The impact of the alkali NaOH on the structure and morphology of cellulose has been considered. Using X-ray spectroscopic microanalysis and electron microscopy, it has been determined that treatment of wood cellulose with aqueous solutions of NaOH allows to reduce the content of lignin in cellulose and significantly improve the topography of the fibers. A comparative analysis of alkali cellulose samples was conducted, obtained during treatment with NaOH solutions of 13.7% and 12.3% concentration for a process duration of 5.5 hours, at a temperature of 124 °C. It has been established that at the considered concentrations of NaOH, approximately ~75% and ~50% of lignin is removed from the original cellulose, respectively. The results of infrared spectroscopy indicate an increase in the amorphization of alkali cellulose. Alkali cellulose, formed at a NaOH concentration of 13.7%, exhibits superior morphological uniformity and a lower lignin content.

Keywords: wood cellulose, chemical treatment, alkalinity, lignin, X-ray spectral microanalysis, electron microscopy