Sol-gel synthesis of nanocrystalline MgO and its application as support in Ni/MgO catalysts for ethanol steam reforming

Abstract

This work reports the improved catalytic activity of nickel catalysts supported on nanocrystalline magnesium oxide prepared by a sol–gel method, using Pluronic P123 as a structure-directing agent for pore formation. The presence of Pluronic also provided a reduction of the magnesium oxide crystallite size from 54 to 18 nm, as well as the attainment of small supported metallic nickel particles. In situ X-ray diffraction was used to assess the structural evolution of the materials during activation, followed by X-ray absorption spectroscopy, N2 physisorption isotherms, transmission electron microscopy, and temperature-programmed CO2 desorption. The materials synthesized with the surfactant presented heightened activity in the ethanol steam reforming reaction. The long-term stability of the catalysts was improved, due to the decrease the coke formation, with the catalyst prepared using surfactant developing less deactivating coke.