CO2 methanation on Ru-doped ceria

Supported Catalysts for CO2 Methanation: A Review

“…At T = 450 • C, this catalyst converts 55% CO 2 with 99% selectivity to CH 4 . The reaction takes place on the reduced Ce 0.95 Ru 0.05 O 2 ; the role of Ru is to lower the reduction temperature with respect to pure ceria [63].…”

“…The equilibrium CO 2 conversion is reached at 340 • C. CO 2 -TPD profiles of Ni/CZ show weak and medium sites, different from Ni/Al 2 O 3 , which shows weak and strong basic sites; CO 2 adsorbed on strong basic sites cannot desorb from Ni/Al 2 O 3 surface until 700 • C. Consequently, the strongly adsorbed CO 2 on the surface does not participate in the reaction carried out from 220 • C to 400 • C. According to [166], CO 2 reacts with surface hydroxyls and surface oxygen to form hydrogen and monodentate carbonate, respectively [164,[166][167][168][169][170][171][172]. Formate species could be also important intermediates during the reaction [63,173,174]. Combining CO 2 -TPD and FTIR results, medium basic sites promote formation of monodentate formate and its hydrogenation during the CO 2 methanation, in accordance with [165,175].…”

“…The three mechanisms fall into two categories [222][223][224]: conversion of CO2 to CO prior to methanation involving a CO intermediate [225,226], and direct hydrogenation of CO2 to methane without the formation of CO as an intermediate [63,127,227,228]. DFT (Density Functional Theory) is used to describe semi-quantitatively the kinetics of catalytic reactions on the basis of thermochemistry and activation energies [214][215][216].…”

“…The three mechanisms fall into two categories [222][223][224]: conversion of CO 2 to CO prior to methanation involving a CO intermediate [225,226], and direct hydrogenation of CO 2 to methane without the formation of CO as an intermediate [63,127,227,228].…”

Activated Carbon-Supported Tetrapropylammonium Perruthenate Catalysts for Acetylene Hydrochlorination

“…Since the signal of Ru3d peak coincides with that of Cls peak, the Ru 3p3/2 XPS deconvolution spectrum is adopted to distinguish the different species ( Figure S4 and Table 3). For the fresh catalysts, there appear four kinds of Ru species including metallic Ru 0 at 461.6 eV, RuCl 3 at 463.4 eV, RuO 2 at 464.6 eV and RuO x at 466.1 eV in the original Ru/AC catalyst [35][36][37], and the relative content of them is 14.0%, 49.9%, 19.1%, and 17.0%, respectively. The TPAP/AC catalyst contains 11.3% Ru 0 , 42.5% RuCl 3 , 25.1% RuO 2 , and 21.1% RuO x .…”