ASABE Technical Library - Abstract

Abstract. The imminent and unavoidable exhaustion of global reserves of fossil fuels continues to elicit scientific investigations into practical options which the world can exploit to provide energy. Scores of biological organisms which can be used as substrates for biofuel production have been identified around the world. Those used for food present a risk to food supply, and this necessitates investigating the energy potential of non-food biomass. This work reports on investigations carried out on Iroko timber as a substrate for bio-ethanol production. Iroko (Chlorophora excelsa) is a sturdy tropical hardwood abundantly grown in the African tropics primarily to supply timber used in furniture making, tool manufacture and building construction. Four replicates each of 5, 15, 25, and 35kg of converted Iroko timber at 15% moisture content were digested in the laboratory following standard procedures. The average masses of ethanol extracted for each of these selected masses were 0.51, 1.54, 2.57 and 3.6kg respectively. Corresponding volumes of ethanol measured were 0.65, 1.95, 3.25 and 4.55 litres respectively. The average ethanol production rate measured for all samples is 0.13L/kg (i.e 130L/tonne) of wood. Comparing this value to 410, 100, 139, 150 and 70L/tonne of material earlier reported for maize, carrot, cocoyam, cassava, and sugarcane; all promising food crops under investigation as bio-ethanol substrates, it is seen that Iroko timber also has a good potential as a future energy crop for bio-ethanol production.