Selectivity For Lower Olefins Research Articles

CO2 hydrogenation to synthetic natural gas with light hydrocarbons on Mn-promoted mesoporous Co3O4-Al2O3 metal oxides

Direct CO2 conversion into synthetic natural gas (SNG, CH4) with simultaneous small production of light paraffinic C2-C4 hydrocarbons to enhance a heating value of SNG was investigated with ordered mesoporous CoMnAl mixed metal oxides (denoted as m-CoMnAl). CO2 hydrogenation activity to form hydrocarbons with small CO byproduct formed by a reverse water gas shift reaction (RWGS) was strongly affected by the MnO2 promoter content in the ordered Co3O4-Al2O3 mesoporous structures. The m-CoMnAl structures with proper amount of Mn promoter were found to be effective to enhance CO2 conversion to methane with small amount of light hydrocarbons formation, which were mainly attributed to the presence of abundant oxygen vacant sites with a stable preservation of the partially oxidized cobalt nanoparticles in the ordered mesoporous Co3O4-Al2O3 structures even under a reductive hydrogenation condition. Selective methanation of CO2 was found to be more favorable on the highly reduced metallic cobalt nanoparticles formed with smaller amount of Mn promoter (m-CoMnAl(0.05)), however, excessive Mn content such as Mn/Co ratio > 1 (m-CoMnAl(1.0)) revealed less structural stability of ordered mesoporous structures with lower CO2 conversion with relatively higher CO selectivity of 1.4 % with lower olefin selectivity through severe phase segregations of the Co-Mn-Al mixed metal oxides with selective formations of MnCO3 phases.

Investigation of AFeO3 (A=Ba, Sr) Perovskites for the Oxidative Dehydrogenation of Light Alkanes under Chemical Looping Conditions.

Oxidative dehydrogenation (ODH) of light alkanes to produce C2-C3 olefins is a promising alternative to conventional steam cracking. Perovskite oxides are emerging as efficient catalysts for this process due to their unique properties such as high oxygen storage capacity (OSC), reversible redox behavior, and tunability. Here, we explore AFeO3 (A=Ba, Sr) bulk perovskites for the ODH of ethane and propane under chemical looping conditions (CL-ODH). The higher OSC and oxygen mobility of SrFeO3 perovskite contributed to its higher activity but lower olefin selectivity than its Ba counterpart. However, SrFeO3 perovskite is superior in terms of cyclic stability over multiple redox cycles. Transformations of the perovskite to reduced phases including brownmillerite A2Fe2O5 were identified by X-ray diffraction (XRD) as a cause of performance degradation, which was fully reversible upon air regeneration. A pre-desorption step was utilized to selectively tune the amount of lattice oxygen as a function of temperature and dwell time to enhance olefin selectivity while suppressing CO2 formation from the deep oxidation of propane. Overall, SrFeO3 exhibits promising potential for the CL-ODH of light alkanes, and optimization through surface and structural modifications may further engineer well-regulated lattice oxygen for maximizing olefin yield.

Machine learning aided catalyst activity modelling and design for direct conversion of CO2 to lower olefins

In the recent years, the demand for utilisation of CO2 into different chemicals has gathered interest due to increased concerns for global warming. The current work focuses on development of machine learning (ML) framework for catalyst modelling and design for direct conversion of CO2 to lower olefins (LO) based on the structural-composition-operating parameters. Comprehensive review, and data mining exercise was carried out and data base was formed from -55 relevant reports, including 18 input parameters and catalyst activity (i.e., CO2 conversion (%) & LO selectivity (%)) as output parameter. Artificial neural network (ANN) models were developed using Bayesian-Regularisation (BR) and Levenberg-Marquardt (LM) backpropagation learning algorithms for prediction of catalyst activity. Performance of the developed ANN models are compared with linear, tree-based, and kernel-based ML models and has been evaluated based on statistical measures. Out of these ML models, ANN-BR is able to predict CO2 conversion & LO selectivity with less deviation from experimental data (R = 0.90 & 0.8, RMSE = 8.43 & 16.73, AAD = 5.8 & 9.5 for test data respectively), compared to other ML models. Input contribution on post analysis of modelling is considered to understand the significance of predominate feature affecting the target variables. Further, integrated catalyst and process design carried out using inverse design based on multi-objective optimization (NSGA-II) with ANN-BR as objective function. Results indicate two-to-three-folds increase in yields with optimal catalyst composition, operating conditions, and novel combination of catalysts for efficient conversion of CO2 to lower olefins compared to reported experimental results.

Recent advances in oxidative dehydrogenation of propane to propylene on boron-based catalysts

ABSTRACT Oxygen-assisted oxidative dehydrogenation of propane (O2-ODHP) to propylene is a promising route that complements the existing oil-based processes to bridge the gap between continuously increasing market demand and productivity of propylene. This reaction i) is free from thermodynamic constraint and ii) features minimized coke deposition of the catalyst. A major challenge of ODHP lies in the over-oxidation to undesired carbon oxides (COx). Transition metal oxides have been extensively explored in the past decades; however, they suffer from a low olefin selectivity. Most recently, hexagonal boron nitride (h-BN) emergesas a promising candidate for ODHP, which shows a unique high selectivity toward light olefins (C2-C3) and negligible COx formation. To interpret the origin of such unique catalytic performance, significant efforts have been put forth in identifying active sites and developing an in-depth understanding of reaction mechanisms through combined experimental and computational approaches. In general, boron-oxide species are identified as the active sites, and a surface-induced gas-phase reaction mechanism has been proposed, though detailed scenarios vary. These findings explain the Eley-Rideal kinetic behavior and unique high olefin selectivity of h-BN. The breakthrough in h-BN catalysts revitalizes the exploration of boron-oxide catalysts because of their identical kinetic behavior and similar active sites to h-BN catalysts. With the accumulated knowledge, continuous endeavor is devoted to developing advanced boron-containing materials for enhanced activity and durability. This review aims to summarize the recent advances in ODHP on boron-based catalysts, with particular emphases on catalytic performance, kinetic behavior, stability and leaching issues, identification of active sites, and site-dependent reaction mechanisms, as well as the development of advanced boron-based materials. With this review, we expect to not only provide an overview to keep abreast of the state-of-the-art boron-containing catalytic materials for ODHP, but also to identify key descriptors for designing efficient boron-based catalysts with low-temperature activity.

Bifunctional catalysts composed of low silicon‐content SAPO‐34 nanosheets and In2O3/ZrO2 with improved performance for CO2 hydrogenation

AbstractThe conversion of CO2 into high‐value chemicals has drawn a great deal of consideration, of which the most ideal product is lower olefins. However, the modified Fischer–Tropsch (F‐T) synthesis with CO as an intermediate shows poor selectivity for lower olefins. Here, a list of bifunctional catalysts consisting of SAPO‐34 zeolites with adjustable silicon contents and In2O3/ZrO2 were synthesized. In the reaction process, CO2 is first hydrogenated to methanol over an In2O3/ZrO2 catalyst, and then the generated methanol rapidly diffuses to the adjacent zeolite catalyst to react to lower olefins. The selectivity of lower olefins (88.3%) and conversion rate of CO2 (23.3%) was achieved over In2O3/ZrO2 and SAPO‐34‐0.05 at 633 K, a gas hourly space velocity (GHSV) of 4500 ml·gcat–1·h–1, and H2/CO2/Ar = 3:1:1. The catalytic performance remained stable after 50 h of reaction. Characterization analysis showed that Si content affected the content of Brønsted acid sites (BAS) and morphology of SAPO‐34, resulting in different distribution of reaction intermediates. Tetramethyl‐benzenes, as important intermediate species, had a slower conversion rate on the SAPO‐34 with low Si content and nanosheet morphology, which led to high lower olefins selectivity. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.

Tuning the electronic property of Pd nanoparticles by encapsulation within ZIF-67 shells towards enhanced performance in 1,3-butadiene hydrogenation

The low olefin selectivity of Pd-based catalysts is a long-term challenge for the selective hydrogenation of 1,3-butadiene.

Facile and Rapid Synthesis of Durable SSZ-13 Catalyst Using Choline Chloride Template for Methanol-to-Olefins Reaction

In the current study, a facile and rapid synthesis approach for a SSZ-13 catalyst using choline chloride (CC) as a template was proposed, and the catalytic performance for the methanol-to-olefins (MTO) reaction was examined. With a proper amount of CC addition (i.e., m(CC)/m(SiO2) = 0.14), uniform and homogeneously distributed cubic SSZ-13 crystals were obtained within 4 h with lower aggregation. The synthesized catalyst demonstrated excellent porous features with a total specific surface area and mesopore volume of 641.71 m2·g−1 and 0.04 cm3·g−1, respectively. The optimized strong and weak acid sites on SSZ-13 were obtained by regulating the m(CC)/m(SiO2) ratio. The less strong acid sites and a larger amount of weak acid sites in the synthesized catalyst were conducive to the catalytic performance of the MTO reaction under a lower reaction temperature (450 °C). The appropriate acidity and well-developed pore structure of synthesized SSZ-13 could also slow down the carbon deposition rate and, thus, significantly improve the catalytic lifetime of the catalyst. The methanol conversion rate and initial selectivity of light olefin using the synthesized catalyst could maintain over 95% and 50%, respectively, and a lifetime of 172 min was achieved. Although the low olefin selectivity of the synthesized SSZ-13 catalyst was slightly lower than that of the purchased one, its desirable features were thought to have good potential for industrial application.

Relay catalysis in the conversion of syngas

China’s energy resource structure is rich in coal but poor in crude oil. For a long time, China has to rely on importing crude oil to meet the domestic demand for liquid fuels (including gasoline, aviation fuel and diesel fuel) and basic chemicals (such as C2–C4 lower olefins, aromatics, and C2+ oxygenates). In 2019, China’s dependence on oil imports has exceeded 70%, which has a negative impact on the social-economic development and national security. Thus, it is very urgent and important to produce liquid fuels and bulk chemicals based on coal resource. Syngas (a mixture of CO and H2) can be largely produced from the non-oil resources, such as coal, gas (natural gas, shale gas, and coal-bed methane), and biomass. From syngas, various hydrocarbon products can be produced as supplement of oil-derived products. The conversion of syngas to target products with high selectivity is the core of C1 chemistry. However, by the classical Fischer-Tropsch synthesis (FTS) route, the product selectivity is limited by the Anderson-Schulz-Flory (ASF) distribution, which results in the low selectivity of target products. In practice, the yields of liquid fuels and bulk chemicals are increased by a secondary process such as (hydro)cracking, isomerization and aromatization. The direct conversion of syngas to target products with high selectivity is attractive but challenging. Recently, the concept of relay catalysis has been successfully applied to the one-step transformation of syngas to liquid fuels and bulk chemicals with ultrahigh selectivity over bifunctional or multifunctional catalysts. The selectivity of target hydrocarbon products can break the limitation of the ASF distribution. In the conversion of syngas to liquid fuels, the used bifunctional catalysts are composed of FT catalysts and zeolites. FT catalysts, such as Fe (Fe x C y ), Co and Ru, are responsible for the activation of CO and the growth of carbon chain. Zeolites are in charge of the hydrocracking and isomerization. High selectivity of middle-distillates, such as gasoline (C5–C11 hydrocarbons), jet fuel (C8–C16 hydrocarbons) and diesel fuel (C10–C20 hydrocarbons), have been obtained via relay catalysis. It was found that the catalytic performances were strongly influenced by the topology, acidity and mesoporosity of zeolites as well as the metal sizes and promoters. The importance of hydrocracking on acid sites and hydrogenolysis on the metal nanoparticles for the selective C–C cleavage has also been analyzed. The selective synthesis of basic chemicals can also be achieved by relay catalysis, where the bifunctional catalysts consist of metal oxides (such as the solution solid ZnO-ZrO2, and the spinel structure of ZnCr2O4, ZnAl2O4) and zeolites (such as SAPO-34, ZSM-5, MOR). The activation of CO to intermediates (CH3OH/DME or ketene) proceeds on the metal oxides and the selective C–C bond formation proceeds on the zeolites. The reaction mechanism of such kind of bifunctional catalysts differs from that of the conventional FT catalysts, where the CO activation and C–C coupling are conducted over different sites. The selectivity of lower olefins and aromatics could reach up to 85% without the formation of undesired methane. Besides, multifunctional catalysts can offer an 80% selectivity towards C2+ oxygenates such as methyl acetate, acetic acid, and ethanol by coupling CO activation and carbonylation. The product selectivity of oxygenates was significantly impacted by the zeolite acidity and the proximity between the two functional components. The present review not only summarizes the major advantages and disadvantages of the relay catalysis in syngas conversion but also offers prospects for future development of relay catalysis in syngas conversion.

Lignin-Derived Graphene-Like Carbon Nanosheets as an Efficient Catalyst Support for Fischer-Tropsch Synthesis

Bio-renewable lignin has been used as a precursor for the preparation of various carbon materials, such as carbon fibers, ordered mesoporous carbon and graphite carbon cages. Nevertheless, up to now, there are few studies about prepare graphene-like carbon nanosheets derived from lignin. In this study, we synthesized graphene-like carbon nanosheets, using lignin as the precursor, via one-step pyrolysis route. Fortunately, physical and chemical characterization results indicate that it has high pore volume and hierarchical pore with wrinkled sheet graphene structure. Furthermore, the capability of graphene-like carbon nanosheets was investigated as a catalyst support in Fischer-Tropsch synthesis. The results of catalytic evaluation show that Fe₂O₃/GCNs has excellent catalytic activity and the selectivity of lower olefins, compared with Fe₂O₃/AC.

NiO-based ceramic structured catalysts for ethylene production: Substrates and active sites

Structured catalysts have important advantages compared to powder formulations and they are required for processes intensification. In this work, three different ceramic structures: a cordierite monolith, an alumina foam and an alumina-silica paper were used as substrates for the deposition of a NiO-Al2O3 coating and tested in the oxidative dehydrogenation of ethane to produce ethylene. For comparison, a NiO-Al2O3 powder catalyst was also prepared. Nickel oxide species with different physicochemical features were obtained over each structure, evidenced by morphological (SEM-EDX) and physicochemical characterization (XRD, LRS and XPS). The best distributions of the catalytic coatings and NiO physicochemical properties were obtained when the monolith and the foam were used as substrates. These led to higher NiO-Al2O3 interactions and consequently to high ethylene selectivity values, 70–90 %, corresponding to the former an ethane conversion of 22 % and to the latter a 5 %. The distribution of the active phase on the ceramic paper was heterogeneous, with NiO agglomerations and poor NiO-support interaction thus achieving low olefin selectivity (∼ 30 %). The addition of a second element such as cerium was also studied in those structured catalysts with high selectivity, resulting in both cases in an increment of ethane conversion but a decrease in ethylene selectivity. This behavior was attributed to the generation of electrophilic oxygen species.

Strong metal-support interaction (SMSI) of Pt/CeO2 and its effect on propane dehydrogenation

Upon reduction at 975 °C, a strong metal-support interaction (SMSI) of CeO2 on Pt NPs leads to low rates for ethylene hydrogenation and propane dehydrogenation, but high olefin selectivity for the latter reaction. By contrast, reduction at 550 °C of Pt/CeO2, leads to 5 nm Pt NP’s with ethylene hydrogenation and propane dehydrogenation TORs and low olefin selectivity similar to Pt/SiO2. X-ray absorption fine structure (EXAFS) and scanning transmission electron microscopy (STEM) shows formation of ∼15 nm monometallic Pt nanoparticles partially covered by SMSI CeO2. The propylene selectivity of Pt NP’s covered by SMSI CeO2 was ∼95 % suggesting there were few Pt ensembles capable of catalysing propane hydrogenolysis; while the remaining exposed Pt remain active for dehydrogenation reactions.

Enhanced catalytic behavior for methanol to lower olefins over SAPO-34 composited with ZrO2

A microporous SAPO-34 molecular sieve was tailored via a surface compositing strategy of a mesoporous t-ZrO2 with both L acid and base characteristics. A hydrothermal coating method was employed to successfully fabricate the SAPO-34/t-ZrO2 catalyst with a distinct chemical interphase, which showed excellent catalytic activity and lifetime during the conversion of methanol to lower olefins. At ambient pressure and a reaction temperature of 380 °C, the methanol conversion reached 100% and the selectivity for lower olefins was over 90%. The catalyst lifetime reached 1130 min, which was an increase of 770 min compared to using unmodified SAPO-34. By using the physically-blend catalyst t-ZrO2/SAPO-34 and the unmodified SAPO-34 as references, the MTO reaction and carbon deposit behaviors of the surface composited catalyst were determined. Via a hydrothermal coating method to modify the molecular sieve, the fabricated complex solid solution interphase effectively regulated the Si distribution on surface of SAPO-34. The SAPO-34/t-ZrO2 mainly contained synergic active centers of B acid and lesser amounts of L acid-base, as well as a micro-mesoporous system, which were crucial to decrease the carbon deposition formation rate. By studying the in situ IR and carbon deposition, it was revealed that abundant various kinds of active centers and the micro-mesoporous system in the SAPO-34/t-ZrO2 modified catalyst allowed large long-chain alkyl benzenes to form. This novel catalytic behavior effectively inhibited the cyclization and polycondensation of the carbon deposit precursors, leading to an excellent resistance to deactivation induced by carbon deposition.

Unraveling the Twin and Tunability of the Crystal Domain Sizes in the Medium-Pore Zeolite ZSM-57 by Electron Crystallography.

Tailoring the morphology of a specific crystalline material through distinct crystal growth mechanisms (classical and nonclassical) is challenging. Herein, we report the two unique morphologies of a medium-pore (10×8-ring) zeolite, ZSM-57, prepared by employing an identical organic structure-directing agent (OSDA) and different inorganic cations, namely Na+ and K+ , denoted as ZSM-57-Na (pentagonal nanoplates) and ZSM-57-K (pentagonal nanoprisms), respectively. The tunable twin domain size and twin boundaries in both samples have been unraveled at the atomic level by electron crystallography. It is of significance to note that the 10-ring pore openings run perpendicular to the pentagonal nanoplates and nanoprisms. Moreover, the distinct crystal growth mechanisms, which result in the different unique morphologies and tunable twin domains, were further determined by electron crystallography combined with other techniques. Nonclassical growth involving the aggregation of amorphous aluminosilicate nanoparticles to the smooth ZSM-57-Na crystal surface dominates the ZSM-57-Na crystallization process. For the ZSM-57-K sample, the classical layer-by-layer growth through the addition of silica molecules to advancing steps on the crystal surface dominates the ZSM-57-K crystallization process. The different morphologies of both samples result in the distinct catalytic lifespan of the methanol conversion and selectivity of lower olefins.

Conversion of jatropha oil into lower olefins over zeolite catalysts in the presence of water

ABSTRACTA simple method, supplying water with Jatropha oil, was proposed to enhance the conversion of selectivity of lower olefins over zeolite catalysts, H-ZSM-5 and SAPO-11. The yield of lower olefins was as high as 54 C mol%, and the selectivity for lower olefins reached 58 C mol%. The optimum condition on catalytic conversion of jatropha oil was 600 °C of reaction temperature, 3.0 s of contact time and 0.7 of water fraction with SAPO-11. The presence of water effectively suppressed the progress of Diels-Alder and hydrogen transfer reaction probably due to the reduced number of acid sites.

Comparison of preparation methods of iron-based catalysts for enhancing Fischer-Tropsch synthesis performance

Carbon supported iron catalysts for Fischer-Tropsch synthesis, with the same iron loading of ca. 35 wt.%, were prepared by pyrolysis process and incipient wetness impregnation methods. The effect of the preparation methods on the catalyst structure, catalytic properties, and the direct conversion of syngas via Fischer-Tropsch synthesis was investigated. The iron species, iron particle size and iron reducibility depended on the preparation method. The pyrolysis of homogeneous fusion yielded a unique core-shell structure with dispersed iron species embedded in a matrix of porous carbon. The FeOx/AC catalyst obtained by incipient wetness impregnation contained Fe2O3 species after calcination, while the core-shell structured catalyst obtained by pyrolysis process contained Fe3C species after calcination. The results show that the core-shell structure iron-based catalyst had higher extent of carburization and dispersion, which led to higher activity for Fischer-Tropsch reaction than that of other two catalysts obtained by different synthesis methods. Furthermore, the Fe3C@C catalyst promoted by alkali metals (Na, Mg, K, Ca) resulted in the increase of O/P ratio and low carbon olefin selectivity, and the decrease of methane selectivity.

Direct and Highly Selective Conversion of Synthesis Gas into Lower Olefins: Design of a Bifunctional Catalyst Combining Methanol Synthesis and Carbon–Carbon Coupling

AbstractThe direct synthesis of lower (C2 to C4) olefins, key building‐block chemicals, from syngas (H2 /CO), which can be derived from various nonpetroleum carbon resources, is highly attractive, but the selectivity for lower olefins is low because of the limitation of the Anderson–Schulz–Flory distribution. We report that the coupling of methanol‐synthesis and methanol‐to‐olefins reactions with a bifunctional catalyst can realize the direct conversion of syngas to lower olefins with exceptionally high selectivity. We demonstrate that the choice of two active components and the integration manner of the components are crucial to lower olefin selectivity. The combination of a Zr–Zn binary oxide, which alone shows higher selectivity for methanol and dimethyl ether even at 673 K, and SAPO‐34 with decreased acidity offers around 70 % selectivity for C2–C4 olefins at about 10 % CO conversion. The micro‐ to nanoscale proximity of the components favors the lower olefin selectivity.

Direct and Highly Selective Conversion of Synthesis Gas into Lower Olefins: Design of a Bifunctional Catalyst Combining Methanol Synthesis and Carbon-Carbon Coupling.

The direct synthesis of lower (C2 to C4) olefins, key building-block chemicals, from syngas (H2/CO), which can be derived from various nonpetroleum carbon resources, is highly attractive, but the selectivity for lower olefins is low because of the limitation of the Anderson-Schulz-Flory distribution. We report that the coupling of methanol-synthesis and methanol-to-olefins reactions with a bifunctional catalyst can realize the direct conversion of syngas to lower olefins with exceptionally high selectivity. We demonstrate that the choice of two active components and the integration manner of the components are crucial to lower olefin selectivity. The combination of a Zr-Zn binary oxide, which alone shows higher selectivity for methanol and dimethyl ether even at 673 K, and SAPO-34 with decreased acidity offers around 70% selectivity for C2-C4 olefins at about 10% CO conversion. The micro- to nanoscale proximity of the components favors the lower olefin selectivity.

Fabrication of K-promoted iron/carbon nanotubes composite catalysts for the Fischer–Tropsch synthesis of lower olefins

K-promoted iron/carbon nanotubes composite (i.e., FeK-OX) was prepared by a redox reaction between carbon nanotubes and K2FeO4 followed by thermal treatments on a purpose as the Fischer–Tropsch catalyst for the direct conversion of syngas to lower olefins. Its catalytic behaviors were compared with those of the other two Fe-IM and FeK-IM catalysts prepared by impregnation method followed by thermal treatments. The novel FeK-OX composite catalyst is found to exhibit higher hydrocarbon selectivity, lower olefins selectivity and chain growth probability as well as better stability. The catalyst structure-performance relationship has been established using multiple techniques including XRD, Raman, TEM and EDS elemental mapping. In addition, effects of additional potassium into the FeK-OX composite catalyst on the FTO performance were also investigated and discussed. Additional potassium promoters further endow the catalysts with higher yield of lower olefins. These results demonstrated that the introduction method of promoters and iron species plays a crucial role in the design and fabrication of highly active, selective and stable iron-based composite catalysts for the FTO reaction.

Fischer-Tropsch synthesis on Co-Al2O3-(promoter)/ZSM5 hybrid catalysts for the production of gasoline range hydrocarbons

The Fischer-Tropsch synthesis (FTS) reaction was investigated for the direct production of gasoline range hydrocarbons (C5-C9) from syngas on Ru-, Pt- and La-promoted Co-Al2O3/ZSM-5 (Si/Al=25) hybrid catalysts prepared by co-precipitation method in a slurry. The hybrid catalysts were characterized by BET surface area, XRD, H2-TPR and NH3-TPD analyses. Their physicochemical properties were correlated with the activity and selectivity of the catalysts. The promoted Co-Al2O3-(promoter)/ZSM-5 hybrid catalysts were superior to the unpromoted Co-Al2O3/ ZSM-5 catalyst in terms of better C5-C9 yield. In particular, the Co-Al2O3-Pt/ ZSM-5 hybrid catalyst exhibited the highest catalytic activity with a low C1 and olefin selectivity and a high C5-C9 selectivity. It could be due to not only a higher value for the reduction degree by H2-TPR, but also assigned to weak acidic sites of a low temperature desorption peak by NH3-TPD.

One-pot synthesis of promoted porous iron-based microspheres and its Fischer–Tropsch performance

Promoter modified porous iron-based microspheres were prepared through one pot solvothermal method, and employed as catalysts during Fischer–Tropsch (FT) synthesis. Specially, a microsphere was consist of nanoparticles and pores. The effect of promoter and pore on CO conversion and on lower olefins selectivity was investigated. Fe/K and Fe/Zn displayed a high selectivity to CH4 (>0wt%), which was not desirable for their application in the FT process. Na doped Fe/Na catalyst displayed optimum catalytic performance. In particular, it showed an excellent selectivity toward C5+ (59.0wt%) while yielding a CH4 product fraction lower than 11.3wt%. Fe/Mn catalyst showed a C2-4 olefins selectivity approximately 34.1wt%, but only achieved a CO conversion of 37.4%. Furthermore, the results showed that pore size of catalysts played a key role on morphology of catalysts and on catalytic performance with time on stream.