【摘要】 为了提高热解煤焦油中自由基含量的检测精度,了解其样品最佳保存温度与其自由基含量变化的原因,对不同保存温度和不同时间下的焦油样品进行了EPR测试,利用标准曲线法对焦油中的自由基进行定量;同时对不同保存时间的焦油样品进行了1H-NMR测试,进行质子化学位移归属,计算不同化学位移段的积分面积百分比。结果表明:保存温度越高,焦油中自由基含量增加趋势越明显;能够保持热解煤焦油中自由基含量不变的最高温度约为-40℃以下。1H-NMR结果显示,导致热解煤焦油中自由基含量增加的原因可能是焦油中结构单元之间的桥键断裂生成新的自由基所致。为测定焦油中自由基含量时的保存条件提供了理论依据。更多还原

【Abstract】 The stability of free radicals in tars is relatively poor in the research of low bank coal pyrolysis tars using EPR spectroscopy,which is bad for measurement.To investigate the best preserving temperature of tars and the changing reason of free radicals,,EPR and 1H-NMR analyses of different preserving temperatures and retention time tars were conducted.The results showed that free radicals concentration is being increased with the increasing of temperature;and the highest preserving temperature to keep the free radicals concentration invariant may be below –40℃.The 1H-NMR analysis shows that the heteroatomic bond breaking may cause the increase of free radicals.更多还原