减压渣油的胶体结构及其形成

应用冷冻断裂复形透射电子显微镜法研究了三种典型国产减压渣油的物理结构。结果表明，减压渣油是溶胶态胶体分散体系，正庚烷沥青质和胶质重组分构成分散相胶团。胶质以两种状态存在：胶质重组分缔合形成分散相胶团，其余的胶质组分与油分（芳香分＋饱和分）一起构成分散介质。分析了三种减压渣油及其组分的红外光谱、化学组成与结构参数，考察了渣油胶体结构的形成机制。研究发现，高电负性杂原子和芳香性是形成胶团的充分必要条件，氢键是形成胶团的重要分子相互作用方式。胶团的多少和聚集状态取决于正庚烷沥青质和胶质重组分的多少，以及它们的高电负性杂原子含量和芳香性的高低。

COLLOIDAL STRUCTURES AND THEIR FORMATION IN PETROLEUM VACUUM RESIDUA

The freeze fracture replication electronic transmission microscopy was adopted to investigate the physical structures of three typical Chinese petroleum vacuum residua. It was discovered that the vacuum residua assume the sol like colloidal dispersion, in which the asphaltenes(the n heptane-insoluble and toluene soluble fraction) and the heavier resin fraction with higher polarity and molecular weight constitute the dispersed micelle. There exist two physical states for the resin fraction: the heavier sub fraction with higher polarity co aggregates to form the micelle and the remaining sub fraction constructing the dispersing media together with the oils(aromatics and saturates). Meanwhile, some light was thrown upon the predominant interaction modes responsible for the formation of the colloidal structures of the three vacuum residua through the scrutiny of the infra red spectra, compositional and structural parameters of the three vacuum residua and their SARA fractions. The heteroatoms(S, N, O) with high eletronegativity and the large molecular structure with high aromaticity are the sufficient and necessary pre requisites for the micelle formation. The hydrogen bonding is the fundamental mode for the construction of the micelle, and the quantity and physical state of the micelle in vacuum residua depend heavily on the concentrations of the asphaltenes and the heavier resins with high polarity, aromaticity as well as the contents of heteroatoms in these molecules.