Biodegradation of Aromatic Hydrocarbons Using ZnSe Nanoparticle-assisted Microbial System: Kinetic, GC–MS and Environmental Assessment
摘要
Aromatic hydrocarbons such as naphthalene and benzene are persistent environmental pollutants that pose significant ecological and health risks. In the present study, a synergistic system consisting of bacteria, Zinc-selenide nanoparticles (ZnSe), and biosurfactants was evaluated for the degradation of these hydrocarbons. Individual systems exhibited moderate degradation efficiencies, with bacteria showing 38% and 42% removal for naphthalene and benzene, respectively, while nanoparticles and biosurfactants contributed to partial degradation and enhanced substrate availability. In contrast, the combined bacterial-nanoparticle-biosurfactant system demonstrated significantly higher degradation efficiencies of 95% for naphthalene and 97% for benzene, indicating a strong synergistic interaction among the components. Kinetic analysis revealed that the degradation followed pseudo-first-order kinetics, with an increased rate constant in the combined system compared to the bacteria system alone. Thermodynamic parameters showed negative Gibbs free energy values (-0.37 and -0.32 kJ mol−1), positive entropy values (21.1 and 15.2 J mol−1 K−1) confirming the spontaneous and endothermic nature of the degradation process. GC–MS analysis identified intermediate metabolites formed during the transformation of hydrocarbons, enabling the proposal of possible degradation pathways. The enhanced performance of the combined system can be attributed to biosurfactant-mediated solubilization, nanoparticle-assisted catalytic interactions, and microbial metabolic degradation. The results demonstrated the potential of integrated biological-nanomaterial systems as an effective strategy for the remediation of hydrocarbon-contaminated environments.