In Situ Reduction of Fe-Doped Calcium Carbonate to Perform Low-Carbon Cement Clinker Coupling with Generation of Syngas

作者：Shaokang Yu, Jingyi Guo, Ming Xu, Weitao Zhang, Dabing Guo, Y.H. Wang, Zhen Xue, Hong Yan, Yusen Yang, Jingrui Fang, Mingfei Shao, Xue Duan · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.5c03469 · 被引用次数：8 · 研究领域：Chemical Looping and Thermochemical Processes、Catalytic Processes in Materials Science、Catalysis and Oxidation Reactions

In situ reduction of carbonates is an efficient strategy to prepare cement with lower CO 2 emission and energy consumption. However, the important role of Fe species in CaCO 3 still lacks comprehensive and in-depth research. Herein, we report on the preparation of a low-carbon cement clinker coupling high-value syngas via the in situ reduction process of Fe-doped CaCO 3 . The optimal 3 wt % Fe–CaCO 3 exhibits an ultrahigh CO selectivity (99.2%) at 600 °C with a CO formation rate of 0.67 mmol min –1, which significantly reduces the decarboxylation temperature and inhibits CO 2 emissions. A combination of advanced in situ characterization and density functional theory calculations has demonstrated that Fe species facilitate the hydrogen dissociation, and the process undergoes a temperature-dependent reduction mechanism. At relatively low temperatures, CO is produced via the direct hydrogenation mechanism; i.e., the active H species initially binds to O in C–2O on the carbonate, selectively cleaving Ca–O and C–O bonds to generate CO*. At elevated temperatures, the reverse water gas shift pathway with HCOO* species as intermediates is executed. This study elucidates the mechanism of Fe-doped CaCO 3 hydrogenation as raw materials for cement, thereby providing a novel avenue for the practical large-scale application of low-carbon cement coupled with syngas.