Optimizing Bioethanol Production from Elephant grass (Pennisetum purpureum) Using Lime-Buffered Fermentation and Gompertz Kinetic Modeling
نویسندگان
1 Department of Physics, Faculty of Science, University of Lagos, Lagos 101017, Nigeria
2 Department of Physics, Faculty of Science, University of Lagos, Lagos 101017, Nigeria
3 Department of Physical Science, School of Science, Yaba College of Technology, Lagos 101212, Nigeria
4 Department of Physics, Faculty of Science, University of Lagos, Lagos 101017, Nigeria
5 Department of Microbiology, Faculty of Science, University of Lagos, Lagos 101017, Nigeria
6 Department of Physics, Faculty of Science, University of Lagos, Lagos 101017, Nigeria
7 Department of Physics, Faculty of Science, University of Lagos, Lagos 101017, Nigeria
8 Biological and Analytical Application of Synthetic and Nanomaterials Research (BAASNMR) Group, Department of Chemical Sciences, Faculty of Science, Anchor University, Lagos 100278, Nigeria
9 Department of Chemistry, College of Science, Engineering, and Technology, University of South Africa, Florida Park 1709, South Africa
doi
10.30501/jree.2025.515054.2336چکیده
This study investigates the use of lime as a buffer solution to optimize pH and temperature for the fermentation of bioethanol from elephant grass (Pennisetum purpureum), a non-edible biomass. Bioethanol is an environmentally friendly alternative to fossil fuels, produced through the fermentation of starches, sugars, or cellulose. This study emphasizes the importance of controlling pH and temperature during fermentation, noting that enzymatic hydrolysis typically requires higher temperatures than fermentation. Samples of elephant grass were incubated at different pH levels (4.0, 4.5, 5.0, 5.5, and 6.0) and temperatures (25, 35, and 40 ℃) for one week. Following acid hydrolysis using lime—which also serves as a mildly acidic substance—as the nutrient medium, fermentation was conducted using baker’s yeast, selected for its cost-effectiveness and wide availability. The ethanol yields were measured and recorded using a digital refractometer. The results were analyzed using the Gompertz method to verify the accuracy of the experimental findings. The results showed that lime not only increased ethanol production efficiency but also affected the enzymes by maximizing yeast growth at temperatures above 30 ℃, specifically 35 ℃ in this study, with a total yield of 8 % (v/v) ethanol concentration and 12 % (v/v) ethanol concentration on the peak day (day 3) at a pH of 4. These findings indicate that temperature enhances ethanol concentration, whereas higher pH levels inhibit it.
