Superelastic, ultralight, superhydrophobic bacterial cellulose aerogel for efficient absorption of oil from water

The development of green, efficient and reusable absorption materials remains a challenge in the field of oilwater separation. Herein, a superhydrophobic bacterial nanocellulose (BC)-based aerogel (s-BPGA) was developed using directed freeze-drying method, followed by modification through chemical vapor deposition (CVD). Polyethyleneimine (PEI) and gamma-glycidoxypropyltrimethoxysilane (GPTMS) was used as crosslinkers to enhanced the mechanical strength of s-BPGA. The prepared aerogel had low density (5.8 mg cm-3) and robust mechanical strength with almost 100 % shape recovery after 90 % compression strain, and it showed excellent absorption to n-hexane, aviation kerosene and tetrachloromethane and other oils and organic solvents. The absorption capacity of s-BPGA aerogel was in the range of 80.91 (n-hexane)-203.30 (tetrachloromethane) g g-1. After undergoing 20 absorption-desorption cycles by simple mechanical extrusion method, it almost retained its original shape and absorption capacity, demonstrating remarkable recyclability.