The kinetics of acetic acid steam reforming on Ni/Ca-Al2O3 catalyst. (5th October 2022) - Reeve, Jennifer
Abstract: As a significant by-product of many thermochemical and biological waste conversion processes, acetic acid (AcOH) is often investigated as model feedstock in the production of sustainable hydrogen from non-fossil sources. The kinetics of its steam reforming were extracted from packed bed reactor experiments over an industrially produced 14 wt% Ni/Ca-Al2 O3 catalyst at atmospheric pressure. The model consisting of AcOH steam reforming producing CO2 and H2, AcOH decomposition to CO and H2, and water gas shift, achieved the best fit, reflected in the lowest average relative errors (ARE) with experimental results, with ARE values below 5.4% and 6.4% on AcOH and water conversions respectively, and below 4% on H2 mol fraction. This model was validated away from equilibrium using additional experimental points, as well as for a wide range of equilibrium conditions with varying temperature (600–700 °C) and feed molar steam to carbon ratios (3–8) at atmospheric pressure using an independent method. Highlights: Kinetics of acetic acid (AcOH) steam reforming over Ni/Ca-Al2O3 catalyst. Negligible carbon deposition and no mass transfer limitations are demonstrated. Kinetic parameters derived for four models of 3–5 reactions fitted using gPROMS. Excellent fit obtained for model with SR AcOH, AcOH decomposition, and WGS. Validation for temperature (600–700 °C) and steam to carbon ratio (3–6) at 1 atm.