Biomass-to-sustainable Biohydrogen: Insights into the Production Routes, and Technical Challenges

Hydrogen is regarded as one of the utmost competent alternative fuels in the transition to net-zero emissions for the future. Nowadays, it is still majorly derived from non-renewable energy resources (i.e., fossil fuels). Regrettably, a key issue for the reliance on these depleted resources is the extremely negative impacts on our milieu. The emergence of envisioned biomass-to-sustainable H2 strategy is viewed as an appealing opportunity to generate a sustainable strategic H2. This review article summarizes the patented approaches (thermochemical, biological, and electrochemical) for H2 production from an enticing raw material of biomass. The optimization of different prominent parameters to achieve the eventual easiest way for H2 production was additionally discussed. The advancement in different operational parameters, technical challenges, and scalable improvement of each pathway was briefly addressed. Moreover, the contemporary economic viewpoints on the bankable biomass-to-H2 processes flow diagrams in terms of the circular economy were additionally highlighted in order to effectively value the biomass supply chains to produce H2. Hopefully, this work presents a more favorable theoretical in-depth mechanistic understanding of the bio-sourced hydrogen's different production pathways.