Sugarcane bagasse oxidation using a combination of hypochlorite and peroxide

Reactive oxygen species (ROS) such as singlet oxygen (1O2), superoxide (O2−), hydroxyl radicals (OH), or hypochlorite ion (OCl−), can remove both hemicellulose and lignin from lignocellulose. Ox–B (US Patent 6,866,870), an ROS producing solution containing sodium hypochlorite and hydrogen peroxide, was investigated for its ability to oxidize sugarcane bagasse. Treatment with equivalent amounts of hypochlorite produced similar results. Ox–B differentiated from hypochlorite when low concentration treatments were used and they were followed by a caustic wash. Cellulases hydrolyzed 80–100% of the cellulose present after Ox–B/caustic treatment compared to 40% or less for NaOCl/caustic treatment. Ox–B treatment was temperature independent and complete within 3 h. It was pH dependent, with best results obtained when the pH was controlled at 8. Although highly effective, in order for Ox–B to be industrially feasible for alcohol production, the chemical cost must decrease to justify its use.