Sustainable syngas production from ethylene glycol reforming processes using Rh-based catalysts in microreactors

In this work the ethylene glycol (EG) as feed for syngas production by steam reforming (SR) and oxidative steam reforming (OSR) was studied applying microchannel testing reactors. The product composition was determined at a steam to carbon ratio (S/C) of 4.0, reaction temperatures between 625 °C and 725 °C and atmospheric pressure at volume hourly space velocities (VHSV) of the feed between 100 and 300 N L/(gcat h). Catalysts with different rhodium loading were prepared by two different preparation methods (conventional impregnation and separate nanoparticle synthesis) and compared with regard to their activity and selectivity. All the catalysts were characterized using the following techniques: N2 physisorption, temperature programmed reduction (TPR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Under all experimental conditions full conversion of ethylene glycol was achieved over the samples containing 2.5% and 5% Rh prepared by the impregnation method, equilibrium selectivity towards CO and CO2, lowest selectivity towards CH4 and lowest formation of by-products such as CH3CHO and C2 hydrocarbons. The other catalysts showed lower activity. The superior performance of the catalysts prepared by the impregnation method is supported by the measured higher rhodium dispersion of these samples.