Steam reforming of acetic acid over Ni–Ba/Al2O3 catalysts: Impacts of barium addition on coking behaviors and formation of reaction intermediates

Effect of the Addition of Alkaline Earth and Lanthanide Metals for the Modification of the Alumina Support in Ni and Ru Catalysts in CO2 Methanation

“…In combination with nickel, the greatest contribution in the TPR profile corresponds to the reduction of nickel species (with reduction peaks at 583, 903, and 1053 K), being facilitated the interaction of Ni and alumina by the presence of Ba. The contribution of Ba was mainly observed in the increase of the first two catalyst reduction peaks and decrease in the third, due to the interaction of BaO with the support, forming other structures (as spinel) [53]. The experimental profile presented three peaks and one shoulder at 498, 650, 682, and 561 K, respectively, as the literature shows [28,53].…”

“…The contribution of Ba was mainly observed in the increase of the first two catalyst reduction peaks and decrease in the third, due to the interaction of BaO with the support, forming other structures (as spinel) [53]. The experimental profile presented three peaks and one shoulder at 498, 650, 682, and 561 K, respectively, as the literature shows [28,53]. The contribution of Ca is due to the presence of CaO in the catalyst, which is related to reduction at low temperatures, strengthening the interaction with NiO and improving the reducibility of Ni [28].…”

Ru–Ni bimetallic catalysts for steam reforming of xylene: effects of active metals and calcination temperature of the support

“… 6 However, the acid sites on the alumina support accelerate the dehydration reactions forming the undesirable coke, thus the support is usually modified by other oxides. The loading of alkaline oxides such as MgO, BaO, and CaO can neutralize the acid sites and inhibit the coke formation, 23–26 while strong alkalinity induced by Na or Mg will also decrease the catalytic performance by forming some oxygen-containing species. 27 The loading of oxides with oxygen storage capacity and facile redox properties such as CeO 2 can facilitate the removal of coke owing to their mobile lattice oxygen.…”

Ethanol Steam Reforming for Hydrogen Production Over Hierarchical Macroporous Mesoporous SBA-15 Supported Nickel Nanoparticles

“…Alkali metal or alkali earth metal promotors switch-off ethanol dehydration and ethylene polymerisation, through tuning of the acid/base nature [7], in contrast acidic supports, such as zeolites, enhance ethanol dehydration the formation of ethylene increase coking and deactivation [6]. Basic oxides of Ca and Mg have been used to increase H 2 production performance via sorptionenhance steam reforming [8,9], praseodymium and barium oxides have also promoted enhance steam reforming activity through reduced Ni sintering [10,11], whereas rare earth and transition metal oxides, e.g. CeO 2 or ZrO 2 , impart labile surface oxygen which assists oxidation of carbon deposits to CO 2 [12].…”