Catalytic steam reforming of rice straw biomass to hydrogen-rich syngas over Ni-based catalysts

Abstract

Ni-based catalysts with SiO2, γ-Al2O3, CaO, and TiO2 as supports and MgO-7.5% Ni/γ-Al2O3 catalysts with different contents of MgO were prepared. The structure of the catalysts was characterized by powder X-ray diffraction and N2 adsorption-desorption measurements. The performance of the catalysts in the steam reforming of rice straw biomass to syngas was evaluated. The effects of reaction conditions on the activity of the catalysts were also investigated. Ni-based catalysts supported on γ-Al2O3 had higher catalytic activity than the catalysts supported on TiO2, CaO, and SiO2. The yield of H2 reached 1071.3 ml H2/g biomass and the ratio of H2 to CO was 1.4:1 over a 7.5% Ni/γ-Al2O3 catalyst. Addition of MgO to the 7.5% Ni/γ-Al2O3 catalyst improved its catalytic activity. The yield of H2 reached 1194.6 ml H2/g biomass and the ratio of H2 to CO was 3.9:1 over the 1.0% MgO-7.5% Ni/γ-Al2O3 catalyst. MgO not only improves the steam reforming reaction of Ni-based catalysts, but can also promote the water-gas shift reaction. This method shows promise for production of H2-rich syngas from biomass.