Abstract：The response surface methodology (RSM) was used to optimize the hydrolysis reaction conditions of rhamnolipids for preparation of rhamnose. On the basis of single factor experiments, three-factor response surface analysis method was used to study the hydrolysis yield of rhamnolipid in the hydrolysis process using the amount of sulfuric acid, reaction temperature, and reaction time as three-levels according to the Box-Behnken central combination design principle. The regression equation between the hydrolysis yield and three factors was fitted to optimize the hydrolysis reaction conditions of rhamnolipids. The results showed that the amount of sulfuric acid and the reaction temperature had significant effect on the hydrolysis of rhamnolipid. The interaction between the amount of sulfuric acid and hydrolysis time, and the interaction between hydrolysis temperature and time both have significant effects. The quadratic effects of various factors were extremely significant. The optimal hydrolysis conditions derived from the model were: 2.3% (mass fraction) of sulfuric acid, hydrolysis temperature of 137 ?C and the hydrolysis time of 2.8 h. Under these conditions, the actual yield of rhamnose was 81.6%, which was in agreement with the predicted value of 82.35%. Finally, the model was futher applied to 3 m3 industrial-scale hydrolysis production and the prediction error was found to be in between -8.12% and 9.30%, indicating that the model had a good reference value for industrial production.
