阶梯式循环冲击下煤中氢键红外光谱变化规律

煤结构中存在的大量氢键对其化学结构和性质具有重要影响。为了研究煤在冲击破坏过程中氢键的变化。设计落锤循环冲击系统，实现对煤样的循环定量冲击。利用红外光谱仪进行光谱分析。研究得出东庞1/3焦煤主要的氢键类型是free OH groups, OH…π, OH…OH, cyclic OH tetramers和OH…N以及它们随冲击破坏的变化规律。在冲击力的作用下，煤体分子间氢键吸收强度变化非常明显，自由羟基也在冲击作用下发生机械力化学反应。对红外光谱进行高斯函数拟合分峰，发现各类氢键吸收强度随着冲能量的增加而减小，但其趋势在放缓。统计两者关系，得到各类氢键的光谱吸收强度与冲击能量的拟合方程，两者符合幂函数关系。对比拟合方程的幂指数，得出氢键在受冲击破坏时发生变化的敏感性顺序：free OH groups>cyclic OH tetramers>OH…N>OH…π>OH…OH。

FTIR Study of Hydrogen Bonds in Coal under Drop Weight Impact Testing

There are many hydrogen bonds in coal, which affect the chemical structure and properties of coal. FTIR has been applied to the characterization study of the hydrogen bonds of Dongpang coals, which were under drop weight impact. There exists five kinds of hydrogen bonds in the coal: free OH groups, OH…π, OH…OH, cyclic OH tetramers and OH…N. Absorption strength of intermolecular hydrogen bonds markedly declined after impact. Free OH groups mechanical-power chemical reacted in drop weight impact testing. The infrared spectrum were curve-resolved into their component bands. The absorption strength of various hydrogen bonds decreased with the increase of impact energy, but the trend was slowing. By statistical relationship between then, we find then complying with power function relationship. By comparing the exponents of fitted equations, we concluded that failure sensitivity sequence of hydrogen bonds to the impact: free OH groups>cyclic OH tetramers>OH…N>OH…π>OH…OH.