Orthogonal array design for biodiesel production optimization: using ultrasonic-assisted transestification of Camelina sativa L. Crantz oil

Abstract

Camelina seed oil has recently attracted great interest as a low-cost feedstock for biodiesel production because of its high oil content and environmental benefits. In the present study, an orthogonal array design was used to optimize the biodiesel production from camelina seed oil using ultrasonic-assisted transesterification. Four relevant factors are investigated: methanol to oil ratio, catalyst concentration, reaction time and temperature to obtain maximum fatty acid methyl ester (FAME) yield of biodiesel. An OA25 matrix was employed to study the effect of the four factors, by which the effect of each factor was estimated using statistical analysis. Based on the results of the statistical analysis after the orthogonal experiments, maximal biodiesel FAME yield (98.6 %) was obtained under the conditions of 8:1 methanol to oil molar ratio, 1.25 wt.% catalyst concentration (KOH), 50 min reaction time, and 55 ℃ reaction temperature. Other properties of the optimized biodiesel, including density, kinematic viscosity, and acid value, were conformed to the relevant ASTM and EN biodiesel standards and thus the optimized biodiesel from camelina oil basically qualified to be used as diesel fuel.