Preparation of levoglucosenone through sulfuric acid promoted pyrolysis of bagasse at low temperature

Fast pyrolysis of bagasse pretreated by sulfuric acid was conducted in a fixed bed reactor to prepare levoglucosenone (LGO), a very important anhydrosugar for organic synthesis. The liquid yield and LGO yield were studied at temperatures from 240 to 350   °C and sulfuric acid loadings from 0.92 to 7.10   wt.%. An optimal LGO yield of 7.58   wt.% was obtained at 270   °C with a sulfuric acid pretreatment concentration of 0.05   M (corresponding to 4.28   wt.% sulfuric acid loading). For comparison, microcrystalline cellulose pretreated by 0.05   M sulfuric acid solution was pyrolyzed at temperature from 270   °C to 320   °C, and bagasse loaded with 3–5   wt.% phosphoric acid was pyrolyzed at temperature from 270   °C to 350   °C. The highest yield of LGO from bagasse was 30% higher than that from microcrystalline cellulose, and treatment with sulfuric acid allowed a 21% higher yield than treatment with phosphoric acid.