Hydrogen production with a microchannel heat-exchanger reactor by single stage water-gas shift; catalyst development

In this work Pt based mono and bimetallic catalysts were deposited into microchannel testing reactors and tested under conditions of water-gas shift (WGS). All the catalysts contained 25% of CeO2 and a metal loading of 2.5% or 5.0% (nominal wt.%). The bimetallic catalysts contained 2.5% Pt and 2.5% of Me where Me = Ni, Co, Mo, Pd, Fe, Re, Y, Cu or Zn. The feed gas composition amounted to 46.23% H2, 8.82% CO2, 7.94% CO and 37.02% H2O (vol.%). The tests were performed at reaction temperatures between 300 °C and 450 °C. 2.1Pt-2.1Re was identified as the catalyst formulation of highest activity. The composition and the preparation method of this catalyst were then modified for further activity and stability improvement. All the catalysts under investigation were characterized applying the following techniques: inductively coupled plasma atomic emission spectroscopy (ICP-AES), N2 physisorption, temperature programmed reduction (TPR), CO chemisorption, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The activity of the benchmark 3.6Pt catalyst was improved by the 2.1Pt-2.1Re catalyst and the stability of this catalyst was further improved by increasing slightly the nominal Pt content up to 3.33%. Therefore, a significant reduction of the Pt content compared to the benchmark 3.6Pt catalyst was achieved through the incorporation of Re.