The air-steam catalytic gasification of rice husk for hydrogen-rich gas production was experimentally investigated in a combined fixed bed reactor with the newly developed nano-NiO/γ-Al2O3 catalyst. A series of experiments have been performed to explore the effects of catalyst presence, catalytic reactor temperature, the equivalence ratio (ER), and steam to biomass ratio (S/B) on the composition and yield of gasification gases. The experiments demonstrated that the developed nano-NiO/γ-Al2O3 catalyst had a high activity of cracking tar and hy...