原油减压渣油馏分的油-水界面性质Ⅱ.大庆减渣馏分与伊朗轻质减渣馏分油-水界面张力的比较

采用超临界萃取分离方法，将大庆减压渣油及伊朗轻质减压渣油按相对分子质量分割为两个系列共33个馏分。考察了它们的化学组成和界面张力，比较了两个系列减渣馏分在不同条件下油-水界面张力的变化规律。结果表明，大庆减渣馏分较伊朗轻质减渣馏分的芳香共轭结构和极性基团含量少，界面活性低。油相芳烃含量对两个系列油-水界面张力的影响不同，对大庆中间馏分的油-水界面张力影响大，而对伊朗轻质减渣中间馏分的影响小。水相因素对两个系列油-水界面张力的影响相似。水相中可溶性盐对油-水界面张力影响小，沉淀性盐对油-水界面张力影响大，对伊朗轻质减渣馏分的影响更明显。pH值对中间馏分油-水界面张力影响大，而对轻、重馏分影响小。

OIL-WATER INTERFACIAL PROPERTIES OF VACUUM RESIDUE FRACTIONS FROM CRUDE OIL Ⅱ.Comparison of Oil-Water Interfacial Tension of Vacuum Residue Fractions from Daqing and Iranian Light Crude Oils

The vacuum residua from Daqing and Iranian light crude oils were separated, according to the mean relative molecular mass, into two series, totally 33 fractions by the Supercritical fluid extraction and fractional (SFEF) technology. Properties like relative molecular mass, sulfur and nitrogen content,H/C atomic ratio and the interfacial tension of oil-water phase for the fractions were investigated. The tendency of oil-water interfacial tension of the two series of fractions was compared. The content of aromatic structures, polar groups in Daqing series fractions was lower than that in Iranian light series, at the same time, the oil-water interfacial activity of Daqing series fractions was lower than that of Iranian light series fractions. The effects of the aromatic content of oil phase on the oil-water interfacial tension of the two series were different, the fractions in the middle of Daqing series are affected by oil phase much more than those of Iranian light series. The effects of the water phase on the oil-water interfacial tension of the two series were similar. The precipitating salts affected the oil-water interfacial tension much more than the soluble salts do, especially in the case of Iranian light series. The effect of pH on the oil-water interfacial tension of middle fractions was more obvious than that of light fractions or heavy fractionsof both series.