Stabilized ε-Fe2C catalyst with Mn tuning to suppress C1 byproduct selectivity for high-temperature olefin synthesis
Fei Qian, Jiawei Bai, Yi Cai, Hui Yang, Xuemin Cao, Xingchen Liu, Xingwu Liu, Yong Yang, Yongwang Li, Ding Ma, Xiaodong Wen
Abstract
Abstract Accurately controlling the product selectivity in syngas conversion, especially increasing the olefin selectivity while minimizing C1 byproducts, remains a significant challenge. Epsilon Fe 2 C is deemed a promising candidate catalyst due to its inherently low CO 2 selectivity, but its use is hindered by its poor high-temperature stability. Herein, we report the successful synthesis of highly stable ε-Fe 2 C through a N-induced strategy utilizing pyrolysis of Prussian blue analogs (PBAs). This catalyst, with precisely controlled Mn promoter, not only achieved an olefin selectivity of up to 70.2% but also minimized the selectivity of C1 byproducts to 19.0%, including 11.9% CO 2 and 7.1% CH 4 . The superior performance of our ε-Fe 2 C-xMn catalysts, particularly in minimizing CO 2 formation, is largely attributed to the interface of dispersed MnO cluster and ε-Fe 2 C, which crucially limits CO to CO 2 conversion. Here, we enhance the carbon efficiency and economic viability of the olefin production process while maintaining high catalytic activity.