Regime analysis of a Baeyer–Villiger bioconversion in a three-phase (air–water–ionic liquid) stirred tank bioreactor

The aim of this work was to conduct a regime analysis on a three-phase (air–water–ionic liquid) stirred tank bioreactor of the Baeyer–Villiger bioconversion process, using [MeBuPyrr][BTA] ionic liquid as the dispersed phase. The regime analysis based on characteristic times of the different mechanisms involved (mixing, mass transfer, reaction) can yield a quantitative estimate of bioreactor performance. The characteristic time obtained for oxygen uptake rate (54 s−1) was among the characteristic times determined for oxygen transfer (13–129 s−1) under different operating conditions, suggesting that the oxygen transfer rate under certain operating conditions could be a limiting step in the bioconversion process. Further enhancement of oxygen transfer rates requires proper selection of the bioreactor operational conditions, and improved design of the ionic liquid used as oxygen transfer vector.

► We conduct a regime analysis on a three-phase stirred tank bioreactor.
► We studied a bioconversion process using [MeBuPyrr][BTA] as the dispersed phase.
► Regime analysis was based on characteristic times of different mechanisms involved.
► Oxygen transfer rate under certain operating conditions could be a limiting step.