O-烷基化对煤中氢键的调控及对热解特性的影响

采用O－烷基化的方法对霍林河褐煤进行预处理，用原位漫反射红外光谱结合热重研究了处理前后煤中氢键的变化规律及热解特性。提出采用煤中高岭土、伊利石等在3690cm－1附近的红外吸收峰作为标准，校正煤的漫反射红外谱图的方法。结果表明，采用O-烷基化方法处理霍林河原煤后，其中的氢键数量有明显的减少，但均不能完全消除煤中的氢键；对于各种氢键调控幅度的大小随氢键强度的增大而逐渐减少；调控后煤中的氢键在高温区的热解稳定性增加；经O-烷基化后，煤的热解转化率增加，初始温度降低，热解温区加宽，失重速率加快。

REGULATION OF HYDROGEN BONDS IN COAL THROUGH O-METHYLATION AND ITS EFFECT ON PYROLYSIS PROPERTY

The variation and thermal stability of hydrogen bonds (HBS) in Huolinhe lignite before and after O-methylation treatment were studied by in-situ diffuse reflectance FTIR(DRIFT). The pyrolysis behavior of the raw and treated coal was investigated by TG. A new calibration method using the band of kaolinite and illite near 3690cm－1 as the basis was suggested to compare the spectrum of the raw and treated coal. The results show that the amount of HBS greatly decreased after O-methylation, but it could not be eliminated completely. The decrease extent of HBS depends on the kinds of HBS. The weaker the HBS are the less the regulation extent will be. The thermal stability of HBS in coal after O-methylation increased at high temperature. During pyrolysis the O-methylated coal has greater conversion, lower initial decomposition temperature, wider pyrolysis temperature range and higher weight loss rate than the raw coal.