Zhou, Xuan; Wang, Xinxing; Li, Jiaqi; Zhang, Ranqing; Lin, Tiejun; An, Yunlei; Zhong, Liangshu

INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

2024, 64, 1520-5045

Zhou, Xuan; Wang, Xinxing; Li, Jiaqi; Zhang, Ranqing; Lin, Tiejun; An, Yunlei; Zhong, Liangshu

Fischer-Tropsch synthesis to olefins (FTO) from syngas with low CO2 selectivity achieves great attention but still remains challenging. Herein, Pr-promoted metallic Co catalysts were applied to the FTO reaction, and the promotional effect was investigated in detail. All Pr-promoted catalysts displayed higher olefin selectivity and lower methane selectivity compared with the unpromoted Co-based catalysts. Moreover, the CO2 selectivity was significantly suppressed, owing to the low intrinsic activity of metallic Co sites for the water-gas shift reaction (WGSR). The optimal Pr loading was found to be 10 wt %, which resulted in a high olefin selectivity of 44.1% and a low CO2 selectivity of 1.1%. The structural characterization revealed that the addition of Pr altered the electronic state of Co species, leading to enhanced CO adsorption and a low H/C ratio on the catalyst surface. Furthermore, secondary hydrogenation activity was also inhibited by adding the Pr promoter, which is favorable for olefin production.