Investigation of transition metal-modified biochar as catalysts in the co-pyrolysis of corn cob and polyethylene for enhanced hydrogen production

Hydrogen is an important clean energy source for the future and an essential building block for achieving sustainable development plans and net-zero emissions. This study investigates transition metal-modified biochar catalysts and the effect of temperature on the co-pyrolysis of biomass and plastics for hydrogen-rich gas production. Biochar was modified with Ni and Co, and characterized using XRD, SEM, BET, and FT-IR. The catalysts' performance was assessed by analyzing the distribution of solid, liquid, and gaseous products, along with bio-oil and syngas composition. The 10Ni5Co catalyst showed the highest hydrogen production efficiency at 600 degrees C pyrolysis and 800 degrees C reforming, with a H2 selectivity of 37.66 % and H2 yield of 15.05 mmol/g. The optimal pyrolysis temperature ensures proper feedstock decomposition, while the reforming temperature enhances catalyst activity. The 10Ni5Co catalyst exhibited excellent stability, with H2 selectivity only decreasing from 37.66 % to 32.01 % after three cycles. Despite structural degradation at 850 degrees C, biochar modification increased surface area, allowing for higher transition metal loading. These findings are of great practical significance for promoting the application of biochar-based catalysts in the field of hydrogen production from biomass.