Coal Vitrinite Pyrolysis Studied by EPR

Abstract

Abstract:

Understanding coal combustion and spontaneous combustion are important for coal mine safety and high efficient utilization of coal resources. In this work, the free radical reactions of pyrolysed vitrinite under aerobic conditions were investigated. Vitrinite sample at normal temperature and heatdecomposition products of vitrinite between 300 ℃ to 450 ℃ under aerobic condition were investigated by electron paramagnetic resonance (EPR). The EPR′s signals of the heat-decomposition products produced at 300 ℃, 350 ℃, 400 ℃ and 450 ℃ were collected at 25 ℃. Heating temperature-related changes in EPR signals were analyzed. It was found that the composition and concentration of paramagnetic centers changed with heating temperature, probably originated from that fact that different free radicals were produced from different organic components at different heating temperatures.

Key words: electron paramagnetic resonance, coal, vitrinite, maceral, free radical

CLC Number:

O482.53

Yin Chun-Hao, ZHAO Qiang, TENG Dao-Xiang, LI Fu-Qiang, SHEN Gan, ZHU Shan-Shan. Coal Vitrinite Pyrolysis Studied by EPR[J]. Chinese Journal of Magnetic Resonance, 2011, 28(4): 464-470.

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