Existing CO₂-mediated oxidative dehydrogenation (CO₂-ODH) of ethane has yet to demonstrate >60% single-pass CO yield due to the intrinsic equilibrium limitations. We report a unique approach with mixed molten carbonates as a reaction medium for CO₂-ODH, which strategically partitions the CO₂-ODH reactions into gas and molten-salt phases and facilitates integrated CO₂ capture from power plant flue gases. An 89% CO yield was achieved at 770°C, doubling the equilibrium limitation of conventional CO₂-ODH. The high CO yield in turn enhances ethylene formation. Further characterizations confirmed that molten-salt mediated ODH (MM-ODH) proceeds through a gas-phase cracking and molten-salt mediated reverse water-gas-shift reaction pathway. Based on this understanding, thermodynamic analysis and ab initio molecular dynamics simulations were conducted to develop general principles to optimize the molten-salt reaction medium. Process analyses confirm that MM-ODH has the potential to be significantly more efficient for CO₂ capture and utilization than conventional CO₂-ODH.

由于固有的平衡限制，现有的 CO ₂介导的乙烷氧化脱氢 (CO ₂ -ODH) 尚未证明 >60% 的单程 CO 产率。我们报告了一种使用混合熔融碳酸盐作为 CO ₂ -ODH反应介质的独特方法，该方法将 CO ₂ -ODH 反应战略性地划分为气相和熔盐相，并有助于从电厂烟道气中集成 CO ₂捕获。在 770°C 下实现了 89% 的 CO 产率，是传统 CO ₂的平衡限制的两倍-ODH。高 CO 产率反过来又促进了乙烯的形成。进一步的表征证实，熔盐介导的 ODH (MM-ODH) 通过气相裂解和熔盐介导的反向水煤气变换反应途径进行。基于这种理解，进行了热力学分析和从头分子动力学模拟，以制定优化熔盐反应介质的一般原则。过程的分析证实，MM-ODH必须是对CO显著更高效的潜力₂捕获和利用比常规CO ₂ -ODH。