Preparation of eco-friendly mesoporous expanded graphite for oil sorption

Due to its unique properties, expanded graphite (EG) is a promising material that could be used in various applications. Traditional EG production methods had numerous problems in terms of saving energy and reducing pollution. This article provides an efficient and energy-conserving preparation process to obtain EG, in which flake graphite is intercalated and expanded at room temperature. The flake graphite was expanded using a simple and effective method in which graphite intercalation and expansion are accomplished using a binary system of concentrated sulfuric acid (H2SO4) and inorganic salts, specifically sodium peroxydisulfate (Na2S2O8). The optimal conditions were at room temperature, with a mass fraction of 14% of graphite to Na2S2O8 and a mass fraction of 5% of graphite to H2SO4. This gave a maximum expanded volume of 140 mL/g. XRD, SEM, FT-IR, and Raman spectroscopy were used to characterize the expanded graphite's microstructures, morphology, and functional groups. After being expanded, the flake graphite transformed into a worm-like structure, and the graphite sheets were only slightly damaged. When used as an oil sorbent, EG has a high capacity to absorb oil and can quickly and effectively absorb oil from water. [GRAPHICS] .