胶质对沥青质稳定性的影响

为了进一步研究胶质与沥青质之间的相互作用对沥青质稳定性的影响，在分析表征沥青质和胶质的平均结构单元并计算溶解度参数的基础上，向沥青质模型油（沉积物计为AS沉积物）中分别加入胶质NBR和胶质VRR得到AS+NBR沉积物和AS+VRR沉积物，通过分析沉积物颗粒粒径分布，考察胶质对沥青质稳定性的影响程度。结果表明：沥青质的芳香性最强、溶解度参数最大（20.61 MPa1/2），胶质VRR的芳香性和溶解度参数（17.80 MPa1/2）高于胶质NBR；在沥青质模型油中，随着胶质VRR浓度的增加，沉积物颗粒粒径减小，而胶质NBR的加入并不能使沉积物颗粒粒径变小，当其质量浓度达到1 000 mg/L时，沉积物颗粒粒径反而增加。3种沉积物的热重、凝胶渗透色谱（GPC）和X射线衍射（XRD）分析结果表明：胶质与沥青质之间存在缔合作用，使沉积物芳香片层厚度和直径减小、层间距增大，芳香片层数减小；3种沉积物的相对分子质量从大到小的顺序为AS沉积物＞AS+NBR沉积物＞AS+VRR沉积物。因此芳香性强、溶解度参数接近沥青质的胶质VRR能更好地分散稳定沥青质，使得沉积物颗粒粒径变小、石墨化程度减弱，从而不易沉积和结焦。

EFFECT OF RESIN ON ASPHALTENE STABILITY

It is generally acknowledged that the particle size of the deposit reflects the influence of resin on the stability of asphaltene. To further study the effect of the interaction between resin and asphaltene on the stability of asphaltene, based on the analysis of the average structural units of asphaltene and resin and the calculation of solubility parameters, resin NBR and resin VRR were added into a asphaltene model oil (its deposit known as AS deposit), resulting in the AS + NBR and AS + VRR deposits, respectively. The results showed that asphaltene had the strongest aromaticity and the largest solubility parameter (20.61 MPa1/2), and the aromaticity and solubility parameter (17.80 MPa1/2) of resin VRR was higher than that of resin NBR. In asphaltene model oil, with the increase of the mass concentration of VRR, the sediment particle size decreased. The addition of NBR did not make the deposit particle size smaller, but when the mass concentration reaches 1 000 mg/L, the sediment particle size increased instead. The results of TGA, XRD and GPC of three deposits showed that there was association between resin and asphaltene, which decreased the thickness and diameter of aromatic lamellae, increased the interlayer space, and decreased the number of aromatic lamellae. The order of the relative molecular weight of the three deposits was AS > AS + NBR > AS + VRR. It is concluded that the resin VRR, which has strong aromaticity and solubility parameter close to asphaltene, can disperse and stabilize asphaltene better, make the particle size and molecular weight of deposit smaller, and the degree of graphitization smaller, so it is not easy to deposit and coking.