Propane Steam Reforming over Catalysts Derived from Noble Metal (Ru, Rh)-Substituted LaNiO(3) and La(0.8)Sr(0.2)NiO(3) Perovskite Precursors

The propane steam reforming (PSR) reaction was investigated over catalysts derived from LaNiO(3) (LN), La(0.8)Sr(0.2)NiO(3) (LSN), and noble metal-substituted LNM(x) and LSNM(x) (M = Ru, Rh; x = 0.01, 0.1) perovskites. The incorporation of foreign cations in the A and/or B sites of the perovskite structure resulted in an increase in the specific surface area, a shift of XRD lines toward lower diffraction angles, and a decrease of the mean primary crystallite size of the parent material. Exposure of the as-prepared samples to reaction conditions resulted in the in situ development of new phases including metallic Ni and La(2)O(2)CO(3), which participate actively in the PSR reaction. The LN-derived catalyst exhibited higher activity compared to LSN, and its performance for the title reaction did not change appreciably following partial substitution of Ru for Ni. In contrast, incorporation of Ru and, especially, Rh in the LSN perovskite matrix resulted in the development of catalysts with significantly enhanced catalytic performance, which improved by increasing the noble metal content. The best results were obtained for the LSNRh(0.1)-derived sample, which exhibited excellent long-term stability for 40 hours on stream as well as high propane conversion (X(C3H8) = 92%) and H(2) selectivity (S(H2) = 97%) at 600 °C.