Highly Efficient Preparation of Functional and Thermostable Cellulose Nanocrystals via H2SO4 Intensified Acetic Acid Hydrolysis

Hui Wang; Hongxiang Xie; Haishun Du; Xumei Wang; Wei Liu; Yaxin Duan; Xiaoyi Zhang; Lin Sun; Xinyu Zhang; Chuanling Si

doi:10.1016/j.carbpol.2020.116233

Highly Efficient Preparation of Functional and Thermostable Cellulose Nanocrystals via H₂SO₄ Intensified Acetic Acid Hydrolysis

Carbohydr Polym. 2020 Jul 1:239:116233. doi: 10.1016/j.carbpol.2020.116233. Epub 2020 Apr 4.

Authors

Hui Wang¹, Hongxiang Xie², Haishun Du³, Xumei Wang⁴, Wei Liu⁴, Yaxin Duan⁴, Xiaoyi Zhang⁴, Lin Sun⁴, Xinyu Zhang⁵, Chuanling Si⁶

Affiliations

¹ Tianjin University of Science and Technology, Tianjin 300457, China; Key Laboratory of Bio-Based Material Science & Technology (Northeast Forestry University), Ministry of Education, Harbin 150040, China.
² Tianjin University of Science and Technology, Tianjin 300457, China. Electronic address: xiehx@tust.edu.cn.
³ Department of Chemical Engineering, Auburn University, Auburn, AL 36849, USA.
⁴ Tianjin University of Science and Technology, Tianjin 300457, China.
⁵ Department of Chemical Engineering, Auburn University, Auburn, AL 36849, USA. Electronic address: xzz0004@auburn.edu.
⁶ Tianjin University of Science and Technology, Tianjin 300457, China; Key Laboratory of Bio-Based Material Science & Technology (Northeast Forestry University), Ministry of Education, Harbin 150040, China. Electronic address: sichli@tust.edu.cn.

PMID: 32414449
DOI: 10.1016/j.carbpol.2020.116233

Abstract

A highly efficient and sustainable strategy for the production of functional and thermostable cellulose nanocrystals (CNCs) was developed in this work. In which, the acid hydrolysis system composed with small doses of H₂SO₄ (5-10%) and large amounts of easily recoverable acetic acid (70-90%) was used to hydrolyze cellulose pulp at 80 °C for several hours. The rod-like CNCs were obtained with the length of 150-500 nm and diameter of 5-20 nm in high yield (Y_max = 81%). The resulted CNCs showed high thermal stability and excellent dispersion stability in both aqueous and organic phases. The acetic acid in the hydrolysis system can be completely recovered by vacuum distillation, and the dosage of sulfuric acid can be reduced significantly compared with the traditional sulfuric acid hydrolysis. Thus, this approach is promising for the large-scale and sustainable preparation of CNCs with excellent water dispersibility and good thermal stability, with less environmental issues.

Keywords: Cellulose nanocrystals; Mixed acid hydrolysis; Organic acid hydrolysis; Surface functionality; Thermal stability.