煤直接液化重油胶质和沥青质中杂原子化合物的分子表征

Molecular Level Characterization of Heteroatom Compounds in Resins and Asphaltenes From Direct Coal Liquefaction Heavy Oils

采用傅里叶变换离子回旋共振质谱(FT-ICR MS)研究沸点大于360℃的煤直接液化重油中胶质、沥青质的组成,通过在分子水平上对杂原子化合物进行表征分析胶质、沥青质中杂原子类型、碳数分布和等效双键(DBE)。结果表明,煤直接液化重油中胶质及沥青质中杂原子化合物的分子组成十分复杂,采用正离子电喷雾结合高分辨傅里叶变换离子回旋共振质谱鉴定出了N1、N1O1、N2、N2O2、N2S15类不同分子组成的碱性氮化物和S1、S22种含硫化合物;采用负离子电喷雾鉴定出了N1、N1O1、N1O2、N2、N2O1、N2O26类非碱性氮化物和O1、O2、O3、O4、O5、O6、O1S1、O2S1、O3S1、O4S110类含氧化合物,其中碱性氮化物相对丰度较高的是N1类化合物,含硫化合物相对丰度较高的是S1类化合物,非碱性氮化物相对丰度最高的是N1O2类化合物,含氧化合物相对丰度最高的是O2类化合物。根据各类化合物的DBE和碳数分布,获得了煤直接液化重油中胶质、沥青质分子组成的重要信息。碱性N1类化合物主要母核结构是吡啶和喹啉为中心官能团的化合物,非碱性N1类化合物主要母核结构是苯并咔唑,S1类化合物主要以高缩合、长侧链的稠环含硫芳烃为主,O2类化合物主要母核结构是菲二酚及蒽二酚。

The composition of resins and asphaltenes in coal direct liquefied heavy oils with boiling point over 360℃was studied by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS).Heteroatom compounds were characterized at molecular level by heteroatom type,carbon number and double bond equivalent(DBE).Experimental results showed that the molecular composition of heteroatoms in resins and asphaltenes was very complex.Positive ions electrospray combined with high resolution FT-ICR MS identified five kinds of basic nitrogen compounds such as N1,N1O1,N2,N2O2 and N2S1,two kinds of sulfur compounds such as S1 and S2.Negative ions electrospray combined with high resolution FT-ICR MS identified six kinds of non-basic nitrogen compounds such as N1,N1O1,N1O2,N2,N2O1 and N2O2,ten kinds of oxygen compounds such as O1,O2,O3,O4,O5,O6,O1S1,O2S1,O3S1 and O4S1.Among them,the highest relative abundance of basic nitrogen was N1 compounds,the higher relative abundance of sulfur compounds was S1 compounds,the highest relative abundance of oxygen compounds was O2 compounds;and the highest relative abundance of non-basic nitrogen was N1O2 compounds.According to the equivalent double bond number(DBE)and carbon number distribution of various compounds,important information on the molecular composition of resins and asphaltenes was acquired.The main core structure of basic N1 compounds was a compound with pyridine and quinoline as the central functional group.The main core structure of non-basic N1 compounds was benzoxazole.S1 compounds were mainly polycyclic sulfur-containing aromatic hydrocarbons with highly condensed and long side chains.The main core structure of O2 compounds was phenanthrenediol and anthradiol.