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Kinetic Study on High-Temperature H₂S Removal over Mn-Based Regenerable Sorbent Using Deactivation Model.

ABSTRACT: The kinetics of high-temperature H₂S removal over Mn/Al sorbents prepared by co-precipitation method was investigated in a fixed-bed reactor using a deactivation model. The initial sorption rate constant (k ₀), deactivation rate constant (k _d), apparent activation energy (E _a), and deactivation energy (E _d) were obtained. The k ₀ and k _d values of Mn/Al sorbents are much higher than those of pure Mn₂O₃. This indicates that Mn/Al sorbents have higher reactivity on the removal of H₂S and less diffusion resistance caused by the formation of the sulfided product. The E _a and E _d values for the sorbent with the Mn content (wt %) of 35.4% are 38.18 and 31.05 kJ/mol, respectively. The deactivation model gives excellent predictions for the H₂S breakthrough curves in the sulfidation-regeneration process.

SUBMITTER: Wang J

PROVIDER: S-EPMC8792942 | biostudies-literature |

REPOSITORIES: biostudies-literature

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