Innovative Combined Pretreatment of Sodium Hydroxide and Sodium Perborate for Enhanced Methane Yield from Lignocellulosic Biomass: A Time‐Series Kinetic Analysis

Alkaline pretreatment, particularly with strong alkalis like sodium hydroxide (NaOH), is common for boosting methane (CH 4 ) yield from lignocellulosic biomass by removing lignin. However, strong alkaline pretreatments can be problematic for biorefineries due to material loss or incomplete breakdown. This study introduces a combined pretreatment using both NaOH (strong) and sodium perborate (SPB) (mild) on hazelnut shell biomass to enhance lignocellulose degradation and CH 4 yield. The combined pretreatment with 2.5% NaOH and 2.5% SPB significantly increases CH 4 yield (222.0 CH 4 /g volatile solids (VS), p < 0.05) compared to NaOH alone (140.0 mL/g VS). The synergistic effect of combined low concentrations of NaOH and SPB promotes favorable lignocellulose degradation, demonstrating a promising pathway for enhancing CH 4 yield. Furthermore, cumulative CH 4 yields following pretreatments are modeled using time‐series analysis, and the model performance is compared against a modified Gompertz model (MGM). The time‐series model shows superior prediction accuracy with lower error rates (root mean squared error: 0.57 vs 3.20) and higher correlation coefficients ( R 2 : 0.9991 vs 0.9999) compared to MGM, making them recommended for predictions of CH 4 yield in anaerobic digestion processes.