Evaluation of pretreatment techniques in water hyacinth (Eichhornia crassipes) for the production of bioethanol

Abstract

Water Hyacynth (Eichhornia crassipes) is a fast growing aquatic plant that represents a serious problem of invasion, so its transformation into ethanol is proposed as a solution, taking into account the imminent scarcity of fossil fuels worldwide and the panorama of opportunity that is lived in the world due to the legislation on biofuels. For this, four different pretreatments were evaluated taking into account production of sugars and final ethanol yield to select the most promising. In this preliminary selection, the Water Hyacinth exhibited chemical type compositional characteristics that make it a promising raw material for ethanol production, obtaining yields of 17.15 g/l, 18.10 g/l, 17.73 g/l and 4,53 g/l with the pretreatments aqueous ammonia soaking, alkaline delignification, pretreatment with diluted acid and alkaline peroxide, respectively. Finally, the pretreatments with diluted acid and alkaline delignification were selected to be studied more deeply through the application of an experimental design, obtaining an ethanol yield (better design conditions). 190.35 l/ton dry biomass fed to the diluted acid pretreatment and 197.33 l/ton dry biomass fed to the alkaline delignification pretreatment, from the solid fraction.