Effect of Alkali Preteatment on Water Hyacinth Biomass for Production of Ethanol

The current crisis of fosile fuels, a non-renewable resource, has become a serious issue to be taken care of in our modern world. Bioethanol from lignocellulosic biomass is a potential alternative to the conventional fossil fuels. The structural and chemical complexity of the biomass provides a significant hindrance to the production of bio-ethanol. However, various chemical and biological pretreatment methods can break the complex structure of the biomass to produce various sugar derivatives. They are further treated by enzymatic methods to increase the yield of reducing sugars significantly, and finally fermented with the help of microorganisms to produce bioethanol. In enzymatic saccharification process, maximum yield for reducing sugars was 465 mg/g and xylose was 231 mg/g using commercial enzymes cellulase and xylanase. Ethanol production is maximum with Pichia stipitis (4.13 gm/L) as compared to Candida shehatae (3.79 gm/L) and Saccharomyces cerevisiae (3.07 gm/L). This paper emphasizes the importance of water hyacinth in the production of bioethanol and the effect of alkali pretreatment method on the biomass and the future scope.