ABSTRACT

 Due to the rate at which the non-renewable energy sources such as fossil fuel are depleting worldwide and the attendant negative environmental impacts from its usage, Nigeria has joined the league of countries seeking for alternatives to fossil the!, which is currently the main income earner for the Country. Biofuel has emerged as a credible alternative and blend stock for the dwindling petroleum resources and also, Nigeria is committed to blending biodiesel with petro diesel up to 20%. Therefore, Production of biodiesel from dried avocado seed extract using transesterification method in which potassium hydroxide (KOH) is used as base catalyst was carried out in this study. ASTM standard fuel tests performed on the biodiesel extracted from the avocado seed extract gave promising results as alternative biodiesel. Concentrations of catalyst have been widely reported as an important process parameter upon which biodiesel yield depends. Thus in this work, the effect of KOH concentration on yield of the biodiesel produced from the dried avocado seed extract is studied, with a view of identifying the catalyst concentration corresponding to optimal process yield. Three replicated transesterification experimental runs were carried out for each of the KOH concentrations 0.5%, 0.75%, 1.0%,l.25%, 1.5%, 1.75% and 2.0% (by mass of avocado seed extract) under identical typical transesterification reaction conditions of 60°C temperature, 90 minutes duration and 20% ethanol (by mass of avocado seed extract). Results of the average yield of the biodiesel produced from the dried avocado seed extract for the respective catalyst concentrations are 92.50%, 94.50%, 95.80%, 84.60%, 73.65%, 70.90% and 71.15%. Also, physical properties such as viscosity, specific gravity, flash point, fire point, cloud point and pour point of the different biodiesel samples obtained from the seven experimental runs showed that KOH concentration had negligible effect on the quality of biodiesel produced. Therefore, KOH concentration of xl 10% resulting in maximum yield of 95.80% is recommended as optimum, within the constraint of the typical transesterification parameters used. These, findings agreeing well with earlier works will find useful applications in the energy sector of the Nigerian economy.