Ni-sepiolite and Ni-todorokite as efficient CO2 methanation catalysts: Mechanistic insight by operando DRIFTS

A Novel Method of 3D Printing High‐Loaded Oxide/H‐ZSM‐5 Catalyst Monoliths for Carbon Dioxide Reduction in Tandem with Propane Dehydrogenation

“…The vibrational modes at 1625 and 1440 cm −1 have been attributed to carbonates and bicarbonates, respectively. [ 32–35 ] Other vibrational modes cannot be assigned with complete confidence based on our literature review, but they are presumed to correspond with various carbonate and bicarbonate species. [ 32–35 ] Upon heating to 200 °C for desorption (Figure 2b), the bands at 2800, 1810, 1440, 1375, and 1200 cm −1 disappeared, signifying that the associated carbonate phases were weakly bound to the surface.…”

“…[ 32–35 ] Other vibrational modes cannot be assigned with complete confidence based on our literature review, but they are presumed to correspond with various carbonate and bicarbonate species. [ 32–35 ] Upon heating to 200 °C for desorption (Figure 2b), the bands at 2800, 1810, 1440, 1375, and 1200 cm −1 disappeared, signifying that the associated carbonate phases were weakly bound to the surface. However, a broad peak at 2125 cm −1 , which indicates CO bonds, and the sharp peaks at 1950 cm −1 and 1625 cm −1 , which signified CO and carbonate stretching, respectively, [ 32–35 ] remained present throughout the entire desorption step, indicating that they were strongly bound.…”

A Versatile Ambient‐to‐High‐Pressure Reaction Transmission Cell for in situ/operando Infrared Spectroscopic Investigations

“…Ni-sepiolite has been proved as efficient CO 2 methanation catalyst being essentially more active as a Ni/Al 2 O 3 reference catalyst. [27] Operando DRIFTS studies have shown a dissociative adsorption of CO 2 in the presence of H 2 , activated by dissociation into H atoms on Ni 0 particles. As a consequence, linearly and bridged bonded CO on Ni 0 were detected, while preferentially linearly bound CO was hydrogenated to methane.…”

“…As a consequence, linearly and bridged bonded CO on Ni 0 were detected, while preferentially linearly bound CO was hydrogenated to methane. [27] While DRIFT spectroscopy is advantageous for examining adsorbates on the surface, measurements performed in transmission mode are beneficial to monitor changes of gas composition (with detection of early reaction products) and adsorbate formation simultaneously. This is demonstrated in Figure 5 by comparing the respective DRIFT and FTIR spectra of 5Ni-Sep(P) measured under the same reaction conditions.…”

Low temperature conversion of levulinic acid into γ-valerolactone using Zn to generate hydrogen from water and nickel catalysts supported on sepiolite

“…One of these materials is sepiolite, which has been used as a catalytic support in many reactions. [26][27][28] Sepiolite is a hydrous magnesium silicate which presents many applications. Its main use is as absorbent, although it presents some other utilities such as pharmaceutical products, detergents, phytosanitary carriers, animal food.…”