Nanocellulose nanocomposite aerogel towards efficient oil and organic solvent adsorption

In this work, in order to ameliorate the hydrophobic property and adsorption capacity of nanocellulose (NC) aerogel, the nanochitosan (NCS) and reduced graphene oxide (rGO) have been introduced into the NC aerogel to construct the NC/NCS/rGO nanocomposite aerogel by a hydrothermal method combined with freeze-drying method. The optimal conditions including the effect of NC and NCS weight percentages for preparation of NC/NCS/rGO nanocomposite aerogel with good porous microstructures and excellent adsorption capacities have been evaluated. The results demonstrate that the NC/NCS/rGO nanocomposite aerogel produced under the fabrication condition of 0.1 wt% NCS and 0.05 wt% NC exhibits a very low density of 9.3 mg cm−3, a high hydrophobicity with a large water contact angle (115.26°) and the high adsorption capacities of 171.85 ± 3.02, 159.64 ± 1.83, 153.22 ± 2.92, 149.60 ± 6.26, 139.93 ± 3.69, 132.47 ± 3.45, 176.82 ± 4.66, 128.70 ± 0.69, and 120.34 ± 5.57 g g−1 to mineral oil, sesame oil, acetone, ethyl acetate, thiophene, pump oil, waste pump oil, kerosene, and ethyl alcohol, respectively. In addition, this aerogel adsorbent could efficiently and continuously remove/collect the oil from wastewater confirmed by a designed oil/water pump apparatus. As a consequence, this NC/NCS/rGO nanocomposite aerogel has a potential application in the oil and organic solvent adsorption.