Is nanocellulose a good substitute for non-renewable raw materials? A comprehensive review of the state of the art, preparations,and industrial applications

Nanocellulose has many excellent properties and functions and is a good candidate material. In this review, three major groups of nanocellulose are evaluated in detail: cellulose nanofiber (CNF), cellulose nanocrystals (CNC) and bacterial nanocellulose (BNC). We concentrated on the preparation and separation techniques to produce nanocellulose including mechanical, biological, and chemical treatment methods. These traditional single treatment methods have many restrictions such as long treatment time, high energy consumption and low recovery rate of nanocellulose. In order to overcome these defects, researchers combined mechanical treatment with biological and chemical treatment methods to prepare nanocellulose. The structure and properties of nanocellulose were significantly improved by the combined treatment method. Besides, the use and impact of nanocellulose in five industrial sectors: composite material, food industry, biomedical science, wasterwater treatment as well as energy and electronics are described and discussed. The future research directions and new applications challenges of this sustainable nanocellulose are described in detail in this paper in the original manuscript.