This study evaluated the impact of three different iron compounds (Fe₂O₃, FeSO₄, FeCl₃) on hydrogen production via mesophilic dark fermentation (DF) of hydrolyzed sugar beet pulp (SBP). In batch tests, the maximum hydrogen yield of over 200 dm³H₂/kgVS was achieved with the addition of 0.1 gFe₂O₃/dm³, which was twice greater than the control. In semi-continuous experiments, the highest hydrogen production of 52.11 dm³H₂/kgVS combined with 19.4 dm³CH₄/kgVS methane yield was obtained at a dose of 1 gFe₂O₃/dm³. Acetic, lactic and caproic acids were the main metabolic products of DF. Microbiological studies showed some balance between hydrogen producing microorganisms from the order Clostridiales and lactic acid producers (LAB) affiliated with the orders Lactobacillales and Coriobacteriales. Moreover, the presence of methanogens affiliated to the genera Methanobrevibacter and Methanosphaera was also documented. An interesting finding was the appearance of rare bacteria from the genus Caproiciproducens, which was responsible for increased caproic acid production.

这项研究评估了三种不同的铁化合物（Fe ₂ O ₃，FeSO ₄，FeCl ₃）对水解甜菜粕（SBP）的中温暗发酵（DF）产生氢的影响。在分批测试中，通过添加0.1 gFe ₂ O ₃ / dm ³达到了200 dm ³ H ₂ / kgVS的最大氢产率，是对照的两倍。在半连续实验中，在剂量为1 gFe的条件下，最高产氢量为52.11 dm ³ H ₂ / kgVS，结合19.4 dm ³ CH ₄ / kgVS的甲烷产率₂ O ₃ / dm ³。乙酸，乳酸和己酸是DF的主要代谢产物。微生物学研究表明，梭状芽胞杆菌属的产氢微生物与乳酸杆菌和肠杆菌属的乳酸生产者（LAB）之间存在一定的平衡。此外，也记录了属于甲烷短杆菌属和甲烷菌属的产甲烷菌。一个有趣的发现是Caproiciproducens属中稀有细菌的出现，这是导致己酸产量增加的原因。