Direct use of as-synthesized multi-walled carbon nanotubes for carbon dioxide reforming of methane for producing synthesis gas

In this study, laboratory prepared multi-walled carbon nanotubes (MWCNTs) over Co-Mo/MgO catalysts were used as novel nanocomposite catalysts for carbon dioxide reforming of methane (CRM). The influence of acid treatment process on the catalyst performance was thoroughly investigated. It was determined that Co-Mo/MgO present in the as-synthesized MWCNTs was responsible for high catalytic activity of the reforming reaction. The performance of the nanocomposite catalysts was compared with the conventional Co-Mo/MgO catalysts prepared by sol-gel method, revealing that MWCNTs played a supporting role in preventing catalyst deactivation. The nanocomposite catalysts gave CH4 and CO2 conversions of 97% and 98%, respectively, for the CRM reactions performed at 850 degrees C with a GHSV of 120 L/h g(cat) and a CH4/CO2 ratio of 1 under atmospheric pressure. Stability tests, carbon deposition and characteristics of the nanocomposite catalysts were investigated up to 100 h of reaction. The proposed reaction mechanism for this catalyst shows that CH4 decomposition and carbon gasification by CO2 were the two important side-reactions. (C) 2014 Elsevier B.V. All rights reserved.