The effectiveness of the organosolv process in wheat straw delignification optimizing temperature and time reaction

The present study investigates the organosolv treatment of wheat straw, for the optimization of cellulose delignification, which will serve as raw material for the paper industry. The influence of temperature (130–180 °C) and reaction time (60–180 min) was investigated using an 87% acetic acid solvent concentration and a solid–liquid ratio of 1:25. The experiments were designed and evaluated using Response Surface Methodology with Central Composite Design (CCD). The response parameters were Kappa number and viscosity (ml/g). The optimal parameters of operation were 146.43 °C and 180 min of obtaining pulp with a Kappa number value of 16.30 and a viscosity value of 430.05 ml/g, with a value for holocellulose of 94.3% and 5.4% for Klason lignin. The samples were characterized by Fourier Transform Infrared (FTIR) and Scanning Electronic Microscopy (SEM). Visible effects of treatments were observed through SEM microscopy while the 1595 cm −1 and 1510 cm −1 peaks were reported to be bonds from lignin that presented a reduction in height and area peaks with the treatments. This study determined optimal temperature and time for the organosolv process at the lab scale and the viability of commercial delignification of cellulose from wheat straw with a constant solvent concentration and a constant solid–liquid ratio. Graphical abstract