Scalable Superhydrophobic CB/PVFM Sponge for Enhanced Cleanup of Crude Oil Exploiting Photothermal and Electrothermal Effects

Heavy oil spill recovery is a global challenge because of its high viscosity and low fluidity. Herein, we demonstrated a method to develop a solar and Joule heating superhydrophobic carbon black/polyvinyl formal sponge (S-CB/PVFM) for cleanup of highly viscous crude oil. At an optimal amount of CB (200%) in polyvinyl formal, S-CB/PVFM revealed a highly porous sponge-like structure. The as-prepared sponge can effortlessly separate light and heavy oils from an oil–water mixture. The surface temperature of S-200% CB/PVFM increased to 77 °C under exposure to 1 kW m–2 of light intensity and 154 °C by applying a voltage of 12 V, causing the viscosity of the crude oil to decrease and allowing it to be absorbed quickly. In the continuous crude oil cleaning process, the as-prepared sponge revealed a crude oil collection rate of 0.600 g/min and 4.954 g/min under photothermal and electrothermal heating, respectively. The results indicate that this approach can effectively reduce viscosity and recover crude oil in unfavorable weather conditions. Using cost-effective CB and advanced PVFM technology, we have created a large-scale sample (18 cm diameter) to cleanup oil spills in vast areas, providing hope for a cleaner and more sustainable future.