借助傅里叶变换红外光谱仪对伊敏褐煤不同化学组分的结构特征进行了分析,并运用origin7.5软件对伊敏褐煤不同化学组分红外光谱曲线进行了分段分峰拟合,计算了伊敏褐煤不同化学组分的红外光谱结构参数。结果表明,脱灰后伊敏煤的羧基振动强度增强,由原煤中的肩峰变为尖峰,脂肪CH和芳香CH的振动也均受到影响,表现为,苯环四取代增多,苯环二取代减少,脂肪CH2振动减少,脂肪CH3振动增加,结构参数I1,I2和A值均增大,表明其具有良好的潜在生烃能力;腐殖酸和沥青质中的羧酸及OH-π氢键含量较高,芳香结构中苯环四取代和苯环一取代较多,脂肪CH振动所占比例较高,而不对称CH2振动所占比例较低,红外光谱结构参数的计算结果显示腐殖酸的脂肪氢浓度最大,说明腐殖酸和沥青质中含有的脂肪烃其长度较短,且支链化程度较高;残煤中的芳香C=C振动较大,脂肪烃以长链为主,且支链较短。

Structural characteristics of different chemical components of Yimin lignite were analyzed by using Fourier transform infrared spectroscopy (FTIR),the curve-fitting analysis was employed to characterize the infrared spectrum different chemical components of Yimin lignite by using origin 7. 5 software,and the FTIR structure parameters were also calculated. The results were obtained as following:for the demineralized coal,comparing with the raw coal,the car- boxyl vibration peak became sharp,two adjacent hydrogen increased and four adjacent hydrogen decreased,aliphatic CH2 vibration decreased and aliphatic CH3 vibration increased,FTIR structural parameters I1 ,I2 and A all increased, which demonstrated its good hydrocarbon generation capacity;for humic acid and asphaltene,they have more carboxyl- ic acid and OH-π hydrogen bond,more two adjacent hydrogen and five adjacent hydrogen,more aliphatic CH vibra- tion and less CH2 vibration,the humic acid has the most aliphatic hydrogen,indicating that the aliphatic hydrocarbons in humic acid and asphaltene is short and high branched;for the residue,it has more aromatic C C vibration,and the aliphatic chain is long and less branched.