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Our latest work using multi-length scale chemical tomography to study fixed bed reactors during the oxidative coupling of methane reaction

Graphical abstractOur latest work using multi-length scale chemical tomography to study fixed bed reactors during the oxidative coupling of methane reaction has just been published at the Journal of Catalysis. “Real-time multi-length scale chemical tomography of fixed bed reactors during the oxidative coupling of methane reaction” is a result of a collaboration between scientists at UCL, Finden, ESRF, Diamond Light Source, Research Complex at Harwell, ISIS Neutron and Muon Source, University of Manchester, Boreskov Institute of Catalysis SB RAS and VITO.

In this work, we present the results from multi-length-scale studies of a Mn-Na-W/SiO2 and a La-promoted Mn-Na-W/SiO2 catalyst during the oxidative coupling of methane reaction. The catalysts were investigated from the reactor level (mm scale) down to the single catalyst particle level (μm scale) with different synchrotron X-ray chemical computed tomography techniques (multi-modal chemical CT experiments). These operando spatially-resolved studies performed with XRD-CT (catalytic reactor) and multi-modal μ-XRF/XRD/absorption CT (single catalyst particle) revealed the multiple roles of the La promoter and how it provides the enhancement in catalyst performance. It is also shown that non-crystalline Mn species are part of the active catalyst component rather than crystalline Mn2O3/Mn7SiO12 or MnWO4.

The paper can be found in Journal of Catalysis, Volume 386, June 2020, Pages 39-52. DOI: https://doi.org/10.1016/j.jcat.2020.03.027

New paper on the stability of Na-Mn-W/SiO2 catalyst for the OCM has now been accepted at the Faraday Discussions!

A new paper by our former PhD student Dorota Matras and partners from MEMERE project has been accepted in the Faraday Discussions.

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 reaction. 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 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.

Read the full paper at https://doi.org/10.1039/C9FD00142E