Novel Janus Carbon Nanofluids from Waste Plastics as Sustainable Nano-Agents for Enhanced Oil Recovery: Scale-Up Synthesis and Performance Evaluation

Abstract

Abstract This research reports a new type of useful nanomaterials from waste plastics, Janus carbon nanofluids, and demonstrate potentials of the Janus carbon nanofluidsas high-effective alternative nano-agents for EOR application at reservoir condition. A novelsustainable cost-effective method has been developed to scale-up synthesis of Janus carbon nanoparticles (JC-NPs) from the waste plastic feedstock by combined pyrolysis, chemical functionalization and pulverization processes, which allow to produce the JC-NPs in mass quantity in industrial scale. The Janus nanostructures have been characterized and confirmed by multiple techniques including scanning electron microscopy (SEM), Langmuir-Blodgett (LB) curve, contact angle and interfacial tension (IFT) measurements. Unique dual properties of nanoparticulate and surfactant-like behavior of the JC-NPs have been observed and confirmed. Formulated as nanofluids in brine suspension, the JC-NPs can be directed and assembled at interfaces of rock/fluid or water/oil. Contact angle measurement has shown that the JC-NPs remarkably alternate the wettability of rock surface, and interfacial tension measurements have shown that the JC-NPs can lower the IFTs between brine and crude oil at simulated reservoir conditions. With low concentration of the JC-NPs in nanofluid formula, EOR performance tests have been performed to evaluate the efficiency of the nanofluids for oil replacement in carbonate reservoir with a microfluidic device, and the results have demonstrated that the Janus nanofluids at low concentration could remarkably promote the oil replacement in simulated carbonate reservoirs. The waste plastic conversion appears as an attractive way to produce useful, valuable Janus carbon nanomaterials to decrease the carbon footprint and contribute to the transition toward a resource-efficient chemical industry.