Solar-assisted efficient cleanup of high-viscosity oil spills using magnetic porous biochar

Efficient cleanup of oil spills is still a global challenge due to the high viscosity of crude oil and complicated topographic features. Herein, magnetic porous carbon powders (MPCs) with photothermal effect prepared at a Fe(NO3)3: bamboo mass ratio was 1/1 carbonized at 700 °C. After modifying with the n-octadecylamine, the oleophilic MPCs exhibited rapid and selective absorption of different oils from polluted water, with an optimal absorption capacity of 3.2–8.1 g/g. Since oil's viscosity is highly temperature-sensitive, MPCs with photothermal characteristics offer apparent advantages in absorbing high viscosity oil. Moreover, due to the incorporation of magnetic components, powder-like MPCs can be conveyed to a specified oil pollution spot (including gaps or cracks) conveniently and collected through a remote magnetic field. This work demonstrates a simple and low-cost way of designing and producing oil/water separation materials, particularly floating high-viscosity oil recovery.