Abstract
Iron manganese oxides are prepared using a coprecipitation procedure and studied for the conversion of synthesis gas to light olefins and hydrocarbons. In particular, the effect of a range of preparation variables such as [Fe]/[Mn] molar ratios of the precipitation solution, pH of precipitation, temperature of precipitation, and precipitate aging times was investigated in detail. The results are interpreted in terms of the structure of the active catalyst and it has been generally concluded that the calcined catalyst (at 650 ∘C for 6 hours) containing 50%Fe/50%Mn‐on molar basis which is the most active catalyst for the conversion of synthesis gas to light olefins. The effects of different promoters and supports with loading of optimum support on the catalytic performance of catalysts are also studied. It was found that the catalyst containing 50%Fe/50%Mn/5 wt.%Al2O3 is an optimum‐modified catalyst. The catalytic performance of optimal catalyst has been studied in operation conditions such as a range of reaction temperatures, H2/CO molar feed ratios and a range of total pressures. Characterization of both precursors and calcined catalysts is carried out by powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), BET specific surface area and thermal analysis methods such as TGA and DSC.
Highlights
Fischer-Tropsch (FT) synthesis is of great industrial importance due to the great variety of products obtained such as paraffins, olefins and alcohols
In this part of study, we have investigated the effect of a range of iron manganese oxide catalysts preparation variables at the precursor stage upon the structure of these materials, and the subsequent influence these structural effects have on the activity of the final calcined catalysts
We demonstrated the importance of aging time with respect to catalyst activity for oxidation of CO by mixed copper manganese oxide and mixed copper zinc oxide catalysts [27,28,29,30,31,32,33,34,35] and for hydrogenation of CO by mixed of cobalt-iron oxide, cobalt-manganese oxide, and cobaltcerium oxide catalysts for Fischer-Tropsch synthesis [36,37,38,39,40]
Summary
Fischer-Tropsch (FT) synthesis is of great industrial importance due to the great variety of products obtained such as paraffins, olefins and alcohols. An approach to improve the selectivity of the classical Fischer-Tropsch (FT) process for conversion of synthesis gas to hydrocarbons involves the use of a bifunctional catalyst system containing a metal catalyst (FT catalyst) combined with a support. Compared to other metal catalysts for Fischer-Tropsch (FT) synthesis, an iron-based catalyst is distinguished by higher conversion, selectivity to the lower olefins, and flexibility to the process parameters [8, 9]. The Fe–Mn catalyst, as one of the most important catalyst systems, has received extensive attention in recent years because of the higher olefin and middle distillation cut selectivities which allow their products to be used as a feedstock for the chemical industry. The effects of operation conditions such as H2/CO molar feed ratios, a range of reaction temperatures and total pressures for conversion of synthesis gas to light olefins have been studied
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
