The transition to a carbon-free society is a global goal, and hydrogen is emerging as a hopeful avenue in achieving this goal. The International Energy Agency forecasts that 115 million tons of hydrogen will be needed in 2030 to achieve net-zero carbon dioxide emissions by 2050.
Green hydrogen, produced from renewable sources such as biomass, is becoming an attractive option due to its potential to decrease carbon emissions caused by fossil fuels.
One of the latest advances in hydrogen production technology is the alkaline thermal treatment (ATT) of biomass. This process involves pyrolysis at atmospheric pressure and low temperature, which has the potential to reduce carbon emissions significantly and replace some fossil fuels. The process’s considerable ability for “negative carbon emissions” makes it a promising candidate for green hydrogen production.
In a recent review published in the KeAi journal Carbon Resources Conversion, a research group analyzed the latest developments in ATT technology for hydrogen production. The team aimed to understand the fundamental role and synergy of alkali and catalysts in the ATT reaction and the conversion mechanism of biomass.
The review revealed four significant conclusions. First, further study is required to comprehend the transformation of model substances via different alkalis and determine the most suitable biomass. Second, an analysis should be performed to fix an ideal catalyst system based on the intermediate products of the ATT reaction. This analysis should consider the deactivation mechanism of the catalyst, the interaction between the active site and carrier, and the catalytic structure-activity relationship.
Third, designing rational reactors and developing effective inlet or outlet methods are essential in overcoming issues like coking, limited mass transfer, and catalyst regeneration caused by solid-solid reactions when weighing the benefits and drawbacks of in-situ and ex-situ reactions. Finally, economic assessment and energy consumption analysis must be performed to assess the technology’s viability.
Houfang Lu, a professor at the School of Chemical Engineering at Sichuan University, emphasized the need to optimize hydrogen production efficiency from the ATT reaction. To achieve this, the alkali used must promote biomass conversion into small gas intermediates and in-situ carbon storage. Moreover, by overcoming the kinetic limitation of the reformation reaction under low pressure and temperature in the ATT process, hydrogen production efficiency can be enhanced, and the synergy between alkali and metal catalysts can be fully demonstrated.
Lu hopes that the review’s conclusions will guide future experiments on hydrogen production via biomass ATT processes to realize the technology’s industrialization.
The potential impact of green hydrogen production using ATT technology is significant, as it can help reduce carbon emissions and aid in achieving a carbon-free society. However, challenges surrounding this technology include the need for further research and development, as well as economic and energy consumption analysis.
In conclusion, ATT technology for biomass hydrogen production is a promising avenue for achieving a carbon-free society. However, it requires significant research and development to optimize its efficiency and overcome challenges. If successful, green hydrogen production using biomass could play a vital role in reducing carbon emissions and creating a sustainable future.