Biogas as a Renewable Feedstock for Green Ethylene Production via Oxidative Coupling of Methane: Preliminary Feasibility Study

A preliminary feasibility study for the use of biogas as feedstock for the oxidative coupling of methane process aiming at green ethylene production is carried out. An economic assessment is performed based on literature, market and process simulation data, with the uncertainties being considered through Monte Carlo simulations. It is shown that the proposed process is economically interesting under a wide range of scenarios. The challenges and opportunities for the implementation of the process are highlighted to guide further studies.DFG, 53182490, EXC 314: Unifying Concepts in Catalysi

Multi‐scale studies of 3d printed Mn–Na–W/SiO2 catalyst for oxidative coupling of methane

This work presents multi‐scale approaches to investigate 3D printed structured Mn–Na– W/SiO2 catalysts used for the oxidative coupling of methane (OCM) reaction. The performance of the 3D printed catalysts has been compared to their conventional analogues, packed beds of pellets and powder. The physicochemical properties of the 3D printed catalysts were investigated using scanning electron microscopy, nitrogen adsorption and X‐ray diffraction (XRD). Performance and durability tests of the 3D printed catalysts were conducted in the laboratory and in a miniplant under real reaction conditions. In addition, synchrotron‐based X‐ray diffraction computed tomog-raphy technique (XRD‐CT) was employed to obtain cross sectional maps at three different positions selected within the 3D printed catalyst body during the OCM reaction. The maps revealed the evo-lution of catalyst active phases and silica support on spatial and temporal scales within the interiors of the 3D printed catalyst under operating conditions. These results were accompanied with SEM‐ EDS analysis that indicated a homogeneous distribution of the active catalyst particles across the silica support

Effect of thermal treatment on the stability of Na–Mn–W/SiO2 catalyst for the oxidative coupling of methane

In this study, we investigate the effect of thermal treatment/calcination on the stability and activity of a Na-Mn-W/SiO2 catalyst for the oxidative coupling of methane. The catalyst performance and characterisation measurements suggest that the W species are directly involved in the catalyst active site responsible for CH4 conversion. Under operating conditions, the active components, present in the form of a Na-W-O-Mn molten state, are highly mobile and volatile. By varying the parameters of the calcination protocol, it was shown that these molten components can be partially stabilised, resulting in a catalyst with lower activity (due to loss of surface area) but higher stability even for long duration OCM reaction experiments

Multi-Scale Studies of 3D Printed Mn–Na–W/SiO2 Catalyst for Oxidative Coupling of Methane

This work presents multi-scale approaches to investigate 3D printed structured Mn–Na–W/SiO2 catalysts used for the oxidative coupling of methane (OCM) reaction. The performance of the 3D printed catalysts has been compared to their conventional analogues, packed beds of pellets and powder. The physicochemical properties of the 3D printed catalysts were investigated using scanning electron microscopy, nitrogen adsorption and X-ray diffraction (XRD). Performance and durability tests of the 3D printed catalysts were conducted in the laboratory and in a miniplant under real reaction conditions. In addition, synchrotron-based X-ray diffraction computed tomography technique (XRD-CT) was employed to obtain cross sectional maps at three different positions selected within the 3D printed catalyst body during the OCM reaction. The maps revealed the evolution of catalyst active phases and silica support on spatial and temporal scales within the interiors of the 3D printed catalyst under operating conditions. These results were accompanied with SEM-EDS analysis that indicated a homogeneous distribution of the active catalyst particles across the silica support

Multi-Scale Studies of 3D Printed Mn−Na−W/SiO2 Catalyst for Oxidative Coupling of Methane

This work presents multi-scale approaches to investigate 3D printed structured Mn–Na–W/SiO2 catalysts used for the oxidative coupling of methane (OCM) reaction. The performance of the 3D printed catalysts has been compared to their conventional analogues, packed beds of pellets and powder. The physicochemical properties of the 3D printed catalysts were investigated using scanning electron microscopy, nitrogen adsorption and X-ray diffraction (XRD). Performance and durability tests of the 3D printed catalysts were conducted in the laboratory and in a miniplant under real reaction conditions. In addition, synchrotron-based X-ray diffraction computed tomography technique (XRD-CT) was employed to obtain cross sectional maps at three different positions selected within the 3D printed catalyst body during the OCM reaction. The maps revealed the evolution of catalyst active phases and silica support on spatial and temporal scales within the interiors of the 3D printed catalyst under operating conditions. These results were accompanied with SEM-EDS analysis that indicated a homogeneous distribution of the active catalyst particles across the silica support.EC/H2020/679933/EU/MEthane activation via integrated MEmbrane REactors/MEMEREDFG, 414044773, Open Access Publizieren 2021 - 2022 / Technische Universität Berli

Real-Time <i>Operando</i> Diffraction Imaging of La–Sr/CaO During the Oxidative Coupling of Methane

An La–Sr/CaO catalyst has been chemically imaged during activation and under <i>operando</i> conditions during the oxidative coupling of methane reaction (OCM) at high temperature using X-ray diffraction computed tomography (XRD-CT) in combination with full pattern Rietveld refinement. At room temperature the main components of the catalyst were present as carbonates and hydroxides. During the activation stage (temperature ramp) they decomposed, forming La₂O₃, SrO, and mixed CaO–SrO oxides. Under the OCM reaction conditions, the predominant phases present were (∼20% wt) La₂O₃ and CaO-SrO (∼45% wt), and these remained stable throughout the entire reaction, whereas SrO, formed during activation, reacted with produced CO₂ leading to formation of SrCO₃ (∼35% wt). Two polymorphs of SrCO₃, orthorhombic and rhombohedral, were found to be stable under reaction conditions although the extent to which these phases were observed varied spatially and temporally with reactant gas composition. The presence of the high temperature rhombohedral polymorph can be associated with higher combustion activity, and since the Rietveld analysis is performed on a pixel-by-pixel basis, it is possible to observe, for the first time, domains of differing activity within the reactor