| Agricultural crops and forest residues are of valuable resources to produce biofuel due to anaerobic digestion. But, the recalcitrance nature of these lignocellulose residues limits its enzymatic degradation. Therefore, efficient pretreatments prior to anaerobic digestion are essential. Hydrothermal-chemical pretreatments using Phenol (Ph), Sodium Hydroxide (SH), and Phosphoric Acid (PA), and combined pretreatments included Ph+SH and Ph+PA as chemical pretreatments were used for spruce wood. The samples were put into the autoclave at 134º C for 20 min. Acid hydrolysis, FTIR and SEM analyses were carried out. The results indicated that all pretreatments were effective lignin removal having the highest value for Ph (42.362%). Adding Ph to PA increased lignin... |
