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The reverse water gas shift (RWGS) reaction converts carbon dioxide (CO2) and hydrogen (H2) to syngas, which is used to produce various high-added-value chemicals. This process has attracted great interest from researchers as a way of mitigating the potential environmental impacts of this greenhouse gas, with emphasis on global warming. This work aims to model and simulate an industrial catalytic reactor using kinetic data for the RWGS reaction. The simulation was carried out in Aspen Plus® v10. The thermodynamic analysis showed that the appropriate conditions for the reaction are feed molar ratio (H2/CO2) of 0.8:1, 750 °C, and 20 bar. The RWGS process proceeds in a multi-tubular fixed bed reactor with 36.26% CO2 conversion and 96.41% CO selectivity, at residence times in the order of 2.7 s. These results are at near-equilibrium CO2 conversion with higher CO selectivity.

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{'Reactants': ['Carbon dioxide, hydrogen'], 'Products': ['Syngas'], 'Method': ['Reverse Water Gas Shift (RWGS) reaction']}

The hydrogenation of carbon dioxide to light olefins is a direct and effective approach for achieving carbon neutrality. However, developing a tandem catalytic process involving methanol as an intermediate to achieve efficient directional conversion under mild conditions remains a challenge. Thus, we designed and constructed a bifunctional tandem catalyst, ZnZrOx/ZSM-5@n-ZrO2, where n represents the amorphous (am), monoclinic (m), and tetragonal (t) phases of ZrO2. The catalyst was prepared by coating an n-ZrO2 layer on the surface of ZSM-5 zeolite to form ZSM-5@n-ZrO2 with a coating structure, which was then ground and mixed with ZnZrOx to obtain the ZnZrOx/ZSM-5@n-ZrO2 tandem catalyst. At 340 °C and 2 MPa, the selectivity of the ZnZrOx/ZSM-5@t-ZrO2 catalyst toward light olefins reached 81.1%, with the carbon monoxide (CO) byproduct constituting only 34.3%. In contrast, the selectivity of ZnZrOx/ZSM-5 catalyst toward light olefins reached only 40.5% and a CO selectivity of 56.8%. Various characterizations and experimental results indicate that the ZSM-5@t-ZrO2 coating structure in the designed bifunctional catalyst effectively regulates the acid density and pore distribution of zeolite while inhibiting excessive hydrogenation of light olefins, ultimately achieving the desired mild transformation.

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{'Reactants': ['Carbon dioxide, Methanol '], 'Products': ['Light olefins, Carbon monoxide '], 'Method': ['Hydrogenation']}

Carbon dioxide methanation is a way of storing excess electrical energy as grid compatible gas. Spatially resolved channel plate reactor experiments were used to validate competing reactor (1D, 2Dx-z) models. Parallel exothermic carbon dioxide methanation and endothermic reverse water gas shift reactions were considered. The kinetic model, where the rate determining step is between an oxygenated complex (HCOO*) and an active site (*), was used in 2Dx-z CFD simulations for six laminar inflow conditions and variations in pressure, temperature, H2/CO2 ratio, methane, and steam co-feeds. The performance is improved by decreasing flowrate, and increasing H2/CO2 ratio, pressure, and temperature. Co-feeding methane has a negligible effect on reactor performance. However, co-feeding steam significantly reduces performance. At relatively high conversions, differential rates are obtained. This is due to the negligible dependence of the rate of carbon dioxide conversion with the equilibrium term of the reverse water gas shift reaction. With these studies, a link between the reaction mechanism and reactor performance is established at conditions relevant to power-to-gas applications.

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{'Reactants': ['Carbon dioxide, Hydrogen'], 'Products': ['Methane, Steam'], 'Method': ['methanation']}

Formate dehydrogenase (FDH, EC 1.17.1.9) belongs to the class of d -2‚Äëhydroxy acid dehydrogenases and is widely found in bacteria, archaea, yeast, fungi, plants and vertebrates. In recent years, the inverse reduction reaction of carbon dioxide to formate catalyzed by FDH has attracted widespread interest. However, the low catalytic activity has greatly limited its industrial application. In this work, three novel FDHs including FmFDH, KsFDH and SsFDH, were discovered. SsFDH showed relatively high catalytic activity toward CO2 conversion. The enzymological properties of the enzymes were characterized, and the catalytic mechanism of reducing CO2 to formate was investigated using bioinformatic and computational biochemical tools. The results of this work provide new insights into the function, structure and application of FDH in reducing CO2 to formate.

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{'Reactants': ['Carbon dioxide'], 'Products': ['Formate'], 'Method': ['Inverse reduction reaction']}

The carbon dioxide (CO2) hydrogenation to ethanol through chemical conversion is a significant branch of C1 chemistry research. It represents an ideal method for CO2 conversion and has garnered considerable attention for the last few years. Despite remarkable progress in thermal catalytic CO2 hydrogenation to ethanol, several challenges remain that require urgent attention. These include low conversion rates, low selectivity, and the formation of by-products during the hydrogenation process. To address these challenges, this study focuses on conducting a thermodynamic analysis of the CO2 hydrogenation process. It investigates the catalytic performance of both non-noble metals (Co, Cu, and Mo) and noble metals (Rh, Au, Pt, Pd, and Ir) as catalysts in CO2 hydrogenation. The effects of metal active sites on CO2 conversion and ethanol selectivity are thoroughly examined. The study also provides a comprehensive summary of the reaction conditions, including temperature, pressure, feed ratio, space velocity, reactor type, and the presence of water, in CO2 hydrogenation to ethanol. Furthermore, it explains the reaction mechanisms involved in different catalysts. Drawing upon the identified challenges in ethanol synthesis, the study summarizes strategies aimed at improving CO2 conversion and ethanol selectivity. These findings present a valuable theoretical foundation for catalyst design, optimization of reaction conditions, a deeper understanding of reaction mechanisms, and the potential industrial implementation of CO2 hydrogenation to ethanol.

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{'Reactants': ['Carbon dioxide, Hydrogen'], 'Products': ['Ethanol'], 'Method': ['hydrogenation']}

Owing to the necessity of carbon dioxide conversion and exploring new routes for ethylene and hydrogen production, carbon-dioxide-assisted dehydrogenation over alumina-supported catalysts is evaluated in the present contribution. In this regard, the experimental results of a wide range of catalysts at 700 °C and the GHSV of 3600 Lreactants/kgcatalyst.hr are presented and compared. The utilized catalysts showed activity toward the conversion of ethane. However, a few of them showed good selectivity for the production of either ethylene or hydrogen. The catalysts made up of the oxides of cobalt and molybdenum showed very good conversion, selectivity, and yield for ethylene production. Investigating the effect of time on steam on the catalyst performance indicated that these catalysts would be suitable choices in the course of ethylene production. 58% conversion of ethane and 21.9% ethylene yield are the achievements of utilizing the molybdenum-cobalt oxide catalyst. By utilizing rhenium-platinum nickel-potassium catalysts, 100% ethane conversion in tandem with more than 260.0% hydrogen yield was also obtained.

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{'Reactants': ['Ethane, carbon dioxide'], 'Products': ['Ethylene, hydrogen'], 'Method': ['Carbon-dioxide-assisted dehydrogenation ']}

Production of syngas from carbon dioxide (CO2) and water (H2O) is greatly attractive but very challenging for accomplishing tuneable/wide range of H2-to-CO ratios at current density. Herein, the anion-regulated self-supported Cu3Se2 with a hierarchical structure of nanosheet-assembled fibers, enabling multiple copper valence states and abundant in situ formed copper boundaries simultaneously regulating electrochemical CO2 reduction reaction (CO2RR) and H2 evolution reaction (HER). As a consequence, the delicate design of Cu3Se2 catalyst results in an outstanding electrocatalysis of syngas generation with a tuneable/wide range of H2-to-CO ratios (0.8 to 6.0), and high turnover frequency of 1303 h‚àí 1, which can achieve a high current density much higher than Cu foam and stable electrolysis with negligible attenuation of Faraday efficiency and current. The superior performance is attributed to the multiple copper valence states for activation of CO2, and the abundant boundaries for modifying the binding energy of intermediate for *COOH formation and *CO desorption and hydrogen adsorption for HER process. Therefore, the design of anion-regulated electrocatalysts with self-supported Cu3Se2 nanosheet-assembled fibers show great potential for the investigation of value-added chemicals/fuels from CO2RR.

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{'Reactants': ['Carbon dioxide, Water'], 'Products': ['Syngas'], 'Method': ['Electrocatalysis']}