Achieving nearly 100 % CO2 conversion via CaCO3‑carbon reverse Boudouard reaction in an integrated CO2 capture and utilization process using carbon as the reducing agent (C-ICCU)

作者：Xiaotong Zhao, Jia Hu, Bo Zong, Yuanyuan Wang, Jye‐Chyi Lu, Chunfei Wu · 发表于：Chemical Engineering Journal · 年份：2025 · DOI：10.1016/j.cej.2025.168153 · 被引用次数：15 · 研究领域：Carbon Dioxide Capture Technologies、Catalysts for Methane Reforming、Membrane Separation and Gas Transport

Hydrogen-driven CO 2 utilization technologies have attracted significant attention in recent years. However, large-scale implementation is constrained by the high energy demands and limited availability of sustainable H 2 sources, which are often derived from fossil fuels or rely on energy-intensive water electrolysis. To address this challenge, we propose an alternative approach by introducing solid carbon as a reductant in the integrated CO 2 capture and utilization (ICCU) process via the reverse Boudouard reaction. In this study, we investigate the feasibility and mechanism of this carbon-mediated ICCU (C-ICCU) pathway by examining the reaction between CaCO 3 and nickel-supported carbon materials (Ni/activated charcoal and Ni/graphite). Our experimental results reveal that the CaCO 3 &Ni/carbon system achieves nearly 100 % CO 2 conversion at 600 °C, with sustained high performance at elevated temperatures (90 % at 650 °C and 88 % at 800 °C for Ni/graphite). Notably, the presence of nickel significantly enhances the direct reactions between CaCO 3 and carbon, circumventing the need for thermal decomposition of CaCO 3 , which otherwise introduces unconverted CO 2 . In contrast, non-catalytic systems exhibit minimal CO 2 conversion, underscoring the critical role of metal catalysts in this process. In-situ DRIFTS, Raman, and XPS analyses demonstrate that Ni facilitates a direct interfacial reaction between CaCO 3 and carbon, circumventing the need for CaCO 3 to thermally deco...