Advanced superhydrophobic and multifunctional nanocellulose aerogels for oil/water separation: A review

At present, the research and development of adsorbents for oil/water separation are mostly focused on polymer materials. The third generation of aerogels are made from nanocellulose prepared from abundant and sustainable cellulose. At present, there is concern regarding the use of nanocellulose aerogels (NAs) in oil/water separation. To improve the selective absorbability, the NAs should be hydrophobically modified, and in this review, we summarized the progress made in hydrophobic modification methods. Additionally, the typical materials used for hydrophobic modification of NAs in recent years were reviewed, and then, we discussed the fabrication of nanocellulose composite aerogels (NCAs) with different properties for use in oil/water separation. Moreover, the additional desirable properties of NAs used in oil/water separation processes are systematically discussed according to the different separation requirements, and the conclusions regarding the relationship between the oil adsorption capacity and different NA parameters are summarized. Finally, the outlook for and challenges faced in the construction of efficient NAs for oil/water separation were put forward.