Comparison of static-mixer and blade agitator reactor in biodiesel production
Abstract
One of the difficulties faced in the current technology for biodiesel production is the requirement for rigorous mixing of methanol with the feedstock oil in the reactor. Utilization of blade mixer is limited by the immiscible state of those substances. This research is devoted to the assessment of static-mixer utilization in a transesterification reactor for biodiesel production in terms of kinetics reaction (reaction rate coefficient k, activation energy Ea, and collision factor or coefficient factor A). The experiments were conducted by reacting palm oil (triglyceride or TG) with methanol (MeOH) at 50, 55, 60, 65, and 70℃, using potassium hydroxide (KOH) as catalyst. Molar ratio of TG and MeOH was 1 : 10.5 and KOH used was 1% of palm oil weight. Transesterification process using blade agitator with the same reaction condition was performed as base of comparison to those of static-mixer. The experiments showed that static-mixer has significant effect in reducing reaction time to reach required fatty acid methyl ester content (FAME) i.e. 96.5% than those of blade agitator. Transesterification reaction time with static-mixer is shorter than with blade agitator for all temperature levels. Reaction temperature of 65℃ with five minutes of reaction time is demonstrated the best condition for running the static-mixer reactor. The static-mixer and blade agitator experiments exhibited two stages transesterification that give the initial and the final activation energy (Ea1 and Ea2) and the initial and final collision factor (A1 and A2). The value of Ea1, Ea2, A1, A2 for static-mixer experiments is 0.13 J/mol, 37.1 J/mol, 4.8, and 1,256, respectively. Meanwhile the value of Ea1, Ea2, A1, and A2 for blade agitator experiments is 0.81 J/mol, 6.9 J/mol, 2.0 and 11.8, respectively.
Keywords: static mixer, blade agitator, activation energy, utilization, biodiesel, collision factor, transesterification.
Citation: Alamsyah, R., A. H. Tambunan, Y. Aris Purwanto, and D. Kusdiana. Comparison of static-mixer and blade agitator reactor in biodiesel production. Agric Eng Int: CIGR Journal. 2010, 12(1): 99-106.
