Hydrolysis of Sorghum (Broomcorn) in Diluted Hydrochloric Acid

Effective conversion of lignocellulosic material as renewable energy source has significant reflection on economic and environmental impact. Diluted acid hydrolysis at optimal condition was used to liberate fermentable sugar. The sorghum stalks, the alkali pretreatment of biomass and hydrolysis in diluted hydrochloric acid were investigated. The hydrolysis reaction was carried out in a 5L reactor. Several process parameters such as reaction temperature (35to 75°C), acid concentration (3to 7% (w/w)) and dry solid material content (3to 7% (w/w)) were studied. The results showed that the optimal reaction conditions were defined at 75°C, acid concentration of 7% and dry solid material content 5% (dry solid). Under the optimal conditions, maximum reducing sugar yield of about 39% (g/g dry solid) was obtained. SEM and FTIR analysis of the solid residues confirmed disruption of the biomass texture and removal of functional groups associated with cellulosic fibers.