Enzymatic kinetics of cetyl palmitate synthesis in a solvent-free system

Cetyl palmitate was synthetized by esterification the cetyl alcohol with palmitic acid in a solvent-free system. Reactions were performed in batch mode using commercial lipase Lipozyme RM IM as catalyst. Stirring speed (180, 480 and 720 rpm), temperature (60, 70, 80 and 87 degrees C), amount of catalyst (0.5, 1.0 and 1.5% wt% related to the mass of substrates) and alcohol:acid molar ratio (0.5:1,1:1 and 2:1) were evaluated and best reaction conditions obtained were 480 rpm, 70 degrees C, 1.0% of enzyme and 1:1 M ratio. A novel kinetic model based on random-sequential bi-bi mechanism was proposed and showed a good agreement with experimental data. Furthermore, this model was proved to be suitable for kinetics predictions with a small uncertainty. The catalyst was recycled and showed good stability since reaction conversion decreased only 6.8% after 15 reuses. (C) 2018 Elsevier B.V. All rights reserved.