Carbon-negative hydrogen production technology

Hydrogen is considered the “ultimate power” of the 21st century, offering benefits such as cleanliness, renewable ability, shelf life, and versatility. The International Energy Agency estimates that 115 million tons of hydrogen is needed in 2030 to reduce global carbon dioxide emissions to zero by 2050. This makes green hydrogen a promising path to a carbon-neutral society.

By using biomass to produce hydrogen, we can reduce carbon emissions from fossil fuels, helping to address a worsening energy crisis. A new alkaline pyrolysis (ATT) technology for hydrogen generation incorporates atmospheric pressure and low-temperature pyrolysis. From the perspective of the entire life cycle of biomass, ATT has a significant potential for “negative carbon emissions” and could replace some fossil fuels.

In one KeAi magazine Transfer of carbon resources In a published review, a team of researchers comprehensively examined recent advances in ATT for hydrogen production biomass. “There are many factors that affect the efficiency of hydrogen production from ATT biomass,” explains first author of the study Guojie Liu, a doctoral student in the School of Chemical Engineering at Sichuan University. “This includes, but is not limited to, alkalis, feedstocks, catalysts, process standards, and reactors.”

However, we must first elucidate the essential and synergistic role of alkali and catalysts in the ATT reaction and biomass conversion mechanism, and then use this knowledge to guide the development of more effective and even breakthrough upgrading strategies in large-scale applications, he said further.

To maximize the efficiency of hydrogen production from the ATT reaction, the alkali used should enhance the conversion of biomass into a small gasifiable intermediate and in situ carbon storage.

“Furthermore, by overcoming the kinetic limit of the low-pressure and low-temperature reforming reaction in the ATT process, the hydrogen production efficiency can be increased and the synergy between alkaline and metallic catalysts can be fully demonstrated,” said Huafang Lu, a professor at the same school.

After the research, four important conclusions were drawn. More studies are needed to better understand the transformation of model materials by different alkalis and to find more suitable biomass. In order to establish a suitable catalyst system based on intermediates for the ATT reaction, the mechanism of catalyst deactivation, the interaction between the active site and the support, and the relationship between structure and catalytic activity must be analyzed. Furthermore, when evaluating the advantages and disadvantages of in situ and ex situ reactions, designing suitable reactors and developing efficient inlet/outlet methods are key to overcoming problems such as coking, limited mass transfer and catalyst regeneration caused by solid solids. Feedback occurs. Finally, an economic evaluation and analysis of energy consumption must also be performed.

“We hope these points will play a role in future experiments on hydrogen generation using biomass ATT processes to manufacture this technology,” Lu said.