Pretreatment of corn stover with acidic electrolyzed water and FeCl3 leads to enhanced enzymatic hydrolysis

Abstract

Pretreatment has been viewed as the most efficient strategy for lignocellulosic biomass-to-fermentable sugars conversion. In this study a novel pretreatment with acidic electrolyzed water (AEW) and FeCl3 was proposed and tested to deconstruct the recalcitrance of corn stover and enhance its subsequent cellulose-to-sugar conversion. The effects of AEW pH and FeCl3 concentration on hemicellulose degradation were investigated, and the results showed the highest hemicellulose removal (93.40 %) and recovery (93.04 %) were achieved at AEW pH 2.30 and FeCl3 concentration 0.05 mol/L. Further research on the properties of AEW solutions with FeCl3, including their pH, ORP, and DO revealed the synergistic effects of strong acidity and high oxidizing capacity of the solution could boost hemicellulose breakup and enhance the enzymatic hydrolysis of cellulose (92.00 %) by removing most of hemicellulose and increasing the accessibility and digestibility of cellulose. Therefore, these studies prove AEW coupled with FeCl3 pretreatment is an effective and promising approach in biomass-to-biofuel process.