses on exploiting the naturally occurring microbial calcium carbonate precipitation
catalyzed by microbial consortia within lakes and oceans biogeochemistry for carbon dioxide removal
from atmosphere. In this work, Bacillus subtilis OQ119616 was used for carbon dioxide sequestration
in equi-molar concentrations into Bacillus-induced calcium carbonate precipitation (BICCP). As this
process requires alkaline media, urea degradation by urease and nitrogen fixation were traced.
BICCP has been formed from calcium salts in the following order: chloride > nitrate > acetate > citrate.
However, conversion efficiency percentage (CE%) of calcium salts to CaCO3 exhibited a different
attitude of citrate > acetate > chloride > nitrate. Calcium citrate is excluded from consideration. Acetate,
however, is the most efficient salt; it significantly exhibited the highest CE%, with the least cost and
highest economic feasibility. The wide range in quantities, efficiency and feasibility indicates the
importance of the salt anion in BICCP. In addition, BICCP exhibited applicability in healing concrete
cracks, improving field capacity of sand soil and the subsequently improved seed germination of Vicia
faba. BICCP was also accompanied by adsorption of heavy metals as partial purging of waste/sewage
water for hygiene/reuse. Bacillus subtilis exhibited the ability to perform MICP, utilizing various calcium
salts in the following order: chloride > acetate > nitrate > citrate. However, acetate is the most efficient
salt of calcium to be converted to calcium carbonate precipitate by B. subtilis, as it exhibited the
highest conversion efficiency percentage (g/g %), with the least cost and highest economic feasibility.
Carbon dioxide removal (CDR) occurs at simultaneous equity to CaCO3 precipitation at mole/mole
ratios. Economic feasibility (US$/m3) showed that BICCP may be applicable in CDR for cleansing carbon
dioxide inside closed systems and for environmental safety. The bacterially induced CaCO3 proved
successful applicability in improving the field capacity of sand soil and growth of V. faba, healing
concrete cracks and sorption of heavy metals for depolluting sewage/wastewater for hygiene reuse.
BICCP could repair concrete cracks of 1–2 mm wide in 7 days by 210 * 106 cells/mL. Adsorption of heavy
metals (Pd, Zn, Cd and Cu) for partial removal of contaminants in/from waste/sewage water for hygiene
reuse.