Biodegradation of photo-oxidized lignite and characterization of the products

2017 3rd International Conference on Environmental Science and Material Application

生态环境科学;材料科学

Li, Jiantao^1,2 ; Liu, Xiangrong^1 ; Yue, Zilin^1 ; Zhang, Yaowen^1

College of Chemistry and Chemical Engineering, Xi'An University of Science and Technology, Xi'an

710054, China^1

College of Chemical Engineering and Modern Materials, Shangluo University, Shangluo, Shaanxi

726000, China^2

关键词: Degradation process;    Degradation products;    Gas chromatography-mass spectrometries (GC-MS);    Low-molecular-weight organic compounds;    Photo-oxidation pretreatment;    Physical morphology;    Pseudomonas aeruginosa;    Unsaturated structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/108/4/042122/pdf
DOI  :  10.1088/1755-1315/108/4/042122

来源: IOP

【 摘 要 】

Biodegradation of photo-oxidized Inner Mongolia lignite by pseudomonas aeruginosa was studied and the degradation percentage reached 56.27%, while the corresponding degradation percentage of the strain degrading raw Inner Mongolia lignite is only 23.16%. The degradation products were characterized. Proximate and ultimate analyses show that the higher oxygen content increased by photo-oxidation pretreatment maybe promoted the degradation process. Ultraviolet spectroscopy (UV) analysis of the liquid product reveals that it contains unsaturated structures and aromatic rings are the main structure units. Gas chromatography-mass spectrometry (GC-MS) analysis indicates that the main components of the ethyl acetate extracts are low molecular weight organic compounds, such as ketones, acids, hydrocarbons, esters and alcohols. Infrared spectroscopy (IR) analysis of raw lignite, photo-oxidized lignite and residual lignite demonstrates that the absorption peaks of functional groups in residual lignite disappeared or weakened obviously. Scanning electron microscopy (SEM) analysis manifests that small holes appear in photo-oxidized lignite surface, which may be promote the degradation process and this is only from the physical morphology aspects, so it can be inferred from the tests and analyses results that the more important reason of the high degradation percentage is mostly that the photo-oxidation pretreatment changes the chemical structures of lignite.