Systematic degradation mechanism and pathways analysis of the immobilized bacteria: Permeability and biodegradation, kinetic and molecular simulation

In order to effectively improve the degradation rate of diesel, a systematic analysis of the degradation mechanism used by immobilized bacteria is necessary. In the present study, diesel degradation mechanisms were assessed by analyzing permeability, biodegradation, adsorption kinetics, and molecular simulation. We found that bacteria immobilized on cinnamon shells and peanut shells degraded relatively high amounts of diesel (69.94% and 64.41%, respectively). The primary degradation pathways used by immobilized bacteria included surface adsorption, internal uptake, and biodegradation. Surface adsorption was dominant in the early stage of degradation, whereas biodegradation was dominant in later stages. The diesel adsorption rate of the immobilized bacteria was in agreement with the pseudo second-order kinetic model. The immobilized bacteria and diesel interacted through hydrogen bonds. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of Chinese Society for Environmental Sciences, Harbin Institute of Technology, Chinese Research Academy of Environmental Sciences.