Sustainable Janus Nanoparticles from Waste Plastic for Enhanced Oil Recovery and CO2 Foam Stabilization

The research presents a novel sustainable method for producing Janus carbon nanofluids from waste plastics, which shows great promise as highly effective agents for enhanced oil recovery (EOR) and CO₂ foam stabilization. A cost-effective scalable synthesis process, combining pyrolysis, chemical functionalization, and pulverization, has been developed to generate Janus carbon nanoparticles (JC-NPs) from waste plastics on an industrial scale. These JC-NPs, when formulated as nanofluids in a brine suspension, can be applied at rock-fluid or water/oil interfaces. The JC-NPs notably alter the wettability of the rock surface, and interfacial tension (IFT) measurements indicate their ability to reduce the IFT between brine and crude oil under simulated reservoir conditions. EOR performance tests using a “reservoir-on-a-chip” microfluidic system demonstrated that Janus nanofluids, even at ultralow concentrations (0.001 wt %) in combination with a EOR surfactant, can significantly enhance oil displacement in simulated carbonate reservoirs. Additionally, the JC-NPs exhibited potential for maintaining CO₂ foam stability, which is highly beneficial for CO₂ injectivity in both CO₂ EOR and CO₂ geological sequestration. This innovative approach of converting waste plastics into valuable nanomaterials has the potential to reduce the carbon footprint and promote a more resource-efficient chemical industry.