• Sri Purnama Sari, Armansyah H Tambunan, dan Lilik P EkoNugroho


Current technology for biodiesel production is a transesterification process of vegetable oil with
metanol in batch system with the help of catalyst. The technology faces many disadvantageous for large scale,
such as the requirement for rigorous stirring and purification of the product from the catalyst. Previous study
showed that utilization of static mixing reactor can enhance the reaction rate and reduce the requirement of
catalyst and can be operated continuously. The objective of this study was to examine the role of static mixer in
reducing the catalyst requirement for the transesterification process of biodiesel production in continuous mode.
Palm oleinwas used as feedstock for the transesterification process with 1:6 of mole ratio to metanol at 65oC
reaction temperature. Catalyst used for the experiment was KOH with variations of 0.3% and 0.5% to the oil fed
into the reactor and the numbers of static mixer modules were varied (1, 2, 3, 4, and 5 modules) to evaluate their
effects to the required catalyst. As expected, the experimental results confirmed a higher conversion of the
reactionby the increasing number of the static mixer modules at a specific catalyst percentage. Highest
conversions obtained with 5 moduleswere 92.5% (w/w) and 88.9% (w/w), for 0.3% and 0.5% of catalyst,
respectively. Analysis to the experimental results showed that 0.1% of catalyst could be replaced by the addition
of 0.9 modules of static mixer, which was equivalent to 58.1 cm length ofthe used static mixer configuration.
Keywords:continuous mode of transesterification, static mixing module, catalyst reduction