减压渣油胶体稳定性的分子模拟  

Investigating the Colloidal Stability of Vacuum Residue by Molecular Simulation

作　　者：张文[1] 龙军[1] 任强[1] 王春璐[1] 侯焕娣[1] 董明[1] ZHANG Wen;LONG Jun;REN Qiang;WANG Chunlu;HOU Huandi;DONG Ming(Research Institute of Petroleum Processing,SINOPEC, Beijing 100083, China)

机构地区：[1]中国石化石油化工科学研究院,北京100083

出　　处：《石油学报（石油加工）》2020年第3期533-542,共10页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：中国石油化工股份有限公司重大科研项目(ZD 118002-3)资助。

摘　　要：分子结构特性决定分子间相互作用,进而决定其溶解性能。通过分子模拟研究减压渣油不同结构分子的分子间相互作用、互溶性及由此导致的渣油胶体稳定性。研究表明,芳环数目越多、烷基侧链越短的分子结构内聚能密度越大,溶解度参数越大。在渣油体系中,沥青质、重胶质分子聚集形成胶核,饱和烃、芳香烃、轻胶质分子形成连续相。胶质分子结构影响其胶溶性能,侧链长度适中的胶质分子,其与沥青质、芳香分互溶性好,胶溶性能优异;沥青质的聚集程度随胶质分子含量的增加而降低。芳香分、胶质分子的协同作用使沥青质、饱和烃分子稳定存在于同一体系中,因此渣油胶体稳定性取决于不同分子结构的连续性和配伍性。Intermolecular interactions are determined by molecular structural properties,which then determine their solubility properties.Intermolecular interactions,miscibility of model molecules and the resulting colloidal stability of vacuum residue were studied by molecular dynamics simulations.The results show that the more the number of aromatic rings and the shorter the alkyl side chain of the molecular structure,the greater the cohesive energy density and the solubility parameter.In the residue systems,asphaltenes and heavy resins aggregate form a core,and saturated hydrocarbons,aromatic hydrocarbons,and light colloidal molecules form a continuous phase.The molecular structures of resin affect theirs peptization performance.The resin molecules with moderate length side chain have good miscibility with both asphaltene and aromatic hydrocarbon molecules,and have excellent peptization properties.The degree of aggregation of asphaltenes decreases with the increase of concentration of the colloidal molecules.The reason for that asphaltene and saturated hydrocarbon molecules co-exist in the same system is the synergistic effect of aromatic hydrocarbons and resin molecules.Therefore,the colloidal stability of the residue depends on the continuity and compatibility of different molecular structures.

关 键 词：减压渣油 溶解度参数 分子间相互作用 胶体稳定性 分子模拟 

分 类 号：TE621[石油与天然气工程—油气加工工程]