Optimisation of acid hydrolysis in ethanol production from Ampelodesmos mauritanicus (Diss)

In this work, statistical modeling and optimization of hydrolyzate from Ampelodesmos mauritanicus (Diss) using 1.5% sulfuric acid hydrolysis was carried. A central composite design (CCD) model was used to study the influence of reaction temperature (70°C to 110°C), ratio (5% to 15%, w/v), and reaction time (60 to 180 min). Reducing sugars, pH, proteins, lignin, ash content and the elements minerals composition were determined. Optimized reducing sugars yield of 0.249 g.g-1 of dry weight was obtained for reaction time of 180 min, reaction temperature of 110°C and ratio 5% (w/v). Therefore, this study tests the production of bioethanol from pure Diss hydrolyzate by the yeast Saccharomyces cerevisiae ATCC 9763. This strain showed a consumption of 67.6% of reducing sugars available (25 g.L-1), which made it possible to obtain ethanol yield per consumed sugar 0.33 g.g-1.