Coupled H2O2 oxidation and UV/TiO2 film photocatalysis pretreatment: A sustainable strategy to enhance enzymatic hydrolysis of corn straw

Pretreatment is a critical stage in the conversion of lignocellulosic feedstocks to biofuels. Herein, a sustainable and efficient pretreatment strategy coupling H2O2 oxidation with UV/TiO2 film photocatalysis was developed to reduce the structural recalcitrance of corn straw. A synergistic interaction occurred between H2O2 oxidation and UV/TiO2 film photocatalysis, with hydroxyl radical (OH) playing a pivotal role in increasing the effectiveness of the combined pretreatment. The optimal pretreatment conditions were identified as a four-layer TiO2 film, 0.6 g/g H2O2 loading, pH 11, and a temperature of 65 °C for 6 h. At the optimal pretreatment parameters, lignin and hemicellulose removal reached 79.0 % and 65.3 %, respectively, which promoted an increase in glucose yield from enzymatic hydrolysis of straw to 85.6 %. Moreover, possible mechanisms underlying the H2O2 and UV/TiO2 film pretreatment of straw were proposed. Collectively, this pretreatment strategy offers a novel, efficient, and environmentally sustainable approach that introduces no environmental pollutants, providing valuable insights for the biomass refining industry.