CO Removal from Hydrogen Stream through Methanation on Ru/C Catalysts Doped with Lanthanum and Barium

Abstract

The influence of the lanthanum and barium addition on the physicochemical properties and catalytic behavior of the Ru/C catalyst for CO methanation was investigated. The catalyst was doped with La or with La plus Ba. It was found out that there are various ways the additives were applied in the study, thus changing the catalytic performance of the basic material and influencing the susceptibility of the carbon support in relation to undesired methanation. The highest catalytic activity, 23.46 (mmol CO/gC+Ru × h), was achieved for the LaRu/C system, with methane selectivity exceeding 80% over the whole temperature range. Ba addition caused a significant decrease in activity. TG-MS studies revealed that both La and Ba improved the resistance of the carbon support to undesired methanation. Detailed characterization methods, employing XRPD, Raman spectroscopy, CO chemisorption, and SEM-EDX, showed that the catalytic behavior of the studied catalysts was attributed to lanthanum distribution over the Ru/C materials surface and structural changes in the carbon support affecting electron supply to the metallic active phase.

Stability of Ruthenium/Carbon Catalytic Materials during Operation in Carbon Monoxide Methanation Process

“…Additionally, the effect of ruthenium loading in the sample was examined. It must be mentioned that the modified carbon support itself does not undergo hydrogenation to methane [44]. Figures 8 and 9 show the TG-MS profiles for the catalysts supported on C1 and C2 materials, respectively.…”

“…The disorder in the carbon supports structure was characterized in selected samples with Raman spectroscopy [44]. The powdered fresh materials and spent catalysts were characterized using a Renishaw inVia Qontor confocal Raman microscope.…”

“…The excitation wavelength was 532 nm from a 45 W laser with an 1800 nm −1 grating as the light source. The measurement detail parameters can be found in [44].…”