Methane reforming in steam (SR), auto-thermal (ATR) and partial oxidation (PDX) conditions over Ni/Ba-Ce-0.9-Y-0.1 catalyst was investigated in the temperature range 500-700 degrees C. Catalyst presents a satisfying activity in PDX condition only. BCY carrier was not stable in the presence of CO2 and, irrespective of reaction conditions, it reacts with CO2 giving rise to the formation of BaCO3 and CeO2. The very low activity observed in SR conditions was due to the negative role exerted by water strongly absorbed on catalyst surface, limiting so the accessibility and reduction state of Ni active sites. In PDX condition catalyst is active and satisfying H-2 yield can be reached by operating at T = 700 degrees C. A significant reduction of coke formation was observed by operating in PDX at 700 degrees C. On the contrary, in ATR condition at the same reaction temperature huge amount of filamentous coke was observed. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.