Production of Biodiesel from Desert Date Seed Oil Using Heterogeneous Catalysts

Abstract

In the recent time, there is increasing research in the area of alternative fuels as the exhausts of presently used petroleum-based fuels have been identified to have negative effects on the environment. Fuels produced from plant oils and animal fats have the tendencies of replacing petro fuels since they are renewable in nature. One of these renewable fuels is biodiesel. However, the homogenous catalyst used in biodiesel production has some drawbacks such as difficulty in separation from the fuel, soap formation and corrosiveness of the product mixture. In this work, the use of heterogeneous catalyst sourced from local raw materials (kaolin and eggshell) for the production of biodiesel from oil of desert date seed has been investigated. The kaolin obtained from Alkaleri Mining Site, Bauchi, was calcined in an oven at 800 °C for 3 h. The calcined kaolin was then chemically activated. Also, the eggshell-based catalyst was produced from raw eggshells after washing, drying, grinding, sieving using 0.3 mm sieve size and calcining at 900 °C for 3 h. Furthermore, the oil content of the desert date seed, which was acquired from a local market in Bauchi, was extracted via solvent extraction in a laboratory with a yield of 42%. Then, the biodiesel was subsequently prepared by mixing the oil, methanol and catalyst in a flat bottom flask and heating the mixture for a specified period. The catalyst concentration, methanol to oil ratio and time of reaction were subsequently varied to obtain the best yield. The results obtained revealed that an optimum yield of 29% could be obtained at methanol to oil ratio of 6:1 and a reaction time of 60 min using 1.5 g of eggshell-based catalyst while an optimum yield of 22% was obtained with 0.6 g for kaolin-based catalyst at a reaction time of 60 min and methanol to oil ratio of 4:1. It is recommended that further work should be carried out to improve on the yield of the biodiesel obtained using the heterogeneous catalysts.