Hydrolysis of corncob catalyzed by self-derived carbonaceous solid acid.

Carbonaceous solid acid (CSA) catalysts with –SO3H, –COOH, and phenolic –OH functional groups were prepared by hydrothermal carbonization and sulfuric acid impregnation methods. A maximum furfural (FF) yield of 19.66% from corncob degradation remained stable at 10 runs at 180°C for 170 min while the concentration of sulfuric acid was employed from 2.0 to 0.5 mol/L. The sulfur in CSA catalyst exists in two forms, namely SO42−and –SO3H. The free sulfuric acid and carbon together with –SO3H created good physical contact between the lignocellulose substrate and the solid catalyst in the reaction, and drastically improved the depolymerization rate of hemicelluloses and cellulose to soluble polysaccharide. [ABSTRACT FROM AUTHOR]