Elucidating the Reaction Kinetics of Hydrogen Generation via Ethanol Steam Reforming Using a Nickel-based Catalyst

Abstract

The continuous rise in CO2 emissions from fossil fuel consumption has intensified the search for alternative clean energy sources. Hydrogen produced from renewable sources like ethanol offers a promising alternative to fossil fuels, mitigating CO2 emissions. This study investigates the kinetics of hydrogen production via ethanol steam reforming using a nickel-based catalyst, specifically the Ar-401catalyst. Characterization techniques including SEM-EDX, TEM, BET, TPR and PXRD were used to analyze the catalysts properties. Under optimal conditions of 973 K, atmospheric pressure, and a steam-to-ethanol ratio of 9, we achieved 100% ethanol conversion, 74.8% hydrogen selectivity, and 85% hydrogen yield. Kinetic experiments were conducted under kinetically controlled conditions, examining the effects of temperature (473 K - 673 K) and weight hourly space velocity ranging from 1-15 (g·h/mol). A power law kinetic model was developed, yielding an activation energy of 11.17 kJ/mol and a reaction order of 0.46, with an absolute average deviation of 3.23% between predicted and experimental rates. This study provides key insights into the reaction mechanisms and highlights the effectiveness of the nickel-based catalyst, providing valuable insights for the design of efficient chemical reactors for sustainable hydrogen production.