Fischer–Tropsch Synthesis: Effects of Aging Time and Operating Temperatures on Solvothermally Prepared Nanocatalyst for Light Olefin Selectivity

2017 ◽  
Vol 147 (5) ◽  
pp. 1221-1234 ◽  
Author(s):  
Tahereh Taherzadeh Lari ◽  
Ali Akbar Mirzaei ◽  
Hossein Atashi
Reactions ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 227-257
Author(s):  
Arash Yahyazadeh ◽  
Ajay K. Dalai ◽  
Wenping Ma ◽  
Lifeng Zhang

Light olefins as one the most important building blocks in chemical industry can be produced via Fischer–Tropsch synthesis (FTS) from syngas. FT synthesis conducted at high temperature would lead to light paraffins, carbon dioxide, methane, and C5+ longer chain hydrocarbons. The present work focuses on providing a critical review on the light olefin production using Fischer–Tropsch synthesis. The effects of metals, promoters and supports as the most influential parameters on the catalytic performance of catalysts are discussed meticulously. Fe and Co as the main active metals in FT catalysts are investigated in terms of pore size, crystal size, and crystal phase for obtaining desirable light olefin selectivity. Larger pore size of Fe-based catalysts is suggested to increase olefin selectivity via suppressing 1-olefin readsorption and secondary reactions. Iron carbide as the most probable phase of Fe-based catalysts is proposed for light olefin generation via FTS. Smaller crystal size of Co active metal leads to higher olefin selectivity. Hexagonal close-packed (HCP) structure of Co has higher FTS activity than face-centered cubic (FCC) structure. Transition from Co to Co3C is mainly proposed for formation of light olefins over Co-based catalysts. Moreover, various catalysts’ deactivation routes are reviewed. Additionally, techno-economic assessment of FTS plants in terms of different costs including capital expenditure and minimum fuel selling price are presented based on the most recent literature. Finally, the potential for global environmental impacts associated with FTS plants including atmospheric and toxicological impacts is considered via lifecycle assessment (LCA).


RSC Advances ◽  
2018 ◽  
Vol 8 (56) ◽  
pp. 32073-32083 ◽  
Author(s):  
Chuanxue Zhu ◽  
Yingxin Liu ◽  
Chao Huo ◽  
Huazhang Liu

The effects of the surfactant hexadecyltrimethylammonium bromide (CTAB) on the catalytic performance of a manganese-promoted iron (FeMn) catalyst for the Fischer–Tropsch to olefin (FTO) reaction were investigated.


RSC Advances ◽  
2019 ◽  
Vol 9 (25) ◽  
pp. 14176-14187 ◽  
Author(s):  
Sunkyu Yang ◽  
Sungwoo Lee ◽  
Seok Chang Kang ◽  
Seung Ju Han ◽  
Ki-Won Jun ◽  
...  

Intimate contact between Fe5C2 and Na2O leads to high linear olefin selectivity with minimizing branched paraffin formation.


Author(s):  
Majid Sarkari ◽  
Farhad Fazlollahi ◽  
Hossein Atashi

The effects of K, Ce, Zn, Cs, and Rb promoters on the structure and catalytic behavior of precipitated 50%Fe/50%Mn catalyst in Fischer–Tropsch synthesis (FTS) were investigated in a fixed-bed reactor. The effects of promoter on Fischer-Tropsch iron catalysts caused an increased growth probability of hydrocarbon chains from 0.67 to 0.75 for K to Rb promoter, and the olefin/paraffin ratios increased from 0.99 to 1.36 for Rb to K-promoted catalyst. The effect on the olefin selectivity was certainly due to increased adsorption strength of CO causing an enhanced displacement of olefin. The catalysts were assessed in terms of their FTS activity and product selectivity using Anderson–Schulz–Flory (ASF) models. The effects of various reaction conditions such as flow rates, temperatures, and H2/CO feed ratios were studied and process synthesis concepts were used to investigate interactions between the optimum regions for reactor operation and the experimental results.


Author(s):  
Ed Durham ◽  
Christopher B. Roberts

Previous research has demonstrated that supercritical phase Fischer Tropsch Synthesis (SC-FTS) using hexanes as the solvent medium offers superior activity maintenance to traditional fixed-bed (gas phase) Fischer Tropsch Synthesis (GP-FTS) (Elbashir et al., 2005). This has prompted an investigation into whether supercritical media can reactivate a catalyst used in GP-FTS. To that end, a study was conducted in which a series of GP-FTS experiments of approximately 2 days each were performed, separated by in situ periods of catalyst reactivation using supercritical hexanes as well as SC-FTS.It was found that the supercritical hexanes media and SC-FTS reactivation periods were effective in partially restoring lost catalyst activity and selectivity. GP-FTS was demonstrated to have detrimental effects on subsequent SC-FTS operation while SC-FTS operation showed beneficial effects on subsequent GP-FTS operation. Specifically, SC-FTS reactivations reduced the methane selectivity in subsequent GP-FTS periods. The CO2 selectivity in SC-FTS is consistently lower than that in GP-FTS, while the olefin selectivity into the diesel range is higher in SC-FTS. While the propagation probability was initially higher in SC-FTS than GP-FTS, the propagation probability values converged as the experiment progressed.


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