Low-cost fluorinated diatomaceous earth polyurethane foam for the absorption of oil

In the present work, we intend to focus on the synthesis, characterization, and application of a high-performing hydrophobic and oleophilic polyurethane foam functionalized with diatomaceous earth and fluorosilane, which are eco-friendly and low-cost materials for their potential use as absorbents for hydrophobic materials. The scanning electron microscopic studies and thermogravimetric analysis showed that the surface-modified polyurethane has a significant micro–nano-structure and surface functionalization, and the water contact angle measurement showed an increase in hydrophobicity due to the fluorosilane-functionalized diatomaceous earth particles anchoring onto the polyurethane foam. Also, the thermogravimetric analysis revealed an increased thermal stability due to the surface functionalization. The novel fluorosilane—diatomaceous earth—polyurethane foam exhibited a silver mirror-like effect when immersed into water due to inherent hydrophobicity and had an enhanced absorption of oil and organic solvents compared to the unmodified polyurethane. This research presents the successful synthesis of surface-modified polyurethane for its suitability for oil absorption capacity for cleaning the oil pollutants from water and for organic solvents clean-up purposes. Graphical abstract Overview of the research approach, which represents stepwise synthesis of the polyurethane (PU) foam surface modified with diatomaceous earth (DE) and fluorosilane (FS) to form low-density and high-absorbing surface-functionalized PU foam exhibiting enhanced oil absorption making this novel composite as a potential candidate for crude oil clean-up and recovery process.