Industrial & Engineering Chemistry Research, Vol.58, No.42, 19386-19396, 2019
110th Anniversary: Dry Reforming of Methane over Ni- and Sr-Substituted Lanthanum Zirconate Pyrochlore Catalysts: Effect of Ni Loading
Pyrochlores are thermally stable materials that can be doped with a metal to produce active catalyst for dry reforming of methane (DRM). La1.95Sr0.05Zr1.904Ni0.096O7-d (LSNZ1) and La1.95Sr0.05Zr1.44Ni0.56O7-d (LSNZ6), with 1 and 6 wt % Ni loading at Zr site, respectively, were investigated for DRM. XRD of fresh catalysts confirmed the formation of pyrochlore structure. Also, the presence of the La2NiZrO6 perovskite phase and NiO phase indicated low substitution of Ni in the pyrochlore structure. TPSR and DRM long runs carried out at 900 degrees C and 45 h time on stream confirmed that LSNZ6 was more active than LSNZ1, which is attributed to higher Ni content and dispersion of Ni in LSNZ6. In both the catalysts, the pyrochlore structure was stable during the reaction, but the perovskite phase was reduced to respective metal oxides. No carbon deposition was observed on both the catalysts during 900 degrees C DRM runs for 45 h. Also, no sintering of catalyst was observed from XRD and TPR.