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The quest for renewable and sustainable energy generation is fast becoming widespread across Africa due to the understanding that there is a need to seek an alternative to fuels of fossil origin, which currently sustains the largest portion of the world's energy need. Research into the generation of renewable fuels had been on-going in continents like Europe, South America, Asia, and other developed countries bearing in mind the extinction nature of fossil fuels. Globally, attentions are being drawn to fuel generation from biomass and its derivatives such as lignin, triglycerides, cellulose, and hemicelluloses. The aim is to use such fuels for cooking and heating and in vehicles, jet engines, and other applications. Therefore, the integration of the African continent in the race for biofuel production is germane in the quest for survival and developments considering favorable factors like climate, soil, and land mass among other environmental-friendly resources in different African countries.

Background:Napier grass is a naturally abundant waste material that can be cultivated over a vast area of land which makes it a viable source for sugar and bioethanol production.Introduction:The presence of lignin in the biomass makes cellulose inaccessible for conversion to useful products, however, in order to provide for efficient utilization of the waste material, reagent and energy, a study on the kinetics of lignin removal from Napier grass was carried out in this work using 1 and 3 w/w % NaOH at temperatures between 80 and 120°C.Materials & Methods:Based on the investigation, there was increased lignin removal for increased NaOH concentration. Kinetic parameters were also determined and it was observed that, the reaction of lignin in Napier grass with NaOH obeys a pseudo-zero or pseudo-fractional order kinetics. Furthermore, the orders of the reaction for the pretreatment conditions of 3 w/w% NaOH at 100°C and those of 3 and 1 w/w NaOH at 120°C gave close reaction orders of 0.2, 0.22 and 0.24 respectively after 110 minutes, which implies that, for the three cases, the residual lignin in the extract was almost the same at the pretreatment conditions while slight differences are evident in their pseudo rate constants. Also, it was observed that, the activation energy of the reaction reduced significantly as the concentration of NaOH increased from 1w/w - 3 w/w%.Conclusion:Based on the AIL and the total lignin (i.e.AIL + ASL) in the Napier grass, the recorded delignification efficiencies at the optimum pretreatment time of 17.5 h are 90 and 76% respectively. In addition, the adopted Differential Technique (DT) combined with the Ostwald Method of Isolation (OMI) can be accurately used to study the kinetics of lignin removal from Napier grass.