红外发射光谱法原位研究褐煤的低温氧化过程

STUDY OF LIGNITE OXIDATION AT LOW TEMPERATURES BY FTIR EMISSION SPECTROSCOPY

用傅氏红外发射光谱法原位考察了褐煤的低温氧化过程，用峰拟合程序处理光谱数据，在定量的基础上讨论了煤中各主要官能团的变化规律。数据表明，氧化时，煤的芳核部分是稳定的，氧原子主要进攻脂肪族基团，通过生成过氧化物进入煤结构中，整个过程表现为含氧基团的增多和脂肪族基的减少。作为褐煤低温氧化的一个特征是芳烃ＣＨ含量的逐渐递增，这主要是由于它含有较多羧基，其中芳酸的部分羧基发生脱羧的结果。

Low temperature oxidation of lignite was studied by in situ Fourier transform infrared emission spectroscopy The results demonstrate that the reactions mainly occur at the aliphatic branched chains, especially the αCH 2 attached to aromatic rings or C=O, or OR groups, when lignite is oxidized at a low temperature Oxygen attacks these susceptible groups and enters the coal structure through the formation of peroxides and hydroperoxides So, the results of lignite oxidation are increase of oxygenated groups and the decrease of aliphatic groups The aromatic parts of lignite seems to be unaffected by oxidation The increase of aromatic C-H bonds further shows that aromatic rings are not destroyed or condensed in oxidation process The main reason for the increase of aromatic C-H bonds is the decarboxylation of some carboxylic groups in oxidated lignite