Synthesis gas production over highly active and stable nanostructured Ni-MgO-Al2O3 catalysts in dry reforming of methane: Effects of Ni contents

摘要

In this paper, CH4 reforming with CO2 was studied over Ni-MgO-Al2O3 catalysts with various Ni contents for the production of syngas (a mixture of H-2 and CO). Mesoporous nanocrystalline Ni-MgO-Al2O3 catalysts with the high specific surface area were prepared using a simple co-precipitation method. The samples were characterized by N-2 adsorption/desorption (BET), X-ray diffraction (XRD), temperature-programmed reduction and oxidation (TPR and TPO), and scanning electron microscopy (SEM) techniques. The prepared catalysts exhibited high catalytic performance (activity and stability) in dry reforming reaction. The obtained results indicated that the increase in nickel content increased both the reactant conversions and the amount of deposited carbon (whisker type carbon) on nickel catalysts. In addition, the effect of feed ratio was examined and the results showed that the increase in CO2/CH4 molar ratio from 0.5 to 3.0 increased the methane conversion and decreased the carbon dioxide conversion. With the increase of gas hourly space velocity (GHSV), the methane and carbon dioxide conversions decreased. (C) 2017 Elsevier Ltd. All rights reserved.