Enhanced oils and organic solvents absorption by polyurethane foams composites modified with MnO2 nanowires

The severe environmental and ecological problems, derived from oil spills and organic solvents leakage, have occurred in many parts of the world. It is urgent to seek appropriate ways to resolve oily wastewater and organic solvent pollution. A versatile oil-absorbing material which can separate the oily wastewater effectively and quickly is in high demanded for this issue. In this work, we report a facile and inexpensive to fabricate an effective and recyclable oil-absorbent, namely MnO2 nanowires/polyurethane (PU) foam composites, using a PU sponge as a porous substrate and MnO2 nanowires as modifiers. The hydrothermal method is employed to synthesize MnO2 nanowires and then foaming technology is used to fabricate MnO2 nanowires/PU foam composites. In order to enhance the hydrophobic and oleophilic properties, the surfaces of MnO2 nanowires are chemically modified using silane coupling agent (KH 570). The present MnO2 nanowires/PU foam composites not only effectively separate oils from water as expected, but also possess a very high absorption capacity for the removal of organic solvents from water up to 40.15 times its own weight. More importantly, the obtained MnO2 nanowires/PU foam composites is demonstrated to have excellent oil recoverability and absorbent regenerability, making them versatile and comprehensive absorbents to satisfy various practical oily wastewater and organic solvent separation requirements.