Methane Enhancement through Sequential Thermochemical and Sonication Pretreatment for Corn Stover with Anaerobic Sludge

The present research emphasized the utilization of a novel sequential thermochemical and sonication pretreatment technology to enhance methane production from corn stover. The corn stover was thermochemically pretreated with sodium hydroxide to enhance its lignocellulosic digestibility. Due to thermochemical pretreatment, 65.45% lignin removal and 36.33% hemicellulose solubilization was observed and further five sonication levels were employed (25, 45, 60, 90, and 120 min). All pretreatments were found significant (P < 0.05) to enhance methane production from 14.78% to 73.72% while thermo-NaOH pretreatment with 90 min sonication time was proven as the optimum pretreatment with specific methane production of 320 mL/g volatile solids (VS). Anaerobic digestion process stability was deeply monitored at 3 day intervals via total volitile fatty acids, alcohol production, pH, chemical oxygen demand, and VS removal.