Effect of zinc ion on photo-fermentative hydrogen production performance, kinetics and electronic distribution in biohydrogen production by HAU-M1

The aim of this work was to study the characteristics, kinetics and electronic distribution of photo-fermentation hydrogen production (PFHP) with Zn2+ addition then gave the main results that the addition of Zn2+ can effectively improve hydrogen production with an increasing of 1-5 mg/L Zn2+ concentration. The maximum hydrogen yield of 592 +/- 13 mL and shortest lag time of 4.67 h were obtained at 2 mg/L Zn2+. 26.42% of the substrate energy was diverted to H-2. Modified Gompertz and Hane-Levenspiel models were applied to evaluate the effect of Zn2+ on PFHP by mixed bacteria HAU-M1, the constants n and m obtained by fitting models were 14.97 and 58.79, respectively, indicating the fermentation system was noncompetitive inhibition, the predicted critical Zn2+ concentration was 40.83 mg/L.

Automated summary

The study found that the addition of Zn2+ can significantly improve the efficiency of photo-fermentation hydrogen production, and it exhibits noncompetitive inhibition. Through modeling predictions, the optimal Zn2+ addition concentration was determined to be 40.83 mg/L.