Cu promoted Ni-Co/hydrotalcite catalyst for improved hydrogen production in comparison with several modified Ni-based catalysts via steam reforming of ethanol

Abstract

Enhanced hydrogen production via catalytic steam reforming of ethanol has a huge potential. In the present investigation, several combinations of mixed metal oxide supported catalysts were evaluated for efficient and economical hydrogen generation from ethanol. The comparison was carried out in terms of ethanol conversion, hydrogen yield and cyclic stability over various catalyst-support systems. Several nickel based supported catalysts namely, Ni/MgO, Ni/Al₂O₃, Ni/CeO₂ and Ni/ZrO₂ were studied in this work among which Ni/MgO and Ni/Al₂O₃ showed satisfactory activity and stability for hydrogen production. Thereafter Ni/hydrotalcite (HTc)-type material was employed to combine features of the above catalysts which showed more than 90% ethanol conversion and yielded 82 mol% of hydrogen at optimized conditions. Finally, a novel combination of Cu promoted Ni-Co/HTc was synthesized and tested for improved hydrogen production. It showed almost complete conversion of ethanol (98.3%) with hydrogen yield of 83% at much lower temperature (673 K). The process conditions were optimized by studying effects of temperature, S/C ratio and GHSV on hydrogen production. Cu-Ni-Co/HTc also remained stable for up to 4 cycles justifying its multi-cycle activity, selectivity and durability. Such novel combination of catalyst-support system assists in improved hydrogen production in a sustainable manner.