Design and synthesis of temperature-responsive Janus nanoparticles with high salt tolerant for enhanced heavy oil recovery

Enhancing the recovery efficiency of heavy oil reservoirs remains one of the foremost challenges confronting the petroleum industry. Nanoparticles have garnered considerable attention as potential oil displacement agents, drawing numerous researchers to the field. In this study, temperature-responsive SiO 2 Janus nanoparticles (JNs) were successfully prepared through the Pickering emulsion template method and atom transfer radical polymerization (ATRP) reactions. Experiments on the interfacial tension (IFT) of oil-water systems indicate that JNs exhibit good dynamic interfacial activity. Furthermore, the JNs exhibit remarkable emulsification capabilities for heavy oil, facilitating the formation of stable emulsions. Notably, the modified nanoparticles exhibit a degree of salt resistance, even up to a mineralization of 1.55 × 10 4  mg/L. Additionally, their temperature-responsive properties enable their utilization for high-temperature emulsification and low-temperature demulsification, making them well-suited for oilfield field operations. To visualize and simulate the underground oil displacement process, a microscopic displacement visualization experimental apparatus was employed. Notably, the addition of just 0.03 wt% of Janus nanoparticles resulted in a significant enhancement of the recovery rate by 16.49%. The research findings suggest that the JNs developed in this study exhibit promising application prospects and commercial value in terms of enhancing oil recovery efficiency.