abstract

• Titanate nanotubes (TiNT) were synthesized by the hydrothermal method and used as a support for Rh (Rh/TiNT) and Ru nanoparticles (Ru/TiNT). Both catalysts were found active in the gas-phase hydrocarboxylation of methanol with CO2 and H2 as reactants and methyl iodide as a promoter at 1 bar and 150 °C to produce methyl acetate (MA), the Rh/TiNT catalyst being more active in the reaction with a reaction rate of 0.698 molMA molRh−1 h−1 compared with 0.272 molMA molRu−1 h−1 for the Ru/TiNT catalyst. The structural, textural, and compositional properties of the supported metal catalysts were evaluated by N2 physisorption, X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). Results of XRD and Raman spectroscopy demonstrated that TiNT consisted of a unique crystalline structure of trititanate (Na2Ti3O7), while the results of TEM confirmed the multilayer nanotubular morphology with an internal diameter of ∼3 nm. Also, the TEM analysis of Rh/TiNT and Ru/TiNT samples revealed small (∼1 nm) and highly dispersed metal particles. Infrared spectroscopy studies performed under reaction conditions allowed the identification of important surface species; in particular, Rh-acetyl species were proposed as key reaction intermediates. This work shows an interesting and promising heterogeneous route for the valorization of CO2 to produce a value-added compound under moderate conditions. © 2023 The Royal Society of Chemistry.

authors

• De Haro Del Río D.A.
• Flores-Escamilla G.A.
• Handy Vogel Brent Edward
• Ojeda-Galván H.J.
• Santos-Lõpez I.A.

publication date

• 2022-01-01

funding provided via

• Consejo Nacional de Ciencia y Tecnología, CONACYT: CB-2015-1-253403; Universidad Autónoma de Nuevo León, UANL: PAICYT-IT1685-21; Instituto Potosino de Investigación Científica y Tecnológica, IPICyT  Grant

published in

• Catalysis Science and Technology  Journal

keywords

• Carbon dioxide; Catalyst supports; High resolution transmission electron microscopy; Infrared spectroscopy; Methanol; Morphology; Nanocatalysts; Nanoparticles; Nanotubes; Reaction intermediates; Rhodium compounds; Ruthenium compounds; Synthesis (chemical); X ray diffraction; Hydrocarboxylation; Infrared: spectroscopy; Methyl acetates; Rhodium nanoparticles; Ruthenium Nanoparticles; Synthesised; Titanate nanotube catalysts; Titanate nanotubes; X- ray diffractions; ] catalyst; Raman spectroscopy
• Carbon dioxide; Catalyst supports; High resolution transmission electron microscopy; Infrared spectroscopy; Methanol; Morphology; Nanocatalysts; Nanoparticles; Nanotubes; Reaction intermediates; Rhodium compounds; Ruthenium compounds; Synthesis (chemical); X ray diffraction; Hydrocarboxylation; Infrared: spectroscopy; Methyl acetates; Rhodium nanoparticles; Ruthenium Nanoparticles; Synthesised; Titanate nanotube catalysts; Titanate nanotubes; X- ray diffractions; ]+ catalyst; Raman spectroscopy

Digital Object Identifier (DOI)

• 10.1039/d2cy01396g

PubMed ID

start page

• 726

end page

• 736

volume

• 13

issue

• 3