Opening Direct Electrochemical Fischer-Tropsch Synthesis Path by Interfacial Engineering of Cu Electrode with P-Block Elements

The electrochemical synthesis of syngas (CO and H2) has garnered considerable attention in the context of Fischer-Tropsch (FT) synthesis employing thermal catalysts. Nonetheless, the need for a novel, cost-effective technique persists. In this investigation, we introduce a direct electrochemical (dEC) approach for FT synthesis that functions under ambient conditions by utilizing a p-block element (Sn and In) overlaid Cu electrode. Surface *CO and H* species were obtained in an electrolytic medium through the CO2 + H+ + e- → HOOCad → *CO (or direct CO adsorption) and H+ + e- → H* reactions, respectively. We have observed C2-7 long-chain hydrocarbons with a CnH2n+2/CnH2n ratio of 1-3, and this observation can be explained through the process of C-C coupling chain growth of the conventional FT synthesis, based on the linearity of the Anderson-Schulz-Flory equation plots. Thick Sn and In overlayers resulted in the dominant production of formate, while CO and C2H4 production were found to be proportional and inversely correlated to H2, C2H6, and C3-7 hydrocarbon production. The EC CO2/CO reduction used in dEC FT synthesis offers valuable insights into the mechanism of C2+ production and holds promise as an eco-friendly approach to producing long-chain hydrocarbons for energy and environmental purposes.

New reaction path for long-chain hydrocarbons by electrochemical CO2 and CO reduction over Au/stainless steel

The Fischer-Tropsch (F-T) synthesis is recognized for its ability to produce long-chain hydrocarbons. In this study, we aimed to replicate F-T synthesis using electrochemical CO2 reduction and CO reduction reactions on a stainless steel (SS) support with a gold (Au) overlayer. Under CO2-saturated conditions, the presence of Au on the SS surface led to the formation of CH4 and a range of hydrocarbons (CnH2n and CnH2n+2, n = 2-7), while bare SS primarily produced hydrogen. The Au(10 nm)/SS exhibited the highest hydrocarbon production in CO2-saturated phosphate, indicating a synergistic effect at the Au-SS interface. In CO-saturated conditions, bare SS also produced long-chain hydrocarbons, but increasing Au thickness resulted in decreased production due to poor CO adsorption. Hydrocarbons were formed through both direct and indirect CO adsorption pathways. Anderson-Schulz-Flory analysis confirmed surface CO hydrogenation and C-C coupling polymerization following conventional F-T synthesis. The C2 hydrocarbons exhibited distinct behavior compared to C3-5 hydrocarbons, suggesting different reaction pathways. Despite low reduction product levels, our EC method successfully replicated F-T synthesis using the Au/SS electrode, providing valuable insights into C-C coupling mechanisms and electrochemical production of long-chain hydrocarbons. Depth-profiling X-ray photoelectron spectroscopy revealed significant changes in surface elemental compositions before and after EC reduction.

Catalytic Technologies for CO Hydrogenation for the Production of Light Hydrocarbons and Middle Distillates

In South Korea, where there are no resources such as natural gas or crude oil, research on alternative fuels has been actively conducted since the 1990s. The research on synthetic oil is subdivided into Coal to Liquid (CTL), Gas to Liquid (GTL), Biomass to Liquid (BTL), etc., and was developed with the focus on catalysts, their preparation, reactor types, and operation technologies according to the product to be obtained. In Fischer–Tropsch synthesis for synthetic oil from syngas, stability, CO conversion rate, and product selectivity of catalysts depends on the design of their components, such as their active material, promoter, and support. Most of the developed catalysts were Fe- and Co-based catalysts and were developed in spherical and cylindrical shapes according to the reactor type. Recently, hybrid catalysts in combination with cracking catalysts were developed to control the distribution of the product. In this review, we survey recent studies related to the design of catalysts for production of light hydrocarbons and middle distillates, including hybrid catalysts, encapsulated core–shell catalysts, catalysts with active materials with well-organized sizes and shapes, and catalysts with shape- and size-controlled supports. Finally, we introduce recent research and development (R&D) trends in the production of light hydrocarbons and middle distillates and in the catalytic processes being applied to the development of catalysts in Korea.

Opportunities for less-explored zeolitic materials in the syngas-to-olefins pathway over nanoarchitectured catalysts: a mini review

The continuous demand for olefins has stimulated recent research to develop appropriate technology to produce olefins from alternative resources.

Direct oxide transfer from an η2-keto ligand to generate a cobalt PCcarbeneP(O) pincer complex

We report the direct carbonyl cleavage in a κ³-P′,(η²-C,O),P′′ ligand by a monomeric cobalt centre through metal–ligand cooperativity.

Effects of Co/Ce molar ratio and operating temperature on nanocatalyst performance in the Fischer–Tropsch synthesis

The effect of Co/Ce molar ratios on the catalytic performance in FTS.

The origin of Mo promotion during H2 pretreatment on an Fe catalyst for Fischer–Tropsch synthesis

The Mo promotion on Fischer–Tropsch Fe catalysts is related to Mo dispersion on Fe surface during H₂ pretreatment. The resulting strong Fe–Mo interaction disfavors the activation of CO molecules on active Fe sites and consequently reduced the intrinsic activity.

Large-scale synthesis of uniformly loaded cobalt nanoparticles on alumina for efficient clean fuel production

The Co/Al₂O₃ nanocatalyst prepared with tens of gram scale in a batch, showed good CO conversion (∼76%), very high CTY value (∼1.4 × 10⁻⁴ mol_CO g_Co⁻¹ s⁻¹) and remarkable hydrocarbon productivity (∼1.0 g_HC g_cat⁻¹ h⁻¹) under controlled FTS conditions.

Robust iron-carbide nanoparticles supported on alumina for sustainable production of gasoline-range hydrocarbons

A robust iron-carbide/alumina catalyst shows excellent catalytic performance for selective production of liquid fuels.

Combined Operando X-ray Diffraction/Raman Spectroscopy of Catalytic Solids in the Laboratory: The Co/TiO2 Fischer-Tropsch Synthesis Catalyst Showcase

A novel laboratory setup for combined operando X-ray diffraction and Raman spectroscopy of catalytic solids with online product analysis by gas chromatography is presented. The setup can be used with a laboratory-based X-ray source, which results in important advantages in terms of time-on-stream that can be measured, compared to synchrotron-based experiments. The data quality was much improved by the use of a relatively high-energy MoKα radiation instead of the more conventional CuKα radiation. We have applied the instrument to study the long-term deactivation of Co/TiO2 Fischer-Tropsch synthesis (FTS) catalysts. No sign of Co sintering or bulk oxidation was found during the experiments. However, part of the metallic Co was converted into cobalt carbide (Co2C), at elevated pressure (10 bar). Furthermore, graphitic-like coke species are clearly formed during FTS at atmospheric pressure, whereas at elevated pressure fluorescence hampered the interpretation of the measured Raman spectra.

Solar photothermochemical alkane reverse combustion

A one-step, gas-phase photothermocatalytic process for the synthesis of hydrocarbons, including liquid alkanes, aromatics, and oxygenates, with carbon numbers (Cn) up to C13, from CO2 and water is demonstrated in a flow photoreactor operating at elevated temperatures (180-200 °C) and pressures (1-6 bar) using a 5% cobalt on TiO2 catalyst and under UV irradiation. A parametric study of temperature, pressure, and partial pressure ratio revealed that temperatures in excess of 160 °C are needed to obtain the higher Cn products in quantity and that the product distribution shifts toward higher Cn products with increasing pressure. In the best run so far, over 13% by mass of the products were C5+ hydrocarbons and some of these, i.e., octane, are drop-in replacements for existing liquid hydrocarbons fuels. Dioxygen was detected in yields ranging between 64% and 150%. In principle, this tandem photochemical-thermochemical process, fitted with a photocatalyst better matched to the solar spectrum, could provide a cheap and direct method to produce liquid hydrocarbons from CO2 and water via a solar process which uses concentrated sunlight for both photochemical excitation to generate high-energy intermediates and heat to drive important thermochemical carbon-chain-forming reactions.

Ultrathin N-rich boron nitride nanosheets supported iron catalyst for Fischer–Tropsch synthesis

The Fe/BNNSs catalysts were firstly fabricated for the Fischer–Tropsch synthesis, which exhibited appreciable FTS activity, selectivity and good stability over 270 h.

The effect of the unpaired d-orbital electron number in Fe and Co catalysts on Fischer–Tropsch synthesis

The unpaired d-orbital electron number was calculated, and the results showed that it can be used as an indicator in Fischer–Tropsch synthesis.

Highly productive cobalt nanoparticles supported on mesocellular silica foam for the Fischer–Tropsch reaction

The Co/MCF nanocatalyst containing well-dispersed and highly loaded Co nanoparticles exhibits very high hydrocarbon productivity in Fischer–Tropsch synthesis.

Active phase distribution changes within a catalyst particle during Fischer–Tropsch synthesis as revealed by multi-scale microscopy

A new combination of three chemical imaging methods has been developed and applied to fresh and spent co-based Fischer–Tropsch catalysts.

Study on Fe–Co alloy role over RANEY® Fe–Co bimetallic catalysts in Fischer–Tropsch synthesis

Supersaturated R-Fe_0.2Co_0.8 and R-Fe_0.1Co_0.9 catalysts exhibited the best CO conversion and higher C₅₊ selectivity.

Fischer–Tropsch synthesis: effect of Cu, Mn and Zn addition on activity and product selectivity of cobalt ferrite

The effect of Cu, Mn and Zn addition on cobalt ferrite was investigated for FT synthesis. The FT activity remains more or less the same for all four catalysts at higher temperatures. Zn and Mn were found to promote alcohol formation.

Hydrothermal preparation of Fe–Zr catalysts for the direct conversion of syngas to light olefins

Two-step hydrothermal preparation of Fe/Zr–K catalysts could improve the olefin selectivity and product distribution by reducing the secondary hydrogenation ability and suppressing the formation of heavy hydrocarbons during CO hydrogenation.

Influence of gas-to-liquid (GTL) fuel in the combined blend of Jatropha biodiesel and diesel: an analysis of engine combustion–performance–emission parameters

This study presents a comparative analysis of the blends of JBD (J20) and GTL fuel (G20) with diesel, including a ternary blend of JBD-GTL-diesel (DJG20), in the context of fuel properties, engine performance and emission characteristics.

Cs promoted Fe5C2/charcoal nanocatalysts for sustainable liquid fuel production

Cs promoted Fe₅C₂/charcoal nanocatalysts especially at Cs/Fe = 0.025, prepared by a melt-infiltration and a wetness impregnation process, demonstrated an excellent catalytic performance for the high-temperature Fischer–Tropsch reaction.

Fischer–Tropsch synthesis of liquid hydrocarbons over mesoporous SBA-15 supported cobalt catalysts

The reducibility of Co/SBA-15 increased with increasing either Co loading or pore size of SBA-15 support. CO conversion increased with the increase of SBA-15 pore size. The Co/SBA-15 with larger Co crystallite size showed higher C₅₊ selectivity.

Fischer–Tropsch synthesis on Co/AlSBA-15: effects of hydrophilicity of supports on cobalt dispersion and product distributions

The increased C₂–C₄selectivity on the Co/AlSBA-15 was mainly attributed to the formation of small cobalt particles with a stronger metal–support interaction on the outer surface acid sites of the AlSBA-15 due to a higher hydrophilicity of the Al-incorporated SBA-15.

Comparative evaluation of the blends of gas-to-liquid (GTL) fuels and biodiesels with diesel at high idling conditions: an in-depth analysis on engine performance and environment pollutants

The effect of high-idling conditions at different engine performance-emission parameters were investigated using blends of GTL–diesel and biodiesel–diesel.

Direct synthesis of Co@Al-MCM-41 catalyst from conventional Co/SiO2 catalyst

A Co@Al-MCM-41 catalyst directly synthesized from Co/SiO₂ realized high selectivity of gasoline in Fischer–Tropsch synthesis with excellent stability due to suitable cobalt particle size and acidity of zeolite.

Catalytic performance of Co/Zn–Al2O3 Fischer–Tropsch catalysts: a comparative study of zinc introduction methodologies

Co-precipitated Zn–Al₂O₃ showed improved pore structure, and the supported catalyst presented the best FTS performance.