Methanation of carbon dioxide on catalysts derived from amorphous Ni-Zr-rare earth element alloys

CO2 methanation of Ni catalysts supported on tetragonal ZrO2 doped with Ca2+ and Ni2+ ions

“…1a) at the reaction temperatures of 350 C or less, although the similar activities are obtained on the catalysts calcined at both temperatures when the reaction temperature is 400 C. The catalytic activities of the 50 at.% Ni-(Zr þ Ca) catalysts with suitable calcium contents and calcined at 650 C were compared with those of the 50 at.% Ni-50 at.% (Zr þ Sm) catalysts reported previously [11]. Obviously, the calcium-containing catalysts exhibit higher conversion in comparison with the samarium-containing catalysts at and above 300 C. In our previous investigations [7,10,11,16,17], Ni catalysts supported on tetragonal ZrO 2 with and without various additive elements were used for activity evaluation of CO 2 methanation. These catalysts were evaluated at low flow rates (3.0 and 5.4 L h À1 g À1 ), and the conversion reached the thermodynamic equilibrium one at and above 350 C. In the present study, in order to observe the difference of catalytic activity more explicitly, the activity evaluations were carried out at a high flow rate of 400 L h À1 g À1 .…”

“…Thus, we have successfully prepared Ni catalysts supported on tetragonal ZrO 2 by incorporation of Ni 2þ [7], and Y 3þ [17], Ce 3þ [17], Sm 3þ [11,16] or Ca 2þ together with Ni 2þ . When ZrO 2 is doped with these second and third elements, whose valences are lower than that of Zr 4þ , oxygen vacancies are introduced in the ZrO 2 lattice as well as the phase transition from monoclinic to tetragonal.…”

Methanation of Carbon Dioxide on Ni Catalysts on Mesoporous ZrO2 Doped with Rare Earth Oxides

“…They studied Ni/ZrO 2 catalysts modified with rare earth elements in the methanation of carbon dioxide, and found an improved activity on the Ni/(Zr-Sm)O x catalysts [1][2][3][4][5]. These catalysts were prepared either by the conventional wet impregnation method, or from amorphous nickel-samarium-alloys.…”

The production of renewable energy in the form of methane using electrolytic hydrogen generation

“…Gas Flow Rate 5.4 Lg -1 h -1 Figure 10 CO 2 conversion in CO 2 + 4H 2 on catalyst precursors of amorphous Ni-Zr-rare earth element alloys [16]. Amorphous alloy compositions are written in the figure in atomic percent.…”