Effect of the Evaluation and Mechanism Analysis of a Novel Nanohybrid Pour Point Depressant on Facilitating Flow Properties of Crude Oil

Novel nanohybrid pour point depressants (PPDs) were prepared by combining ethylene–vinyl acetate (EVA) copolymers with nano-SiO2 particles, and a series of experiments were carried out to test the effects of EVA/nano-SiO2 (E–S) hybrid PPDs on model waxy oil containing 25 wt % wax and crude oil. The results showed that optimal PPD performance was attained at the concentration of 0.08 wt %, which can suppress the formation of gelling effectively and improve the fluidity of both oils. The presence of the E–S hybrid PPD effectively modulated the crystal morphology to the orientation that was conducive toward reducing the gelling temperature and inhibiting the formation of the network structure. Meanwhile, the PPD adsorbed on the surface of asphaltene and resin can prohibit the self-association of asphaltene and resin, which further improved the fluidity of crude oil.