Microscopic dissolution process of cellulose in alkaline aqueous solvents and its application in CNFs extraction - Investigating temperature as a variable

Jinping Peng; Yihui Huang; Rongwei Fu; Jinqing Lu; Weiquan Wang; Wentao Zhu; Yuxuan Yu; Fan Guo; Haiyan Mai

doi:10.1016/j.carbpol.2023.121361

Microscopic dissolution process of cellulose in alkaline aqueous solvents and its application in CNFs extraction - Investigating temperature as a variable

Carbohydr Polym. 2023 Dec 15:322:121361. doi: 10.1016/j.carbpol.2023.121361. Epub 2023 Sep 4.

Authors

Jinping Peng¹, Yihui Huang², Rongwei Fu², Jinqing Lu², Weiquan Wang², Wentao Zhu², Yuxuan Yu², Fan Guo², Haiyan Mai³

Affiliations

¹ School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China; Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory, Jieyang 515200, China.
² School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China.
³ Department of Pharmacy, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China. Electronic address: maihy@mail.sysu.edu.cn.

PMID: 37839827
DOI: 10.1016/j.carbpol.2023.121361

Abstract

The target of this study is to gain a deeper understanding of the micro-dissolution process of cellulose in alkaline aqueous solutions and to develop a novel method for extracting cellulose nanofibrils (CNFs). Herein, the dissolution process of cellulose in alkaline aqueous solutions will be controlled by varying the temperature, and the undissolved cellulose will be analyzed to reveal the microscopic dissolution process of cellulose, and a novel process for extracting cellulose nanofibrils (CNFs) will be developed based on the findings. The crystalline structure of cellulose was gradually disrupted as the dissolution progressed, and the crystal form of cellulose changed gradually from cellulose I to cellulose II during the dissolution process, while all undissolved cellulose crystals remained as cellulose I. Cellulose, after its structure is disrupted during the dissolution process, will inevitably decompose into CNFs, and the microscopic dissolution process of cellulose follows a "top-down" dissolution sequence. The CNFs extraction method developed in this study can extract CNFs with high yield (>60 %) in a stable manner, as well as narrow particle size distribution, high crystallinity (>77 %), and good thermal stability. This study enhances the comprehension of the dissolution process of cellulose and paves a possible way for industrialization of CNFs production.

Keywords: Alkaline aqueous solvent; Cellulose; Cellulose nanofibrils; Dissolution; Extraction; Temperature.