Sulfation behavior of CuO/γ-Al2O3 sorbent for the removal of SO2 from flue gas

CuO/γ-Al2O3 has been considered as a promising and recycling sorbent to remove sulfur dioxide from flue gas. In this study, a series of CuO/γ-Al2O3 sorbents with different CuO loadings were prepared by impregnation. The monolayer coverage of CuO supported on γ-Al2O3 determined by X-ray quantitative analysis was 0.275 g CuO/g (γ-Al2O3). Below the monolayer coverage, CuO was found highly dispersed on γ-Al2O3. Thermogravimetric technique was used to study sulfation kinetics and sulfation recycling. It was found that the Langmuir kinetic adsorption model described well the experimental data at the rapid sulfation region of the CuO/γ-Al2O3 sorbent. The adsorption activation energy was 19.98 kJ/mol and the pre-exponential factor was 9.97×10−5 s−1 · Pa−1. The CuO/γ-Al2O3 sorbent has shown good performance on regeneration, but long sulfation time might cause the deactivation of the CuO/γ-Al2O3 sorbent. It was also seen that the sulfated γ-Al2O3 support could not be reduced at 400°C.