Siberian Federal University

The kinetic regularities of the process of abies wood delignification in the “formic acid-hydrogen peroxide-water” medium at the presence of the MnSO4 catalyst at the temperature range 70–100 °C were established. It was determined that the delignification process is satisfactorily described by the first order equation. The reaction rate constants vary from 1.8 to 10.2∙10–4 min‑1, the activation energy is 85 kJ/mol. Mathematical optimization of the process of abies wood delignification, as a key stage of nanofibrillated cellulose production, was carried out by Box-Behnken statistical method. Under the optimal conditions: HCOOH 30 wt.%, H2O2–9 wt.%, LWR 15, temperature 100 °C, 4 h, the cellulose product with a lignin content of 1.2 wt.%, hemicelluloses 5.2 wt.%, cellulose 93, 1 wt% was obtained. The average hydrodynamic diameter of particles of nanofibrillated cellulose produced from abies wood by acid hydrolysis followed by ultrasonic treatment is 82 nm