Investigation and Scaling of Hydrogen Production by Klebsiella sp. ABZ11 for Optimal Yield and the Kinetics of Batch Fermentation Process

Abstract

The slow metabolism of bacteria at low temperatures affects the catalytic efficiency of enzymes and productivity. This article investigates the use of a psychrotolerant bacteria (Klebsiella sp. ABZ11) for biohydrogen production, yield and scaling at optimal temperature, pH and glucose in a batch fermentation process within a 2-liter bioreactor using Response Surface Methodology (RSM) to report the process performance. The results show 33.5°C, pH 6.75 and 9.15 g glucose as the optimal conditions. Scale-up yielded 137.56 mol/L biohydrogen, 22.13% more than production under optimized conditions. Biomass grew at 0.081/h and doubled in 17 h with 0.71 g cells to reach maximum production. Compared to 0.062/h, 22 h with 0.87 g cells in optimal condition to achieve maximum biohydrogen production. This result shows the potential of biohydrogen production using Antarctic psychrotolerant bacteria at mesophilic temperature.