Water Hyacinth as Non-edible Source for Biofuel Production

Abstract

Water hyacinth (Eichhornia crassipes) represents a promising source for biofuel production and other bioactive compounds because of their high availability and high biomass yield. The present work aims to determine the possibility for biofuel production and other active compounds from seasonally collected water hyacinth. The water hyacinth samples were collected at four seasons (2014/2015) from River Nile, Giza, Egypt, and the biofuel (biodiesel and bioethanol), lipids, glycerol content, carbohydrates and other biochemical compounds were determined in addition to physico-chemically characterized of produced biodiesel The obtained results indicated that, water hyacinth samples showed variable lipid contents (6.79–10.45%), which by transesterification produced biodiesels (3.22–6.36%) and sediment (pigments+glycerol). Biodiesel composed either totally of saturated fatty acids (Myristic acid) of winter and autumn samples, However, Myristic and Stearic acids with small proportion of pentadecanoic acid of summer and spring samples by 8.1 and 7.9% respectively. The monounsaturated fatty acid, Oleic, was only recorded in the summer sample by11.6%. So biodiesels produced from water hyacinth have good stability and acceptability to be used in diesel engines, the co-products (sediment) composed of pigments and glycerol reached to 4.69 mg/g and 1.05 mmol/L respectively in winter season. Also, pretreatment of water hyacinth by acid at mild conditions was found to be effective with high yield of fermentable sugars and production of ethanol during 120–180 min for different seasonally collected plants. From the results, we can conclude that the produced biodiesel (from water hyacinth) was within the recommended standards and met the criteria required to be a diesel substitute compared with the Egyptian fuel standards In addition, it is possible to use its pigments as natural coloring substances in food industry, and glycerol can be incorporated in different petrochemical industries.