Kinetic study of oxalic acid pretreatment of moso bamboo for textile fiber

In this study, samples of moso bamboo were hydrolyzed for textile fiber with oxalic acid under various process conditions. Saeman hydrolysis models were applied to predict the percentage of xylan remained in the substrate after pretreatment and the net xylose yield in the liquid stream. Kinetic constants for Saeman hydrolysis models were analyzed by an Arrhenius-type expansion which include activation energy and catalyst concentration factors. The result showed that the degradation activation energies of xylan and xylose were 97.27 and 136.38 kJ/mol, respectively. Then the kinetic of mathematical models were obtained. Furthermore, the reaction parameters of oxalic acid concentration (1–4 % w/w), reaction temperature (150–180 °C), and reaction time (5–60 min) were handled as a single parameter, combined severity, which ranged in the present study from 0.86 to 1.62. Using combined severity parameters, an optimal condition was achieved which was as the followings: oxalic acid 2.0 % w/w, 170 °C, and 20 min. Under these conditions, 2.3 g glucose/L and 13.65 g xylose/L were produced in the hydrolysate fraction, 54.1 % glucan and 10.8 % xylan were produced in the residue fraction.