Enhancement of Light Olefins Selectivity Over N-Doped Fischer-Tropsch Synthesis Catalyst Supported on Activated Carbon Pretreated with KMnO₄

• Main Authors: Zhipeng Tian, Chenguang Wang, Zhan Si, Chengyan Wen, Ying Xu, Wei Lv, Lungang Chen, Xinghua Zhang, Longlong Ma
• Format: Article
• Language: English
• Published: MDPI AG 2019-05-01
• Series: Catalysts
• Subjects: nitrogen-doping; iron nitrides; light olefins; CO hydrogenation; KMnO₄ pretreatment
• Online Access: https://www.mdpi.com/2073-4344/9/6/505

Ammonium iron citrate was used as an iron precursor in order to prepare N-doped catalysts supported on KMnO₄ pretreated activated carbon (10MnK-AC). Iron nitride was synthesized in company with the formation of α-Fe₂O₃ on 10MnK-AC. The characterizations of the catalysts show that nitrogen atoms were doped into iron lattice rather than the networks of the carbon support. The performance of Fischer-Tropsch synthesis to light olefins (FTO) suggest an improvement in O/P ratio (olefins to paraffins molar ratio of C₂−C₄) over the iron catalysts supported on 10MnK-AC. The further promotion of light olefins selectivity (up to 44.7%) was obtained over FeN-10MnK-AC catalyst owing to the collaborative contribution of the electron donor effect of nitrogen and the suppression effect on the second hydrogenation over 10MnK-AC support.