山西晋城地区含煤地层中的铵伊利石/蒙脱石间层矿物

Ammonium-illite smectite interlayer clay minerals in coal-bearing strata in Jincheng district of Shanxi Province

运用X射线衍射分析、傅里叶红外光谱分析以及热重-热流-红外光谱同步分析等手段,对山西晋城地区的9号煤层夹矸及底板进行了矿物学研究,发现夹矸和底板中主要黏土矿物为铵伊利石/蒙脱石间层、伊/蒙间层、高岭石和钠云母,含有少量的伊利石。铵伊利石/蒙脱石间层矿物EG片X射线衍射图谱中1.033 nm(铵伊利石的d(001))左侧的子峰明显高于右侧的子峰,NH4+变形振动引起的红外特征吸收峰(位于1 427.09～1 433.34 cm-1)以及在加热到561℃左右会有大量NH3产生均是区分于其它黏土矿物的重要标志。铵伊利石/蒙脱石间层属于热液蚀变黏土矿物,是在有机质成熟度较高条件下,有机氮以NH4+释放出来并替代K+参与伊蒙间层矿物的伊利石化作用而成,形成温度在350℃左右。

X ray diffraction, fourier infrared spectrum and TGA-DSC combined with fourier infrared spectrum were used to study the mineralogical characteristics of the partings and floors of No. 9 coal in the areas of Jincheng in Shanxi Province. There are several important characteristics of ammoniumillite smectite interlayer including the sub-peak on the left of 1. 033 nm （d（001） of ammonium illite）higher than the right sub-peak, the IR absorption peaks from the distor- tion vibrtation of NH4 between 1 427.09 and 1 433.34 cm-1 and NH3 generated heated at the temperature of 561 ℃. Ammonium-illite smectite interlayer is hydrothermal altered clay minerals, generated from the illitization of illite smec- tite interlayers when K＋ is substituted by NH4＋ transformed from organic nitrogen in the condition of relatively high ma ture,and its formation temperature is about 350 ℃.