Infrared Spectrum Studies of Hydrocarbon Generation and Structure Evolution of Peat Samples During Pyrolysis and Microbial Degradation
BAO Yuan1, 2, JU Yi-wen1, WEI Chong-tao2, WANG Chao-yong2, LI Xiao-shi1
1. Key Laboratory of Computational Geodynamics of Chinese Academy of Sciences, College of Earth Science, University of Chinese Academy of Sciences, Beijing100049, China 2. Key Laboratory of CBM Resource and Reservoir Formation Process, Ministry of Education, School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221008, China
Abstract：Hydrocarbon generation and structural evolution would be occurred in the processof from coal-forming material (i.e. peat sample) transforming to the coal. While Fourier Transform Infrared Spectroscopy (FTIR) have a special advantages in analyzing molecular structure of samples. For understanding the characteristics of hydrocarbon generation and structural evolution of coal-forming material during the process of pyrolysis and microbial degradation, based on the physicalsimulation experiments of closed pyrolysis and anaerobic microbial degradation,the generation potential of thermogenic gas and biogenic gas were studied in this paper, and characteristics of molecular structure evolution and its mechanismwas analyzed by FTIR technology. Results show that cumulative gas yields ofhydrocarbon gases (mainly for methane) increased with experiment temperature. The gas yield of non-hydrocarbon gas (mainly for CO2) exhibited two peaks at 250 and 375 ℃. The degradation ability of anaerobe on coal samples weakened with the maturity increasing and there was no gas generation on the pyrolysis samples with maturity from 1.6% to 1.8%. After pyrolysis, the content of hydroxylin peat sample decreased first and then increased with the pyrolysis temperature increasing. The content of aldehyde carbonyl, methylene and phosphate reduced. The content of aromatic esters decreased with nonlinear. The bone of S-O instretching vibration appeared after 350 oC and its content increased with temperature. This shows that the sulfocompound restrains the activity of methanogenic bacteria. After degradation by anaerobe, the relative content of hydroxyl, aldehyde carbonyl, aromatic esters, methylene and phosphate in peat sample droppedsignificantly. It is shown that the intermolecular force between these groups weakened.
鲍 园1, 2，琚宜文1，韦重韬2，王超勇2，李小诗1 . 热解和生物降解对木本泥炭生烃与结构演化的红外光谱响应 [J]. 光谱学与光谱分析, 2015, 35(03): 603-608.
BAO Yuan1, 2, JU Yi-wen1, WEI Chong-tao2, WANG Chao-yong2, LI Xiao-shi1 . Infrared Spectrum Studies of Hydrocarbon Generation and Structure Evolution of Peat Samples During Pyrolysis and Microbial Degradation. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2015, 35(03): 603-608.
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