Abstract:
The compatibility of the surfactants with lipase ZG, used for biodiesel synthesis was investigated , and the surfactants with a strong activating effect on lipase ZG, such as LAS, Peregal O and OP-10 were selected for compounding. The activation concentrations of the above surfactants were 3 g/L, 3 g/L, and 6 g/L respectively. The optimal activation concentrations were 6 g/L OP-10, 3.5 g/L LAS, and 4.5 g/L Peregal O, which were optimizated by response surface method. Under optimal conditions, the lipase activity was 34 454 U/mL, while the predicted value was 34 000 U/mL and there was a little difference between the predicted value and the experimental value. Further optimization experiment was performed by diluting 7 times of the lipase ZG and then compounded with the surfactants. The result showed that the lipase activity increased from 28 000 U/mL to 35 560 U/mL, increased by 27%, and the cost decreased by 85.6%. The degreasing experiments indicated that when the dosage of the compound lipase Es is half of the chemical degreasing agent, the degreasing ratio of the compound lipase Es is 70.26%, which is 3.78% higher than that of chemical degreasing. In addition, compared with the chemical degreasing agent, the dosage of surfactants in the compound lipase Es decreased by 99.3%, and the application cost shorted about 32.67%. Thus, the compound of lipase ZG with surfactants is effective.