Unraveling the kinetics, mass transfer, and multi-omics for environmentally sustainable CO2 bio-mitigation using Bacillus cereus for bioenergy feedstock production

Abstract

This research provides a cost-competitive solution to the conflict between ever-increasing energy demand and hazardous carbon dioxide (CO2) emissions reduction from the industries. The paper outlines the use of chemolithotrophic bacteria (B. cereus SSLMC2) for the bio-mitigation of 10, 15, 20, and 25 % CO2 conducted using a 20 L bubble column bioreactor. For 10, 15, 20, and 25 % CO2 (g), the maximum biomass productivity achieved was 0.042, 0.035, 0.032, and 0.051 g L−1 h−1, respectively. The highest percentages of CO2 (g) removal achieved were 91.68, 86.83, 84.86, and 93.43 %, respectively. The effect of parameters on biomass growth and total carbon (C) assimilation was investigated to determine the correlation between the mitigation of CO2 (g) and the growth of B. cereus SSLMC2. The gas chromatography-mass spectrometry (GC-MS) examination of biomass confirmed the formation of potential products during the bio-mitigation process. The nuclear magnetic resonance (NMR) metabolomics technique identified up to 25 metabolites associated with probable bio-mitigating CO2 (g) pathways. Kinetic models such as Monod, Haldane, Powell, Webb, and Luong provided a mathematical depiction of bacterial growth dynamics. Additionally, the mass and heat transfer characteristics crucial to the bio-mitigation process were determined. By demonstrating high CO2 removal efficiencies and the production of valuable by-products, this research highlights the potential of integrating bio-based technologies into existing industrial processes.