Effective cleanup of viscous crude oil spills remains a persistent and crippling challenge. Herein, this work presents a Joule-heated superhydrophobic flower-like Cu8(PO3OH)2(PO4)4·7H2O-coated copper foam (SHB-CF@CP) for rapid cleanup of viscous crude oil spills via a facile strategy. The SHB-CF@CP shows outstanding water repellency and excellent stability of hydrophobicity in harsh environments. Due to the high electrical conductivity and thermal conductivity, it requires lower power energy consumption (less than 1 V of voltage input) to raise the temperature significantly, which dramatically reduces the viscosity of crude oil (from ∼2 × 105 to ∼60 mPa s) and then increases the oil absorption rate, effectively avoiding the poor mobility and ineffective absorption of viscous crude oil. Notably, the SHB-CF@CP can achieve continuous and quick cleanup of crude oil under in situ pumping force. The high-performance Joule-heated SHB-CF@CP sorbent with a strong porous skeleton, corrosion resistance, and low predicted operational costs holds a promise of promoting its practical applications in the cleanup of intractable and large-area viscous oil spills.
Yahui Cai,Jianfei Wu,Kaili Wang,Youming Dong,Jundie Hu,Jiafu Qu,Dan Tian,Jianzhang Li,Qiliang Fu
Designing highly porous materials is of great importance for liquid separation, water purification, and disinfection, such as spill oil cleaning and recycling, seawater desalting, and oil/water separation. However, a remaining challenge is to produce porous materials with the characteristics of fast absorption, continuous directional transport, and self-release of viscous liquid. Herein, a functional cellulosic composite is reported by the chemical treatment and functionalization of wood resulting in a smart wood that can thermally self-release and separate high viscosity oil. The smart wood has a high absorption speed of 1398 mL/(m 2 ·s) (ethylene glycol) and a maximum absorption capacity of 47.2 g/g (chloroform) due to its intrinsic vertical micro/nanoscale channel structure, low tortuosity, and high porosity. Moreover, the switchable wettability is achieved by the surface coating of poly(N-isopropylacrylamide) on the porous wood, which enables the collection and removal of oil from the oil/water mixture. The high viscosity oil can be automatically released due to the passive oil release at room temperature. The release capacity of the smart wood remains above 91% after 15 cyclic tests. We envision that this functional smart wood could be extended to a wide range of applications in smart hydrogels, microfluidics, artificial drug release, and environmental restoration.