先锋褐煤在高压釜中用等体积的甲醇/甲苯溶剂300℃下热溶得到热溶物和热溶残渣,利用X射线光电子能谱(XPS)分析了先锋褐煤及其热溶残渣中氮的形态,利用气相色谱/质谱(GC/MS)和电喷雾傅里叶变换-离子回旋共振质谱(ESI FT-ICR MS)分析了热溶物中含氮化合物的组成和结构特征.研究表明,先锋褐煤中氮形态含量顺序为季氮>吡啶氮>吡咯氮,而季氮在热溶过程中更易溶出.GC/MS共检测出热溶物中20种含氮化合物,并且大部分为胺类化合物.ESI FT-ICR MS检测出热溶物中300多种含氮化合物,大部分含氮化合物含一个或三个氮原子.含一个氮原子的含氮化合物主要以N1O1、N1O2和N1OxS1-2类化合物为主,而含三个氮原子的含氮化合物主要以N3OxS1-2(x=1-12)类化合物为主.含一个氮原子的含氮化合物的等效双键数和碳数随氧原子数增加而增加.%Xianfeng lignite ( XL ) was firstly thermal dissolved in the isometric toluene/methanol mixed solvent at 300 ℃ in a stainless-steel autoclave to afford a soluble portion ( SPXL ) and a residue ( RXL ) , then the nitrogen forms in XL and RXL were characterized with X-ray photoelectron spectroscopy ( XPS) analysis, and the nitrogen-containing species ( NCSs) in SPXL were identified using gas chromatography/mass spectrometry ( GC/MS) and electrospray ionization Fourier transform ion cyclotron mass spectrometry ( ESI FT-ICR MS) analyses. The results show that the amount of nitrogen forms in XL is in the order of quaternary-N>pyridinic-N>pyrrolic-N, while quaternary-N in XL is easily dissolved out during thermal dissolution. In total 20 NCSs were detected in SPXL by GC/MS, and most of them are amines. Over three hundreds of NCSs were identified in SPXL by ESI FT-ICR MS, and most of them are the NCSs containing one or three nitrogen atoms. The NCSs containing one nitrogen atom are mainly dominated by N1 O1 , N1 O2 and N1 Ox S1-2 class species, while most of NCSs containing three nitrogen atoms are N3 Ox S1-2 class species ( x=1-12 ) . The double bond equivalent ( DBE ) values and carbon number of the NCSs containing one nitrogen atom increase with increasing number of oxygen atoms.
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