Production of fermentable sugars from Chlorella sp. by solid-acid catalyst

Abstract

The hydrolysis of microalgae Chlorella sp. via a solid acid catalyst was conducted in order to obtain fermentable sugars. To optimize the hydrolysis conditions, Box-Behnken design was used to construct the experimental setup. Results show that the highest fermentable sugar yield of 50.4% (25.2 g/L) was achieved using a reaction composed of 5% biomass and 40% solid acid catalyst loading (based on biomass), at a reaction temperature of 160 °C for 45 min. Moreover, under these conditions, only 1.16 g/L of 5-HMF and 0.12 g/L of levulinic acid were formed as by-products. Furthermore, at 12.5% biomass concentration, a 56.97 g/L (45.58%) high concentration of fermentable sugars was obtained. In conclusion, the utilization of microalgae and a solid acid catalyst for fermentable sugar production has a high possibility of applicability.