Explorando aditivos para mejorar la producción fermentativa de biohidrógeno

Abstract

Dark fermentation appears as a promising strategy in the

new energy landscape, as it enables the production of

biohydrogen using a wide range of biomass substrates, thus

also contributing to waste management. However, this process

exhibits lower yields compared to conventional thermochemical

processes for H2 production, such as reforming. To overcome

this limitation, the use of additives has been explored to

enhance microbial activity and increase dark fermentation

yields. However, the application of additives remains limited in

practice. This study aims to address this gap by examining the

effects of three types of additives (zero-valent iron, activated

carbon, and hydrochar) on dark fermentation and hydrogen

generation. The results reveal that hydrochar shows the most

promising outcomes, increasing H2 production by 20.3%, with

the highest biohydrogen yield at 92 mLH2/g-glucose. Volatile

fatty acid analysis reveals that butyric and acetic pathways

are utilized for H2 production in this case. It is also important

to consider the alkalinity of the feedstock, as high levels can

increase the pH in the medium and promote methane (CH4)

production as the main fermentation product instead of H2.

When this occurs, Fe(0) NPs appear to be the additive that

most favors methane generation, resulting in a 6.1% higher

production compared to the control experiment. This confirms

the interest in the use of certain additives in fermentative

processes.