Low-Temperature Methane to Ethylene Catalyst: High-Entropy Lanthanoid Oxide Shows Stable 240-Hour OCM Performance

Researchers at Institute of Science Tokyo and University of Tokyo have developed a high-entropy lanthanoid oxide catalyst that converts methane into ethane and ethylene at record-low temperatures. The catalyst, made from lanthanum, samarium, europium, gadolinium, and dysprosium, starts producing C2 hydrocarbons at 525 degrees Celsius and reaches a 12.3 percent C2 yield at 600 degrees Celsius, far below the roughly 800 degrees Celsius needed by conventional oxidative coupling of methane (OCM) catalysts. Unlike earlier OCM catalysts that lose activity quickly, the material held its performance for 240 hours of continuous operation, with a deactivation rate more than 25 times lower than the single-oxide equivalents. The team linked the low-temperature activity to moderately basic surface sites and showed that average ionic radius can be used to tune those sites, giving chemists a design parameter instead of trial-and-error screening. If the approach scales beyond lab nanoparticles, it could lower the energy and carbon footprint of making ethylene and ethane from natural gas. That matters for industrial decarbonization because the chemical sector currently relies on energy-intensive syngas routes. A demonstration unit and life-cycle analysis would be the next steps to test whether the lab results survive real-world feed conditions.