Dynamic Model For Production of Biohydrogen Via Water- Gas Shift Reaction (RESEARCH NOTE)

In design of anaerobic bioreactor, rate equation is commonly used. Mathematical model was developed at steady state condition, to project concentration of gaseous substrate and product in biological oxidation of carbon monoxide with water to produce hydrogen and carbon dioxide. The concept of bioconversion was based on transport of CO from gas phase to liquid phase, as the CO consumption was instantaneous and the moles of CO in liquid phase was oxidized to CO۲, and H۲ was liberated from water. The moles of produced H۲ were identical to the moles of CO transported to the fermentation media. The data was experimentally obtained in a continuous stirred tank bioreactor. A photosynthetic bacterium, Rhodospirillum rubrum, was used as biocatalyst to facilitate the oxidization of carbon monoxides via water-gas shift reaction. The rate of CO consumption and hydrogen production were projected based on dynamic model at steady state condition. The experimental data were fitted to a few rate models and the best suitable dynamic model for hydrogen production was obtained. The model was used for scale up calculation and dependency of the rate equation and the model to a few process variables were analyzed. The liquid phase medium was supplied for microbial growth with initial concentration of ۴. The media flow rate to the reactor space time (F/VL) was ۰.۲ h-۱. At the steady state condition, the concentration of acetate was independent of the dilution rate and it was approximated about ۱.۵ g/l.

Keywords:

CO transport Model , Steady State Mass Transfer , Continuous Bioreactor , Photosynthetic Bacteria , hydrogen , Rhodospirillum rubrum