Dry Reforming of Methane on Ni-Containing La2O3 and La2O3–Mn2O3 Catalysts: Effect of the Preparation Method

Abstract

Nickel-containing supported catalysts based on oxides La₂O₃ and La₂O₃–Mn₂O₃ (n_La/n_Mn = 1/1) synthesized by various methods have been studied in dry reforming of methane (DRM). The effect of the synthesis method on the phase composition and structure of the supports and the catalysts has been studied by low-temperature nitrogen adsorption, X-ray powder diffraction, transmission electron microscopy, and Raman spectroscopy. Deficient lanthanum manganite synthesized by the citrate method interacts with nickel ions to form LaNi_xMn_1–xO₃ in the surface layer. In the course of reduction of the oxidized precursor with hydrogen, particles of the active component are formed from NiO and LaNi_xMn_1 – xO₃, and the proportion between them depends on the ordering of the LaMnO_3 + δ support. The H₂ : CO ratio changes from 0.7 to 0.8 for the Ni/LaMnO₃ and Ni/La₂O₃ catalysts, respectively; however, for the perovskite sample, no carbon deposition is observed for 8.5 h.