Measurement and prediction of mass transfer coefficients for syngas constituents in a hollow fiber reactor.

Syngas fermentation for producing biofuels and other products suffers from mass transfer limitations due to low CO and H2 solubility in liquid medium. Therefore, it is critical to characterize mass transfer rates of these gases to guide bioreactor design and optimization. This work presents a novel technique to measure the volumetric mass transfer coefficients (kia) for H2 and CO using gas chromatography in a non-porous hollow fiber reactor (HFR). The largest measured kia for H2 and CO were 840 and 420 h-1, respectively. A model was developed to predict kia for H2 and CO that agreed well with experimental data. This study is the first to measure, compare, and model both H2 and CO mass transfer coefficients in an HFR. Based on model predictions, HFRs have the potential to be a reactor of choice for syngas fermentation as a result of high mass transfer that can support high cell densities.