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In this paper, the methanation of carbon oxides (CO and CO 2 ) was studied as an interesting way to provide a renewable energy source of synthetic natural gas (SNG) simultaneously reducing the emission of greenhouse gases. 15 wt.% Ni-based catalysts supported on CeO 2 , Al 2 O 3 and Y 2 O 3 oxides were synthesized by solution combustion synthesis. Then, a second series on Ni/Y 2 O 3 catalysts was prepared with different Ni loading (7-35 wt.%). The physicochemical properties of the catalysts were characterized by N 2 -physisorption, XRD, H 2 -TPR, CO-chemisorption, TEM, UV-Vis DRS, XPS, and CO 2 -TPD. The effect of reaction temperature (250-500°C) was investigated under atmospheric pressure, space velocity (GHSV) of 10,000 h −1 , and stoichiometric reactants ratio of (H 2 -CO 2 )/(CO+CO 2 ) = 3. A 200 h stability test was also carried out at 350°C over the 25 wt.% Ni/Y 2 O 3 catalyst. It can be concluded that the nature of Ni-support interactions played a crucial role in enhancing CO and CO 2 hydrogenation at relatively low reaction temperature. Ni/CeO 2 catalyst deactivated rapidly due to coke deposition, while the formation of NiAl 2 O 4 spinel was the main reason of the lower activity of the Al 2 O 3 -supported system. Activity data for Ni/Y 2 O 3 catalysts were closely related to the degree of Ni dispersion as well as to the medium-strength basicity. Good anti-coking and anti-sintering ability were observed after 200 h of lifetime test over the 25Ni/Y 2 O 3 catalyst.

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The effect of acid/base functional-groups associated with platinized-carbon electrodes on their catalytic activity toward electro-oxidation of methanol in sulfuric acid electrolyte at 60~ is studied. Platinized-carbon electrodes with small amounts of functional groups exhibit higher catalytic activity compared to those with large concentrations of acidic/basic surface functionalities. The overpotential for methanol oxidation is minimum on electrodes of platinized carbons with pHzpc values between 6 and 7. An x-ray photoelectron spectroscopic study of various platinized carbons suggests that the acid/base surface functional-groups produce ample amounts of surface Pt-oxides and a consequent decrease in activity toward methanol oxidation.