重油中沥青质、胶质及芳香分间相互作用计算

Calculation on Interaction Between Asphaltene, Resin,and Aromatic Components in Heavy Oil

重质油中的沥青质、胶质及芳香分间易发生交互作用形成团簇,严重影响重质油的加工和利用效率。采用透射电子显微镜(TEM)和分子模拟技术研究重质油中沥青质-胶质、沥青质-芳香分、胶质-芳香分复合物的聚集形貌和相互作用变化,以此为重质油组分聚沉现象的研究及改性剂的开发提供一定的理论支持。TEM表明沥青质-芳香分具有明显的堆积现象。其次,在B3LYP/6-31G(d)水平上,通过分析沥青质-胶质、沥青质-芳香分、胶质-芳香分构型的弱相互作用可视化图、AIM拓扑结构、轨道相互作用贡献和静电势分布特征,发现组分间相互作用以范德华作用为主,环间位阻作用为辅,并未因杂原子(N、S)的存在而产生静电吸引作用。

The interaction between asphaltene,resin,and aromatic components in heavy oil is prone to form clusters,which seriously affects the processing and utilization efficiency of heavy oil.Transmission electron microscopy(TEM)and molecular simulation techniques were used to study the aggregation morphology and interaction changes in asphaltene-resin,asphaltene-aromaticand resin-aromatic composites,providing theoretical support for the study of heavy oil component aggregation and the development of modifiers.TEM showed that there was a significant accumulation phenomenon of asphaltene-aromatic.Secondly,at the B3LYP/6-31G(d)level,by analyzing the visualization of weak interactions,AIM topology,orbital interaction contributionand electrostatic potential distribution characteristics of asphaltene-resin,asphaltene-aromatics,and resin-aromatics configurations,it was found that the interactions between components were mainly Van der Waals interactions,supplemented by inter ring steric hindrance,and no electrostatic attraction due to the presence of heteroatoms(N,S).