Optimization of Production Variables of Biodiesel from Manketti Using Response Surface Methodology

Abstract

Manketti oil that was used as a feedstock to produce the biodiesel was extracted from manketti nut. An alkali catalyst transesterfication process was adopted. A statistical model was developed to correlate the transesterification process variables to the yield of fatty acid methyl ester (FAME) using a central composite design (CCD) by a response surface methodology. The transesterification process variables were reaction temperature x₁, (30°C–65°C), amount of catalyst x₂, (0.5–1.5 wt%), amount of methanol in the oil x₃, (10–50 wt%), and reaction time (30–90 min). The essential fuel properties such as density, flash point, viscosity, and acid number were measured and compared with other types of biodiesel produced from wild nuts and American Society for Testing and Material (ASTM) standards for biodiesel. From the results, the optimum conditions for the production of FAME obtained were as follows: reaction temperature 55°C, reaction time 53 min, amount of catalyst 1.02 wt%, and amount of methanol in the oil of 32 wt%. The optimum yield of FAME that can be produced was 98.3%. The results show that the important fuel properties of the biodiesel produced in optimum conditions met the biodiesel ASTM standard.

Keywords:

• Manketti
• Fatty acid methyl ester
• Fuel properties
• Response surface methodology