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Ordered mesoporous “one-pot” synthesized Ni-Mg(Ca)-Al2O3 as effective and remarkably stable catalysts for combined steam and dry reforming of methane (CSDRM)

“…9 to 11) to produce the expected gaseous CO and H 2 compounds. By facilitating H 2 O and CO 2 dissociation [26,30,37], basicity enhances the formation of surface activated O* that can then react with neighbour adsorbed C*, thus inhibiting (or reducing) the participation of the latters to carbon polymerization phenomena that otherwise take place leading to coke [80]. In view of the high carbon contents in the spent Ni x% Al 2 O 3 series of samples (Table 5), such coke deposits are formed at a significant extent in the less basic alumina-based materials (with no additives).…”

“…However, the stability of supported Ni-based catalysts under the harsh reaction conditions of CSDRM [20][21][22][23] is still an important concern. The major deactivation drawbacks are severe coke deposition, reoxidation and thermal agglomeration of the Ni 0 nanoparticles under steam and at high temperature [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39].…”

“…It is commonly accepted that basic modifiers (e.g. MgO) in the catalyst formulation promotes CO 2 adsorption/activation on the surface and its subsequent reaction with neighbour carbon C (s) deposits, leading globally to CO production (CO 2 + C (s) → 2CO) [26,30,37]. Likewise, the addition of active oxygen carriers such as CeO 2 and/or ZrO 2 within Ni-based catalysts (Table 1) is known to result in oxidative removal of C (s) deposits via their combustion with surface oxygen giving CO 2 [32,34,35].…”

“…ii) subsequent calcination after Ni and/or co-element impregnation [3][4][5][24][25][26][28][29][30][32][33][34][35][36][37][38][39] and iii) eventually high temperature steam treatment (H 2 /H 2 O) following a H 2 reduction session [25].…”

Organolithium complex as a gas sensing material for oxides from ab initio calculations and molecular dynamics simulations

“…Adsorption of maximum number of CO and CO 2 molecule on Li metal surface can be useful for the study of catalytic oxidation of CO molecule and hydrogenation of CO . These reactions play an important role in syngas production, water–gas shift production and Fischer–Tropsch process . Similar to single molecule adsorption case, after adsorption of maximum number of gas molecules on C 2 H 4 Li complex also, the CC bond length gets shortned whereas the CLi bond gets elongated.…”