Calcium peroxide pretreatment to facilitate the delignification and enzymatic hydrolysis of wheat straw

Calcium peroxide (CaO2) pretreatment was employed to remove lignin and subsequently facilitate enzymatic digestibility of wheat straw. An optimal condition was obtained at 130°C for 10 min with 0.35 g CaO2/g dried material of wheat straw and a 1:8 solid-liquid ratio. Under this condition, 57.8% of initial lignin, 7.2% of initial glucan, and 30.6% of initial xylan were removed from CaO2 pretreatment, respectively, meanwhile, a glucose recovery of 90.6 % and a xylose recovery of 65.9 % were obtained from the subsequent enzymatic hydrolysis of treated wheat straw, respectively. CaO2 pretreatment was proved to be a very effective method in delignification and improving enzymatic digestibility. Compared to raw material, the complex structure of lignocellulose was drastically disrupted with a wide emergence of scaly bulges and fully exposed microfibers, which still retained in the solid.