高分辨质谱解析委内瑞拉奥里常渣减黏反应杂原子化合物组成变化

Heteroatomic compositional analysis of Venezuela Orinoco AR and the visbreaking product by negative ion ESI-FT-ICR MS

运用电喷雾-傅里叶变换离子回旋共振质谱仪（ESI-FT-ICRMS）,研究委内瑞拉奥里常渣减黏裂化反应前后杂原子组成及分布。常渣中O2类化合物的相对丰度最大,减黏裂化反应使O2、O1、N1O2、S1、O1S1、O2S1类化合物减少,甚至消失,而N1、N2、N2O1、N2S1、N3、N3O1、N1S2类化合物增多,减黏产物中N1类化合物的相对丰度最大。减黏前原料中等价双键加环数（DBE）为3和4的O2类化合物相对丰度较高,表明2、3元环环烷酸是委内瑞拉奥里常渣酸性化合物的主要成分,但反应使得O2类化合物相对丰度显著降低且碳数减小,主要是DBE为1~4的化合物。奥里常渣中N1类化合物相对丰度分布的质量重心在DBE为12处,减黏产物中N1存在两个质量重心DBE为12和DBE为15处,但是碳数分布范围及丰度较强的碳数均降低,表明N1类化合物主要发生侧链的裂化反应。

Molecular transformations of heteroatomic compounds during visbreaking of Venezuela Orinoco AR were studied by ultrahigh-resolution negative ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry（ESI-FT-ICR MS）.The results indicated that the relative abundance of O2,O1,N1O2,S1,O1S1 and O2S1 are decreased or even disappeared,but those of N1,N2,N2O1,N2S1,N3,N3O1,and N1S2 are increased after the visbreaking.The highest relative abundance is O2 class in Venezuela Orinoco AR,while in the visbreaking product（VB） it is N1.The high abundance O2 class contains the species with double bond equivalents（rings plus double bonds,named DBE） 3 and 4 in the AR,which are 2 or 3 cyclic naphthenic acids.By visbreaking,the relative abundance of O2 class is decreased and carbon number is also reduced,mainly DBE 1~4 compounds.The highest abundance N1 class contains the species with DBE 12 in the AR.After visbreaking,a bimodal DBE distribution around 12 and 15 is observed for the N1 class,suggesting two possible stable core structures.The distribution of carbon number and highly abundance of carbon number distribution is reduced,suggesting that the side-chain cracking reaction is mainly concerned for N1 class compounds.