Unique emulsifying and interfacial properties of SP oil: Enhanced emulsification at higher temperatures

•SP oil exhibits higher PIPs and IFTs at higher temperatures.•The stronger intermolecular interactions present within the asphaltene of SP oil.•The optimal ratio of asphaltene to resin is determined to be 1:5. The behavior of SP crude oil defies the typical expectation that crude oil should exhibit lower phase inversion points (PIPs) and interfacial tension (IFT) at higher temperatures. To investigate these unique characteristics, emulsification experiments were conducted on SP oil at different temperatures. The emulsifying properties of various components of SP oil and maltene, with varying asphaltene contents, were further determined. The PIP of SP oil was observed to increase with temperature, ranging from 55 % at 50 °C to 85 % at 85 °C. Among the components of SP oil, only asphaltenes exhibited a slight resistance to the reduction of the PIP with increasing temperature. For maltene, the addition of asphaltene led to a higher PIP with increasing temperature. When the optimal mass ratio of resin to asphaltene was 5:1, the PIP increased from 65 % at 30 °C to 75 % at 60 °C. Furthermore, the interfacial properties of SP oil and its components at different temperatures were analyzed. The experimental results demonstrated that the IFT of SP oil increased with temperature. The dynamic IFT exhibited an increasing trend over time while maintaining relative stability. Among the components of SP oil, only asphaltenes exhibited an increase in IFT over time. For maltene, the addition of asphaltene resulted in an increase in IFT with increasing temperature.