Optimization of pretreatment condition for ethanol production from Cyperus difformis by response surface methodology

This study investigated the potential of a new material, so-called small-flowered nutsedge, for bioethanol production. This plant causes the huge loss of rice yield as it competes nutrients, sunlight and other necessary elements with rice plant to grow. The project plans to transform its biomass into valuable product and bring profitable for famers. The powered raw sample was treated with sodium hydroxide (NaOH) and hydrogen peroxide (H₂O₂) as followed the design experiment. The use of response surface method is helping researcher to save time and effort but still gain meaningful predicted value that closed to the actual value. The highest total sugar was given when the pretreatment condition is solid to liquid ratio of 0.05, 1% NaOH, 1% H₂O₂ for 72 h. The efficiency of hydrolysis can reach 47% after 24 h with cellulase enzyme at 50 °C, 150 rpm and highest ethanol concentration was obtained on the fifth day of fermentation.