Harnessing the potential of bio-ethanol production from lignocellulosic biomass in Nigeria - a review

The need to diversify energy sources and to change from the present non-renewable hydrocarbon sources to renewable energy sources has prompted huge investments in research activities to produce bioethanol from carbohydrate-rich foodstuffs such as cassava tuber, sugarcane molasses, yam tubers, rice grains, corn grains, and a host of others. In recent times, however, more attention has been given to producing bioethanol from the non-edible parts of carbohydrate-rich foodstuffs, which are obtained mainly as waste products from food-crop processing. Such non-edible components include peels, bagasse, straw, stalk, and cobs. The most important component of the biomass is lignocellulose, which is broken down into carbohydrates and then fermented. The major challenge in deploying biomass as feedstock for bioethanol production is the fact that lignocellulosic biomass is highly recalcitrant and therefore requires more vigorous pretreatment prior to saccharification and fermentation. The main techniques used for pretreating lignocellulosic materials are physical and thermal as well as chemical and biological methods. In Nigeria, lignocellulosic bioethanol production potential from agricultural residues amounts to about 7.556 x 10(9) L per annum with more than 62% generated from process residues. Cassava biomass alone can produce more than 114 L of bioethanol for every ton of cassava peels after processing. Nigeria has more than enough agricultural residues for bioethanol production to meet its sustainable bioethanol-blending demands. (c) 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.