Sorption enhanced steam reforming of ethanol on Ni-CaO-Al₂O ₃ multifunctional catalysts derived from hydrotalcite-like compounds

This paper describes the sorption of carbon dioxide for enhanced steam reforming of ethanol to produce hydrogen via Ni-CaO-Al₂O₃ multifunctional catalysts derived from hydrotalcite-like compounds (HTlcs). The catalysts were characterized by N₂ adsorption-desorption, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), H₂ temperature-programmed reduction (H₂-TPR) and thermogravimetric analysis (TGA) and tested in sorption enhanced steam reforming of ethanol (SESRE), in which products were monitored by an online mass spectrometer (MS). The Ni-CaO-Al₂O₃ catalysts possess uniform distribution of Ni, Ca and Al, contributing significantly to the excellent CO₂ adsorbent capacity and reforming activity in SESRE. We have also examined the effect of Ca/Al ratios on Ni dispersion, CaO particle size, and catalytic reactivity; a Ca/Al of 3.0 was optimized. The Ni-CaO-Al₂O₃ catalysts outperform the conventional mixture of CaO adsorbents and Ni/Al ₂O₃ catalysts for SESRE.