Combustion synthesis of NiO-CaO-Al2O3 catalysts for biomass gasification of eucalyptus wood for sustainable H2 production

Resumo

Hydrogen energy is the cleanest among alternative sources, producing only water during combustion and achieving true "zero emissions." Biomass gasification involves partial oxidation at high temperatures (700–1200°C), generating gases such as H₂, CO, CH₄, and CO₂. Nickel is widely used as the active phase in catalysts due to its low cost and high selectivity for H₂, while calcium acts as a CO₂ adsorbent, indirectly increasing H₂ production. NiO-CaO-Al₂O₃ catalysts were synthesized via combustion using urea and metal nitrates. The materials were characterized by TG and XRD. Thermogravimetric analysis indicated carbonaceous residues in samples containing calcium. These materials were calcined at 600–800°C to remove residues and obtain the desired phases. After calcination, mixtures of spinel phases (MAl₂O₄) and segregated oxides were formed. These catalysts were tested in biomass gasification at high temperatures, showing promising results in H₂ production.