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The oil and gas sector produces a considerable volume of greenhouse gas emissions, mainly generated from flaring and venting natural gas. Herein, a techno-economic analysis has been performed of a switchable catalytic process to convert the CH 4 and CO 2 in flared/vented natural gas into syngas or methanol. Specifically, it was shown that depending on greenhouse gas composition, dry methane reforming (DRM), reverse water-gas shift (RWGS), and CO 2 methanation could be chosen to valorise emissions in an overall profitable and flexible operation scenario. The switchable process produced methanol and synthetic natural gas as its products, resulting in an annual income of €687m and annual operating expenses of €452m. The pre-tax profit was calculated at €234m, and at the end of the project, the net present value was calculated as €1.9b with a profitability index of 4.7€/€. The expected payback time of this process was ca. 4 years, and with a 35% internal rate of return (IRR). Most importantly, this process consumed 42.8m tonnes of CO 2 annually. The sensitivity analysis revealed that variations in operation time, green hydrogen price, and products' prices significantly impacted the profitability of the process. Overall, this techno-economic analysis demonstrated that switchable catalysis in greenhouse gas utilisation processes is profitable, and thus it could play an important role in achieving net zero emissions. • A switchable CO 2 catalytic process that used flared/vented gas was investigated. • Methanol was produced via RWGS and DRM and natural gas via CO 2 methanation. • CO 2 consumption and profitability analyses were carried out. • The designed switchable catalytic plant was carbon negative. • The process was profitable, mainly due to the production of synthetic natural gas. [ABSTRACT FROM AUTHOR]

Methanol is a major fuel and chemical feedstock currently produced from syngas, a CO/CO2/H2 mixture. Herein we identify formate binding strength as a key parameter limiting the activity and stability of known catalysts for methanol synthesis in the presence of CO2. We present a molybdenum phosphide catalyst for CO and CO2 reduction to methanol, which through a weaker interaction with formate, can improve the activity and stability of methanol synthesis catalysts in a wide range of CO/CO2/H2 feeds. MoP‐ed up: MoP is a new catalyst for CO and CO2 hydrogenation to methanol. By stabilizing only the monodentate binding configuration of formate, the phosphide is able to circumvent the (scaling) relationship between the necessary ability of the catalyst to bind oxygen‐containing intermediates and catalyst deactivation resulting from high formate coverage in the presence of CO2. [ABSTRACT FROM AUTHOR]

Methanol is a major fuel and chemical feedstock currently produced from syngas, a CO/CO2/H2 mixture. Herein we identify formate binding strength as a key parameter limiting the activity and stability of known catalysts for methanol synthesis in the presence of CO2. We present a molybdenum phosphide catalyst for CO and CO2 reduction to methanol, which through a weaker interaction with formate, can improve the activity and stability of methanol synthesis catalysts in a wide range of CO/CO2/H2 feeds. MoP‐ed up: MoP is a new catalyst for CO and CO2 hydrogenation to methanol. By stabilizing only the monodentate binding configuration of formate, the phosphide is able to circumvent the (scaling) relationship between the necessary ability of the catalyst to bind oxygen‐containing intermediates and catalyst deactivation resulting from high formate coverage in the presence of CO2. [ABSTRACT FROM AUTHOR]

Molybdenum phosphide (MoP) catalyzes the hydrogenation of CO, CO2, and their mixtures to methanol, and it is investigated as a high-activity catalyst that overcomes deactivation issues (e.g., formate poisoning) faced by conventional transition metal catalysts. MoP as a new catalyst for hydrogenating CO2 to methanol is particularly appealing for the use of CO2 as chemical feedstock. Herein, we use a colloidal synthesis technique that connects the presence of MoP to the formation of methanol from CO2, regardless of the support being used. By conducting a systematic support study, we see that zirconia (ZrO2) has the striking ability to shift the selectivity towards methanol by increasing the rate of methanol conversion by two orders of magnitude compared to other supports, at a CO2 conversion of 1.4% and methanol selectivity of 55.4%. In situ X-ray Absorption Spectroscopy (XAS) and in situ X-ray Diffraction (XRD) indicate that under reaction conditions the catalyst is pure MoP in a partially crystalline phase. Results from Diffuse Reflectance Infrared Fourier Transform Spectroscopy coupled with Temperature Programmed Surface Reaction (DRIFTS-TPSR) point towards a highly reactive monodentate formate intermediate stabilized by the strong interaction of MoP and ZrO2. This study definitively shows that the presence of a MoP phase leads to methanol formation from CO2, regardless of support and that the formate intermediate on MoP governs methanol formation rate. [ABSTRACT FROM AUTHOR]

• Ni-Ga intermetallic catalysts for methanol synthesis from CO 2 were modified with Au, Cu and Co. • Au and Cu promote methanol synthesis activity. • Au-Ni-Ga demonstrates the highest activity. • Ni 3 Ga is the dominant intermetallic phase post catalysis. Ni-Ga and M-Ni-Ga (M = Au, Co, Cu) catalysts were evaluated for methanol synthesis from CO 2 at 10 bar and 200−270 °C. The following trend in turnover frequency (TOF) for CO 2 hydrogenation was observed: AuNiGa > CuNiGa > NiGa > CoNiGa, where TOF increased with decreasing catalyst affinity for CO. The presence of a third metal was found to influence both the formation of the Ni-Ga intermetallic phase as well as the number of available sites for CO chemisorption. Phase formation, catalyst composition and stability were evaluated using therm ogravimetric analysis (TGA), X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning transmission electron microscopy and energy dispersive X-ray spectroscopy (STEM-EDX). Au-Ni-Ga, which showed a nearly 4-fold improvement in TOF at 263 °C and 10 bar compared to Ni-Ga, consisted of Ni 3 Ga particles decorated with Au, as evidenced by post catalysis characterization. [ABSTRACT FROM AUTHOR]

• An air exposed Ni 5 Ga 3 catalyst was investigated for CO 2 hydrogenation to methanol. • Upon air exposure a surface Ga oxide shell forms. • In-situ studies reveal complete reduction of the Ga oxide only at high temperatures. • The surface oxidized Ni 5 Ga 3 is more active compared to a fully reduced Ni 5 Ga 3 catalyst. • Surface amorphous Ga 2 O 3 promotes methanol synthesis. A δ -Ni 5 Ga 3 /SiO 2 catalyst, which is highly active and stable for thermal CO 2 hydrogenation to methanol, was investigated to understand its surface dynamics during reaction conditions. The catalyst was prepared, tested and characterized using a multitude of techniques, including ex-situ XRD (X-ray Diffraction), TEM (Transmission Electron Microscopy), H 2 -TPR (Temperature Programmed Reduction), CO chemisorption, along with in-situ ETEM (Environmental Transmission Electron Microscopy), APXPS (Ambient Pressure X-ray Photoelectron Spectroscopy) and HERFD-XAS (High Energy Resolution Fluorescence Detected X-Ray Absorption Spectroscopy). Upon air exposure Ga migrates from the subsurface region to the surface of the nanoparticles forming a Ga-oxide shell surrounding a metallic core. The oxide shell can be reduced completely only at high temperatures (above 600 °C); the temperature of the reducing activation treatment plays a crucial role on the catalytic activity. HERFD-XAS and APXPS measurements show that an amorphous Ga 2 O 3 shell persists during catalysis after low temperature reductions, promoting methanol synthesis. [ABSTRACT FROM AUTHOR]