芳烃类有机溶剂对羊场湾煤显微组分的超声辅助萃取

Ultrasonic Assisted Extraction of Macerals From Yangchangwan Coal by Aromatic Organic Solvents

选用宁夏宁东羊场湾(YCW)煤作为研究用煤,结合超声辅助萃取技术,考察了3种芳烃类有机溶剂(苯、甲苯、二甲苯)对2种煤岩显微组分(镜质组和惰质组)萃取结果的影响。结果表明:镜质组的萃取产率均高于惰质组。首先,通过傅里叶红外(FT-IR)研究发现,芳烃类溶剂可有效地分离出煤中的脂肪烃,且萃取产物中含有更多的长链脂肪烃结构。其次,萃取产物的气相色谱-质谱联用(GC-MS)结果显示,萃取产物主要由脂肪烃和酯类化合物组成,其中惰质组正构烷烃的相对分子质量大于镜质组,酯类化合物主要以邻苯二甲酸酯和邻苯二甲酸二酯的形式存在。最后,通过X射线光电子能谱(XPS)分析发现,相比于惰质组,镜质组中含有更多的脂肪烃类物质,使其具有更高的萃取产率。由于二甲苯和甲苯萃取产物中惰质组的酯类化合物含量高于镜质组,推测惰质组中的碳氧双键主要以酯基的形式存在。

Here,Yangchangwan(YCW)coal from Ningdong,Ningxia,was selected,together with ultrasonic assisted extraction technology,the effects of three aromatic organic solvents(benzene,toluene,xylene)on the extraction of two kinds of macerals(vitrinite and inertinite)were investigated.The results reveal that the extraction yield of vitrinite is higher than that of inertinite.Firstly,it is found by Fourier transformed infrared spectroscopy(FT-IR)study that aromatic solvents could effectively separate aliphatic hydrocarbons from coal,and the extraction products contain more long chain aliphatic hydrocarbons.Secondly,the results of gas chromatography mass spectrography(GC-MS)show that the extracted coal are mainly composed of aliphatic hydrocarbons and ester.The relative molecular mass of n-alkanes in inertinite is larger than that in vitrinite,and ester compounds are mainly in the form of phthalate and diphthalate.Finally,X-ray photoelectron spectroscopy(XPS)analysis show that the vitrinite contain more aliphatic hydrocarbons than the inertinite,which results in higher extraction yield.Since the content of ester compounds in xylene and toluene extracted coal is higher than that in vitrinite,it is speculated that the C=O in inertinite mainly exists in form of ester.