Study on the carbon deposition in steam reforming of ethanol over Co/CeO2 catalyst

In this work, coke formation over Co/CeO2 Catalysts for the steam reforming of ethanol was studied. Variations of ethanol conversion and product distribution with reaction temperature and time were investigated and the used catalysts were characterized with thermal analysis method and transmission electron microscopy. The results indicate that the reaction temperature exerts influences on coke formation and its property significantly. As the reaction temperature is 450 degrees C or lower, catalyst particles are heavily enclosed by cokes, leading to severe deactivation. As the reaction temperature is 500 degrees C or 550 degrees C, the encapsulation of catalyst particles is rarely observed due to the formation of another kind of carbon, namely, tube- or fiber-like carbon, which results in mild deactivation. When the reaction temperature is over 600 degrees C, carbon deposition is not a major problem for the steam reforming of ethanol over Co/CeO2 catalysts, for carbon deposition or coke formation under these temperatures is not notable. (C) 2008 Elsevier B.V. All rights reserved.