Dissolution of Microcrystalline Cellulose in Phosphoric Acid—Molecular Changes and Kinetics

Molecules

Junhua Zhang¹  Jingqiang Zhang¹  Lu Lin¹  Tianming Chen¹  Jun Zhang¹  Shijie Liu¹  Zhenjiang Li¹ 

[1] ¹Department of Resources Science and Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, Guangdong Province, China

关键词: kinetic;    MCC;    phosphoric acid;    decrystallization;    structural change;   

DOI  :  10.3390/molecules14125027

来源: mdpi

【 摘 要 】

In this study, we aimed to dissolve microcrystalline cellulose (MCC) with phosphoric acid to obtain high-quality fermentable saccharides. MCC was directly dissolved in phosphoric acid (the concentration was 83%) for 10 hours at temperatures of 30, 50, and 70 °C. The structural changes of MCC were determined in detail with X-ray powder diffraction, solid-state cross-polarization magic angle spinning ¹³C-NMR, and X-ray photoelectron spectroscopy. The kinetics of MCC decrystallization during treatment with phosphoric acid was also compared at 30, 50, and 70 °C. With the assumption of first order kinetics, the Arrhenius parameters of K, A₀ and E_a were calculated. The rate constants of decrystallization reaction (K) were 0.06, 0.17, and 0.12 h^-1 respectively. The pre-exponential factor (A₀) was 1.2 × 10⁶ h^-1, and the activation energy (E_a) was 42.4 kJ/mol.

【 授权许可】

CC BY   
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.