OGF nanocomposite foam for enhanced recyclability and oil-recovery

Abstract

Continuous oil spills around the world not only affect the air and water quality but also lead to massive destruction of the natural ecosystem of shallow and deep-waters. Existing methods for oil sorption lack ease of reusability, selectivity and mass production. Thus, there is an urgent need to develop economical, scalable, and efficient oil sorbent material. Here, we report a polymer nanocomposite foam of oxidised graphene frameworks (OGFs) derived using agro-waste. The OGFs impart porosity, hydrophobicity, and super-oleophilicity to the foam, resulting in enhanced sorption capacity of different categories of oils such as lubricants, organic solvents, vegetable oils and locomotive oils. Sorption capacity for DCM, diesel and mustard oil was found to be 27.4, 6.18 and 6.4 gg-1 respectively. Surface-wetting properties improved to super-oleophilic and hydrophobic, with an oil contact angle of 0° and water contact angle of 120 ± 3°, respectively. Compared to pristine polymeric foam, the nanocomposite foam shows ∼80% increase in tensile modulus and compressive strength, making it durable during handling and recycling. It is found to be stable in highly acidic, basic and saline conditions and shows excellent sorption performance even after 500 cycles, making it attractive for commercial applications. OGF-incorporated nanocomposite foam has demonstrated superb sorption and mechanical with excellent recycling properties, which makes it suitable for recovering oils and organic solvents from spills and resolving the problem of oil pollution in sea and surface water with recovery of precious resources. Our findings pave the way for the direct implementation of developed nanocomposite foam for commercial application.