基于特性黏度法计算沥青质胶团直径和溶剂化效应——分散体系活化状态表征

CALCULATION OF COLLOID DIAMETER AND SOLVATION EFFECT OF ASPHALTENE BY INTRINSIC VISCOSITY METHOD—CHARACTERIZATION OF PETROLEUM DISPERSION SYSTEM IN ACTIVE STATE

在委内瑞拉常压渣油中添加不同比例十八醇,考察十八醇对强化减压蒸馏效果的影响。结果表明,十八醇具有良好强化效果,最大蜡油净增收率为4.01%。测定渣油(沥青质)-甲苯溶液的黏度,根据Einstein黏度定律和Pals-Rhodes方程,计算得到了沥青质胶团直径D和溶剂化参数K,结果表明,特性黏度法测得的沥青质尺寸为沥青质胶核外吸附-溶剂化层的直径,其数值受溶剂化效应的影响,测定渣油-甲苯溶液黏度可以表征渣油体系中沥青质胶团尺寸。对于添加了十八醇的渣油体系,其沥青质胶团直径减小、溶剂化效应降低,变化趋势与减压蜡油净增收率有良好的对应关系,可以采用特性黏度法计算沥青质胶团直径和溶剂化效应,来预测石油分散体系的活化状态。

To strengthen the effect on vacuum distillation, 0.002% octadecanol was ezuela atmospheric residue oll, resulting in 4.01% more waxy oil yield. The colloid diameter D and solvation factor K of asphaltene were calculated by Einstein law of viscosity and Pals-Rhodes equation based on the measured viscosities of residue oil（asphaltene）-toluene solutions. The results show that the colloid diameter of asphaltene measured by intrinsic viscosity method is the one of adsorption-solvation layer around colloidal nucleus of asphaltene, affected by solvation effect. It is confirmed that the colloidal diameter of asphaltene can be characterized by the viscosities of residue-toluene solution. The trends that the addition of octadecanol reduces the colloidal diameter of asphaltene and solvent effect have a good relation- ship with the increase of waxy oil yield. The active state of crude oil dispersion system can be predicted based on the colloidal diameter of asphaltene and solvent effect calculated by intrinsic viscosity method.