Zirconia and alumina based catalysts for steam reforming of naphthalene

The present paper deals with experimentation of ZrO2 and Al2O3-supported catalysts for conversion of naphthalene, chosen as tar model compound of pyrolysis or gasification syngas. In particular, the reforming capacity of active metals and promoters such as Co, Ni, Fe, Cr, Ce and Pt was tested in a fixed bed reactor at temperature from 400 to 900 degrees C. As regards ZrO2-supported catalysts, the best results were achieved by the Ni/Fe/Pt catalyst with 96% naphthalene conversion, 78% and 280% as CO and H-2 production yield at 800 degrees C. Regarding Al2O3-supported catalysts, they were more active on average than the zirconia ones, achieving a very good performance even at 500 degrees C (90-100% naphthalene conversion, 30-40% CO yield and 300-350% H-2 yield at 550 degrees C). Influence of different amounts of alumina, montmorillonite and carbon on carrier composition as well as pellets' size were also studied. Both zirconia and alumina catalysts showed deactivation at higher temperatures due to coke deposition, resulting in a strong H-2 production drop. Regeneration of catalysts by O-2 and steam as well as activation by H-2 were also studied. The activated catalyst was able to convert more than 99% naphthalene at 450 degrees C with a CO and H-2 production yield of 26% and 420%, respectively. (C) 2012 Elsevier Ltd. All rights reserved