A Review of Cellulose Extraction Pretreatment Methods

Cellulose is the most abundant natural fiber on earth which considered a renewable source for obtaining environmentally friendly products. The extraction of pure cellulose fibers from lignocellulosic materials requires the application of special extraction methods. However, several challenges arise during cellulose extraction processes. To overcome these problems and make it easier to layer the cell wall and release the cellulose micro and nano structures, in many recent researches, various pretreatment methods are used considering their application. Pretreatment methods can change the structural organization, crystallinity, and polymorphism of cellulose. In addition, it can change the various properties of pretreated raw materials. Therefore, it is very important to know the types of pretreatment methods. Therefore, in the present study, by using the content analysis method and reviewing the most important related works, the types of pretreatment methods necessary for the extraction of cellulose were reviewed and categorized. The results of the present work have been presented for the researchers active in the field of cellulose/polymer micro and nano composites, who need to extract a variety of micro or nano cellulosic structures to advance their research.