การเปรียบเทียบการผลิตไบโอบิวทานอลจากฝักจามจุรีและราชพฤกษ์

Abstract

The production of bioenergy from renewable resources is a promising solution to energy issues as well as the associated environmental problems. For bioenergy production, lignocellulosic biomass is widely considered as a sustainable feedstock because it is inexpensive, highly abundant and broadly distributed. In this thesis, biobutanol production by biological fermentation was studied analyzing the feasibility and thermal extraction method of rain tree and golden rain tree pods for biobutanol production by Clostridium acetobutylicum TISTR 2375. Rain tree and golden rain tree pods were extracted by thermal extraction method using 30, 63 and 96 °C at 20, 40 and 60 min. Furthermore, the Response Surface Methodology (RSM) was used based on Central Composite Design (CCD) in order to evaluate and optimize the effect of temperature and time as an independent variable on the total sugar and reducing sugar concentration. The interaction effects and optimal parameters were obtained using Design Expert 11.1.0 software (Stat-Ease Inc., Minneapolis, USA). The results showed that the optimal condition of thermal extraction in the amount of total sugar and reducing sugar was at 63 °C for 40 min (rain tree pods) and 96 °C for 60 min (golden rain tree pods). Both variables have a significant effect on the total sugar and reducing sugar concentration. After which, the raw materials that were thermally extracted at the optimal condition were enzymatic hydrolyzed with 2% (v/v) cellulase enzyme at a temperature of 50 °C for 24 hours. The enzymatic hydrolysis found that the rain tree pods have the efficiency of hydrolysis of 51% and golden rain tree pods have the efficiency of hydrolysis of 41%. The production of biobutanol by Clostridium acetobutylicum TISTR 2375 from rain tree and golden rain tree pods that have been enzymatic hydrolyzed diluted approximately 80 g/L of reducing sugar. The results showed that rain tree pods could produce biobutanol concentration of 1.1718 g/L and golden rain tree pods could produce biobutanol concentration of 0.0628 g/L. Henceforth rain tree pod produced a higher biobutanol yield than golden rain tree pods. Rain tree and golden rain tree pods may contain inhibitors for cell growth that results in low biobutanol. Therefore, these two plants should be further studied to increase the efficiency of biobutanol production. However, rain tree and golden rain tree pods are interesting new feedstock that can potentially reduce the cost of energy and enzyme inputs currently used in the conventional biomass-to-biofuel processes.