Ethanol production from water hyacinth (eichhornia crassipes) using various types of enhancers based on the consumable sugars

Ethanol production from cellulosic biomass could effectively increase using enhancers. In this study, five types of different enhancers: fermented malt extract (FME), fermented barley extract (FBE), Saccharomyces cerevisiae (SC), horse dung (HD) and mixture of all enhancers (Mix) were used in order to evaluate the sugar and ethanol production from water hyacinth. Acid pretreatment (H2SO4) was used in order to enhance digestibility for conversion of water hyacinth into ethanol. To observe the efficiency of pretreatment SEM and FTIR was used to observe the structural changes of water hyacinth before and after pretreatment. The sugar consumption rate was in order of MIX, SC, HD, FME and FBE during 60 h fermentation time, respectively. The highest ethanol produced by MIX with 5.1 ± 1.2 g/L with 60% sugar consumption, 0.085 gp/L/h ethanol volumetric productivity, 0.42 gp/gs ethanol yield and 82% theoretical yield in 60 h of fermentation. Ethanol production followed up by 3.4 ± 0.8, 3.2 ± 0.9, 1.5 ± 0.4 and 1.1 ± 0.5 g/L using SC, HD, FME and FBE, respectively. The results shows that ethanol production rate is correlated to sugar consumption during fermentation