Optimal design in biodiesel production from esterification of palmitic acid in excess methanol

Optimization of esterification of palmitic acid in excess methanol by solid acid catalyst, viz. Amberlite? IR-120 (H) resin, is studied by combining backward stepwise regression technique with a 2 5-1 fractional factorial design. Optimum conditions are found as follows: 8:1 in the molar feed ratio of methanol to palmitic acid, a reaction temperature as 61.0 ¢XC, a reaction time of 10.5 h, catalyst loadings at 10 wt% of palmitic acid, and a stirring speed of 600 rpm. At this condition, conversion efficiency of palmitic acid to palmitic acid methyl ester reaction is near 98.9%.