Synergistic Effect of Alkali Na and K Promoter on Fe-Co-Cu-Al Catalysts for CO2 Hydrogenation to Light Hydrocarbons

Catalysts

Xia Zhang¹  Jie Liu¹  Chenghua Xu¹  Qiong Wu¹  Yuhao Zheng¹ 

[1] College of Resources and Environment, Chengdu University of Information Technology, Chengdu 610225, China;

关键词: Fe-Co@Cu alloy;    CO₂ hydrogenation;    dissociative adsorption;    light hydrocarbons;   

DOI  :  10.3390/catal11060735

来源: DOAJ

【 摘 要 】

Alkali metal K- and/or Na-promoted FeCoCuAl catalysts were synthesized by precipitation and impregnation, and their physicochemical and catalytic performance for CO₂ hydrogenation to light hydrocarbons was also investigated in the present work. The results indicate that Na and/or K introduction leads to the formation of active phase metallic Fe and Fe-Co crystals in the order Na < K < K-Na. The simultaneous introduction of Na and K causes a synergistic effect on increasing the basicity and electron-rich property, promoting the formation of active sites Fe@Cu and Fe-Co@Cu with Cu⁰ as a crystal core. These effects are advantageous to H₂ dissociative adsorption and CO₂ activation, giving a high CO₂ conversion with hydrogenation. Moreover, electron-rich Fe@Cu (110) and Fe-Co@Cu (200) provide active centers for further H₂ dissociative adsorption and O-C-Fe intermediate formation after adsorption of CO produced by RWGS. It is beneficial for carbon chain growth in C₂⁺ hydrocarbons, including olefins and alkanes. FeCoCuAl simultaneously modified by K-Na exhibits the highest CO₂ conversion and C₂⁺ selectivity of 52.87 mol% and 89.70 mol%, respectively.

【 授权许可】

Unknown