Comparison of Calcium Oxide and Calcium Peroxide Pretreatments of Wheat Straw for Improving Biohydrogen Production

[Image: see text] Wheat straw was pretreated with either CaO(2) or CaO to improve biohydrogen production. Both CaO and CaO(2) pretreatments improved the biodegradability of the wheat straw. CaO pretreatment raised the H(2) yield by between 48.8 and 163.9% at CaO contents ranging from 2 to 4%. The highest H(2) yield [144 mL/g total solid (TS)] was obtained at 121 °C and 6% CaO. In addition, the highest H(2) yield from wheat straw pretreated at the same temperature and dosage of CaO(2) was 71.8 mL/g TS, which was higher than that of the control group (43.2 mL/g TS), with hot water (121 °C) treatment. Considering pretreatment costs and H(2) production potential, CaO was a better pretreatment agent than CaO(2).