Enhanced triclocarban remediation from groundwater using Pseudomonas fluorescens strain MC46 immobilized on agro-industrial waste-derived biochar: Optimization and kinetic analysis

Triclocarban (TCC) is a widely used antimicrobial agent and has been identified as a subsurface contaminant. This study demonstrates enhanced TCC remediation using biochar-immobilized cells. The influence of operating and environmental parameters (including initial TCC concentration, pH, cell loading, and co-carbon source concentration) on TCC removal was investigated using one-factor-at-a-time (OFAT) and response surface methodology (R5M) analyses to determine the TCC removal performance. Pseudomonas fluorescens strain MC46 (MC46) was selected and supported on biochar from carbonized residue of wood vinegar production. The OFAT and RSM of the operating and environmental parameters resulted in TCC removal efficiencies of between 30% and 83%. The initial TCC concentration (5-20 mg L-1) significantly affected the removal rate (0.06- 9.23 mg L-1 d(-1)). The self-substrate inhibition kinetics followed a modified Edwards model with Ki of 599.65 mg L-1. Compared to previous work, higher Ki (less inhibition) were observed in this study and was due to the integration of biodegradation by MC46 and adsorption on the biochar-immobilized MC46. The biochar-immobilized cell technology is an efficient, sustainable, and economical method for future contaminant removal.