Three-Dimensionally Ordered Macroporous La2O3-Supported Ni Catalyst for Methane Dry Reforming

Three-dimensionally ordered macroporous (3DOM) La2O3-supported Ni catalysts exhibit outstanding performance for methane dry reforming (DRM). The 5Ni/La2O3-3DOM catalyst achieves 79% CH4 and 84% CO2 conversions at 800 °C under the reaction conditions of atmospheric pressure, CH4:CO2 molar ratio of 1:1, and gas hourly space velocity (GHSV) = 36,000 mL·gcat−1·h−1, outperforming its counterparts (5Ni/La2O3-PP prepared by means of co-precipitation and 5Ni/La2O3-GNC prepared by means of glycine–nitrate combustion) by 15–20%. Long-term stability tests at 700 °C (same CH4:CO2 ratio and GHSV as above) show that the 5Ni/La2O3-3DOM catalyst maintains CH4 and CO2 conversions at approximately 80% and 85%, respectively, with zero deactivation over 50 h. Meanwhile, its carbon deposition rate plummets to 1.1 mg·g−1·h−1, which is 75% lower than that of the precipitation-derived 5Ni/La2O3-PP catalyst. This excellent performance stems from the synergy of nano-confined Ni particles (11.2 nm in crystallite size after reduction) and abundant surface oxygen species (38 μmol·g−1), establishing 3DOM La2O3 as a superior anti-coking support platform for scalable H2 production via DRM.