Determination of mass transfer of non-water soluble substrates, as hexadecane (HXD), is an important constraint in three-phase airlift bioreactor. A new simple dynamic technique able to measure the hexadecane transfer rate (HTR) in a three-phase airlift bioreactor (ALB) was studied in this work. The image analyses technique allowed measuring the resulting specific mass transfer area (aHXD). Gas chromatography was used to measure time-dependent transferred HXD and therefore the HXD transfer coefficient (kLHXD). Finally, HTR was calculated by using the equation HTR = kLaHXD(CHXD* - CHXD) where CHXD* and CHXD are the saturation HXD-aqueous interphase and HXD aqueous phase concentration, respectively. As case study, we successfully applied to the measurement of HTR during a typical ALB microbial consortium culture; values from 0.010 to 0.042 mg HXD (L h)-1 were found. This technique could be used to compare similar simultaneously occurring parameters to assess mass transfer constraints in three-phase systems.
©2012 Walter de Gruyter GmbH & Co. KG, Berlin/Boston