Effects of headspace pressure on hydrogen production by photosynthetic bacteria

The experiment is focused on the influence of headspace pressure on H₂ production, which is produced by mixed photosynthetic bacteria, whose substrate is glucose. The inoculum´s concentration are 10%, 20%, 30%, 40%, 50% respectively, meanwhile, headspace pressure are at levels of 0.001MPa, 0.000MPa, -0.001MPa, -0.002MPa, -0.003MPa, -0.004MPa, -0.005MPa. It comes to the conclusion that delay time of H₂ production is shortened, at the same time, H₂ production velocity and the output of H₂ production are increased with the reduction of headspace pressure. It is obvious that production time is shortened, efficiency and output of H₂ production are improved by headspace pressure reduction, which makes the H₂, and CO₂ pressure decrease, thus solubility is dropped, therefore, feedback inhibition is removed or weakened.