Preparation of 3-D porous PVDF/TPU composite foam with superoleophilic/hydrophobicity for the efficient separation of oils and organics from water

Nowadays, oils and organics pollutions have become more serious, which causes great threats both to the ecological environment and human life. To solve this problem, development of absorbent materials with high absorption capacity and good recyclability for large-scale oils and organics separation from water still remains large challenge. In this work, we propose a facile and low-cost method to prepare 3-D PVDF/TPU composite foam with superoleophilicity (0°) and hydrophobicity (143°) by combining vacuum-assisted solution casting and particle leaching techniques. The proposed PVDF/TPU composite foam shows high absorption capacity toward different of oils and organics, and its maximum absorption capacity can achieve 55 g/g for dichloromethane, which is attributed to its high porosity (95%) and excellent interconnectivity. The absorbed oils and organics can be readily removed by simply squeezing the PVDF/TPU composite foam due to its outstanding elasticity, suggesting that it has prominent recyclability. More importantly, the composite foam can quickly and continuously separate oils and organics from water through a peristaltic pump and has a high separation efficiency of 98.5% even after 10 cycles, which indicating a promising prospect for cleaning the large-scale oils and organics pollutions. Furthermore, the composite foam also can be applied to separate surfactant-stabilized oils and organics in-water emulsion. These results showed that the PVDF/TPU composite foam has the potential to be widely applied in practice for oils and organics separation.