Abstract:
Esterification is an energy intensive and time consuming reaction. Establishment of equilibrium
and poor mass transfer reduces the overall conversion and rate of reaction. The current research
work is based on the microbubble mediated reactive distillation by converting conventional
homogeneous liquid-liquid system into a heterogeneous vapour-liquid system. Alcohol is
vaporized and fed in the form of microbubbles. The alcohol present in excess in a microbubble
reacts with acetic acid present at the interface, if the kinetics is controlled by surface reaction,
shifting the equilibrium in the forward direction. However, since alcohol is fed in the form of
bubbles over a period of time, excess alcohol does not exist in sufficient amount to establish
equilibrium in the reaction mixture. Microbubbles owing to their higher surface area to volume
ratio provides high mass transfer increase conversion and rate of reaction. To prove the
hypothesis, production of methyl acetate was investigated because of its industrial importance.
The experimental plan was designed using Response Surface Methodology. It allowed analyzing
the effects of operational parameters simultaneously. The kinetics investigation demonstrated
that the esterification reaction occurs, indeed, on the vapour liquid interface at the skin of the
bubble and follows pseudo-first order kinetics. Effect of Catalyst loading and molar ratio
between alcohol and carboxylic acid were found to be the significant on the conversion and
reaction rate. The maximum conversion of the process was found to be 91% in 20 min which is
significantly higher than any previous study
