Degradation of MO and H2O2 on Cu/γ‐Al2O3 pellets in a fixed bed reactor: Kinetics and transport characteristics

Abstract

AbstractPelletized Cu catalysts (Cu/γ‐Al2O3) with different diameters (dp = 1.1–4.2 mm) were prepared and examined kinetically for methyl orange (MO) degradation using a fixed bed reactor. A Cu/γ‐Al2O3 catalyst (dp = 2.3 mm) exhibited high degradation activity (Conv.MO > 95%) and superior leaching resistance (Cu leaching <0.6 mg/L in 200 hr). Apparent kinetics showed that both MO degradation and H2O2 decomposition were mainly controlled by internal mass transfer. A plug‐flow reactor model with mass‐transfer coefficients was developed, and a modified empirical correlation for external mass transfer (Sh = 1.5Re'1.10Sc0.42) was proposed to accurately describe the species transport from/to the catalyst pellets in the low Reynolds number regime. The model was verified against conversions of pollutants degradation and H2O2 decomposition separately in a fixed bed with relative errors <5% compared with experimental data; thus, it could be used as an effective tool for further design and optimization of reactor configuration and reaction conditions for the continuous catalytic wet peroxide oxidation process.