Biological Modification of Montan Resin from Lignite by Bacillus benzoevorans

The montan resin (MR) is a solid waste produced during the industrial process of refined montan wax from lignite, and usually disposed by landfill and incineration, which easily cause environmental pollution and resource waste. Based its physicochemical properties, our study attempted to modify MR by Bacillus benzoevorans to achieve ecological utilization of MR. As results, the weight loss rate of MR, expressed as modification degree, was found to increase with the increase of B. benzoevorans-incubated time. The apparent oil-water partition coefficient (Kow), used to evaluate the improvement on hydrophilicity of MR, significantly increased (P < 0.01) after modification. IR analysis showed the functional groups of -OH and C=O in modified MR were more than those in MR. Meanwhile, comparison of the chemical changes between MR and modified MR by relatively quantitative analysis of gas chromatography-mass spectrometry (GC-MS) revealed that the content of some chemical components in the latter decreased, and the newly appeared chemical components all had more oxygen-containing functional groups. The bioactivity of the modified MR in agricultural application was evaluated regarding germination and seedling growth of maize seed preliminarly. Compared with the original MR-treated group, the modified MR showed an obvious effect on promoting the growth and germination of maize.