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

Abstract

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.