Effects of different Al₂O₃ support on HDPE gasification for enhanced hydrogen generation using Ni-based catalysts

This study examined the effects of Ni loading on different types of alumina (γ-Al₂O₃, mesoporous Al₂O₃, 13 nm-sized Al₂O₃, and <50 nm-sized Al₂O₃) for high-density polyethylene gasification for enhanced hydrogen generation. The catalytic activity of Ni loaded alumina was observed in the order of 13 nm-sized Al₂O₃> mesoporous Al₂O₃> (<50 nm-sized Al₂O₃) > γ-Al₂O₃ for the gas yield and γ-Al₂O₃> (<50 nm Al₂O₃) > mesoporous Al₂O₃ > 13 nm Al₂O₃ for the oil yield, respectively. In addition, the production of hydrogen from Ni loaded alumina showed an increasing trend in the order of (<50 nm-sized Al₂O₃) > γ-Al₂O₃> 13 nm-sized Al₂O₃.> mesoporous Al₂O₃. In contrast, CO showed the trend as Ni/mesoporous Al₂O₃> Ni/13 nm-sized Al₂O₃> Ni/γ-Al₂O₃> (Ni/<50 nm Al₂O₃). The highest level of hydrogen production from the Ni/<50 nm-sized Al₂O₃ catalyst might be because of its highest Ni dispersion and surface area. The use of Ni-loaded nm-sized alumina could be an excellent method for increased hydrogen production compared to other types of alumina available.