为认识含有不同头部官能团的双亲分子对沥青质胶团分散性的影响,测定了添加十二烷基苯磺酸(DBSA)、十二烷基苯酚(DP)和十二醇的沥青质甲苯溶液的黏度变化规律,通过线性拟合得到其特性黏度[η],进而计算得到无限稀释情况下沥青质胶团直径。同时,对比了添加双亲分子前后沥青质甲苯溶液的比浓黏度随沥青质浓度的增加速率和胶团直径的变化。结果表明,酸性较强的十二烷基苯磺酸易于在沥青质表面吸附,在高浓度时,甚至可以明显增加沥青质胶团的直径。十二烷基苯酚吸附量较小,不能明显改变沥青质胶团的大小,而十二醇较难在沥青质表面吸附,对沥青质溶液的黏度几乎没有影响。由此可以初步推断,双亲分子头部官能团的酸性越强,其与沥青质的作用越强,在沥青质表面吸附的越多,其抑制沥青质聚并的能力越强。
In order to understand the effect of amphiphiles on asphaltene particle dispersity, the viscosities for the series of asphaltene solutions with addition of dodecyl benzene sulfonic acid (DBSA), dodecyl phenol (DP) and dodecanol were determined. The intrinsic viscosity [η] was determined through linear fitting of ηsp/p to p, and the diameters of asphaltene particles with and without amphiphiles were calculated through intrinsic viscosity. The slope of ηsp/p-p curve were also studied. The result showed that DBSA was apt to be absorbed on asphaltene surface, and enlarged the diameter of asphaltene particles at high DBSA concentration, while DP did not change the diameter of asphaltene particles because of its low absorption amount. And dodecanol almost had no effect on asphaltene solution viscosity, which indicated that it was not absorbed on asphaltene surface. It was concluded that the amphiphile with strong acid head group was apt to be absorbed on asphaltene surface, and thus was powerful to prevent asphaltene aggregation.