Superhydrophobic Absorbent Based on Multiwall Carbon Nanotubes and Superlight Clay for Solar-Assisted Crude Oil Cleanup.

Frequent oil spills pose a serious threat to the ecological environment and to human health. Therefore, it is a global topic to develop adsorbents with photothermal and superhydrophobic properties for the effective absorption of a high-viscosity crude oil. Herein, for the first time, the multiwall carbon nanotubes (MWCNTs)-superlight clay (SLC) was prepared using a freeze-drying method. Then, it was modified with octadecyl trichlorosilane (OTS) to obtain a superhydrophobic adsorbent (OTS/MWCNTs-SLC). The surface temperature of OTS/MWCNTs-SLC reaches 70 °C quickly under 1 kW m^–2 solar irradiation, which is essential to lower the viscosity of crude oil. Consequently, the adsorbent material demonstrated a crude oil absorption capacity of 19 ± 0.4 g/g and a light/heavy oil absorption capacity of 10–26 g/g. Additionally, the superhydrophobic photothermal OTS/MWCNTs-SLC exhibited mechanical and chemical stability and enabled continuous crude oil recovery. The prepared OTC/MWCNT-SLC broadens the application of SLC and provides a strategy for crude oil cleanup. [ABSTRACT FROM AUTHOR]