Establishment of the upstream processing for renewable production of hydrogen using vermicomposting-tea and molasses as substrate

This study aimed to establish the optimal operational conditions for hydrogen production using vermicomposting-tea and sugarcane molasses as substrate. The experiments were carried out by triplicate in 110 ml serological bottles, a Box-Behnken design of experiments was performed in anaerobic dark conditions. The maximal hydrogen production (HP), hydrogen production rate (HPR), and hydrogen yield (HY) attained were 1021.0 mlL(-1), 5.32 mlL(-1)h(-1), and 60.3 mlL(H2)(-1) /g(TCC), respectively. The statistical model showed that the optimal operational conditions for pH, molasses concentration, and temperature were 6.5; 30 % (v/v) and 25 ?. The bioreactor run showed 17.202 L of hydrogen, 0.58 Lh(-1), and 77.2 ml(H2)g(TCC)(-1) For HP, HPR, and HY. Chemometric analysis for the volatile fatty acids obtained at the fermentation showed that only two principal components are required to explain 90 % of the variance. The representative pathways for hydrogen production were acetic and butyric acids. This study established the operational conditions for the upstream processing amenable to pilot and industrial-scale operations. Our results add value to molasses within the circular economy for hydrogen production using a novel consortium from vermicompost.

Automated summary

This study established the optimal operational conditions for hydrogen production using vermicomposting-tea and sugarcane molasses as substrate, providing guidance for pilot and industrial-scale operations.