A novel integrated CO₂ capture and utilization (CCU) process for direct methanation was proposed to reduce the total required thermal energy by effectively combining CO₂ capture and conversion using a Ni/CaO catal-sorbent. Compared to the conventional carbonation/decarbonation process, carbonated Ni/CaO catal-sorbents were regenerated by converting captured CO₂ to CH₄ under a H₂ atmosphere at temperatures lower than those required for CO₂ desorption. According to the theoretical and experimental results, the optimum reaction temperature for the novel CCU process was determined at 500 °C; while the Ni/CaO catal-sorbent exhibited high CO₂ capture and direct methanation capacity without sintering during consecutive cycle tests at 500 °C. Therefore, this new integrated CCU process for direct methanation could be a cost- and energy-effective approach to CH₄ production and climate emergency mitigation.

中文翻译：

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使用Ni / CaO催化吸附剂的新型集成式CO2捕获和直接甲烷化工艺

提出了一种新型的直接甲烷化的集成CO ₂捕集和利用（CCU）工艺，以通过使用Ni / CaO阳离子吸附剂有效结合CO ₂捕集和转化来减少总所需的热能。与常规的碳化/脱碳方法相比，通过在低于CO ₂解吸所需温度的H ₂气氛下，通过将捕获的CO ₂转化为CH ₄来再生碳酸盐化的Ni / CaO阳离子吸附剂。根据理论和实验结果，确定了新型CCU工艺的最佳反应温度为500°C。Ni / CaO阳离子吸附剂的CO ₂含量较高在500°C的连续循环测试中无需烧结即可捕获和直接甲烷化能力。因此，这种新的直接甲烷化的综合CCU工艺可能是CH ₄生产和缓解气候紧急情况的一种经济高效的方法。