Kinetic Study on the Sulfidation and Regeneration of Manganese-Based Regenerable Sorbent for High Temperature H2S Removal

This paper describes a kinetic study on the sulfidation and regeneration of Mn/Al 2 O 3 sorbent for high temperature H 2 S removal. The influence of the reactant gas compositions and temperatures on the sulfidation and regeneration behavior was systematically investigated in a thermogravimetric apparatus. The results show that the shrinking core model can be used to correlate with the experimental data. The sulfidation is mainly dominated by diffusion. Through the regressions of the initial sulfidation reaction data, the chemical reaction order, activation energy, and pre-exponential factor are 1, 37.42 kJ/mol, and 4.16 × 10 –2 m/s, respectively, and the diffusion activation energy and pre-exponential factor are 57.23 kJ/mol and 6.41 × 10 –5 m 2 /s, respectively. O 2 regeneration has the same situation as sulfidation; the chemical reaction order, activation energy, and pre-exponential factor are 1, 24.62 kJ/mol, and 0.17 m/s, respectively, and the diffusion activation energy and pre-exponential factor are 122.44 kJ/mol and 8.51 × 10 –4 m 2 /s, respectively. For SO 2 regeneration, the regeneration rate is controlled by the chemical reaction in the early stage, and then it is controlled by the diffusion in the latter stage; the chemical reaction order, activation energy, and pre-exponential factor are 1, 124.82 kJ/mol, and l.62 × 10 2 m/s, respectively, and the diffusion activation energy and pre-exponential factor are 224.83 kJ/mol and 2.33 × 10 –6 m –2 /s, respectively.