Experimental study on evaluation and optimization of conversion of waste chicken fat into biodiesel

Full text: This study was initiated to evaluate and optimize the conversion of waste chicken fat (WCF) into ethyl and methyl ester called biodiesel. The physical and chemical characteristics of these esters were much closer to those of Diesel fuel than those of fresh vegetable oil or fat, which makes them a good substitute for Diesel fuel. Experiments have been performed to determine the optimum conditions for this conversion process using a three factor factorial design for producing biodiesel. The major variables in the transesterification process are determined from the pre experiments as: reaction temperature, molar ratio of alcohol/oil, alcohol type utilized and catalyst type. Absolute ethanol was found better than absolute methanol, since ethanol gives higher conversion and less viscosity at all levels, mainly at 100% excess concentration. Temperature had no detectable effect on the ultimate conversion ratio and viscosity for both ester products. However, higher temperatures decreases the time required to reach maximum conversion, which will be at the expense of the cost of energy. An interaction between time and temperature was found for all conversions. Therefore, 60 C was found to be the optimum temperature, and one hour is the optimum time for the conversion of WAFs into biodiesel. The obtained product with 97.02% of biodiesel was analyzed and characterized by gas chromatography. (author)