Effect of Support Pretreatment Temperature on the Performance of an Iron Fischer–Tropsch Catalyst Supported on Silica-Stabilized Alumina

Catalysts

William C. Hecker¹  Kamyar Keyvanloo¹  Trent Okeson¹  Baiyu Huang²  Hussein H. Hamdeh³ 

[1] Department of Chemical Engineering, Brigham Young University, Provo, UT 84602, USA;Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA;Department of Physics, Wichita State University, Wichita, KS 67260, USA;

关键词: Fischer–Tropsch synthesis;    supported iron catalyst;    silica-stabilized alumina;    support pretreatment temperature;    iron carbide;   

DOI  :  10.3390/catal8020077

来源: DOAJ

【 摘 要 】

The effect of support material pretreatment temperature, prior to adding the active phase and promoters, on Fischer–Tropsch activity and selectivity was explored. Four iron catalysts were prepared on silica-stabilized alumina (AlSi) supports pretreated at 700 °C, 900 °C, 1100 °C or 1200 °C. Addition of 5% silica to alumina made the AlSi material hydrothermally stable, which enabled the unusually high support pretreatment temperatures (>900 °C) to be studied. High-temperature dehydroxylation of the AlSi before impregnation greatly reduces FeO·Al2O3 surface spinel formation by removing most of the support-surface hydroxyl groups leading to more effectively carbided catalyst. The activity increases more than four-fold for the support calcined at elevated temperatures (1100–1200 °C) compared with traditional support calcination temperatures of <900 °C. This unique pretreatment also facilitates the formation of ε′-Fe2.2C rather than χ-Fe2.5C on the AlSi support, which shows an excellent correlation with catalyst productivity.

【 授权许可】

Unknown