质量分率电导率法研究几种不同渣油的胶体稳定性

测定了中东常压渣油、中东减压渣油、大庆减压渣油和中东减压渣油正庚烷可溶质在用正庚烷稀释过程中的电导率，并计算得到了不同正庚烷稀释比例时的质量分率电导率，将质量分率电导率出现最大值时的（正庚烷/渣油）比值定义为渣油胶体稳定参数。用该方法研究不同渣油的胶体稳定性，对以上几种油品的研究结果与各油品的饱和分、芳香分、胶质、沥青质组分（SARA）组成所能反映的体系的稳定性是相一致的。

STUDY OF THE COLLOIDAL STABILITY OF RESIDUES THROUGH MASS FRACTION NORMALIZED CONDUCTIVITY

This paper presents a novel method for detection of asphaltene precipitation in residues, which is based on measurement of the electrical conductivity of the residua solution as a function of added precipitant, n-heptane. The maximum of the mass fraction normalized conductivity of the solution is found to be the beginning point of asphaltene precipitating. Then the ratio of n-heptane to residue when the maximum of the mass fraction normalized conductivity of the solution gained can be defined as the indication of the stability of residue. Four kinds of sample are studied by this method. DaQing VR and the maltene of Middle East VR are the most stable because they contain little n-C7 asphaltene. Middle East VR is more stable than Middle East AR for it contains less saturate. The result is consistent with the characteristics reflected from the saturate, aromatic, resin and asphaltene constitutes of them.