2.2. WAS Pretreatment. A glass reactor with working volume of 300 mL was used for thermo-alkaline pretreatment. NaOH solution (5N) was used to adjust pH of sample to a value around 10. After that, sample was homogenized for 24 h at ambient temperature (28°C) and 2 h at 105°C. These conditions were optimized in a previous study [21].