Removal of H2S from fuel gases at high temperatures using MnO/γ-Al2O3

doi:10.1016/0016-2361(95)92653-N

Fuel

Volume 74, Issue 2, February 1995, Pages 187-191

https://doi.org/10.1016/0016-2361(95)92653-N Get rights and content

Abstract

High temperature desulfurization of gases from coal gasification processes has important aspects for many industrial applications and electrical power generation plants. MnO, supported by γ-Al₂O₃(MnO/γ-Al₂O₃), was used as a regenerable sorbent for high temperature removal of H₂S from gases. The sorbent was prepared by wet impregnation and tested for successive sulfidation-regeneration cycles. Sulfidation was carried out at 600°C with an N₂/H₂/H₂S mixture containing 1.41–4.48% H₂S. Regeneration of the sorbent was performed with both N₂/H₂ and N₂/H₂/steam mixtures at the same temperature. The sorbent can be completely regenerated with a gas-steam mixture, while only 25-20% of the sulfur can be removed by physical (N₂/H₂) regeneration. The breakthrough and total capacities of the sorbent were found to be affected by the flow rate and the H₂S concentration of the gas. Consumption of steam for regeneration increased slowly until 60–70% of the regeneration was completed, and then rose rapidly. The manganese conversion ranged from 15–19% at the breakthrough point, to 32–35% at the end of sulfidation (acceptation).

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Citation Excerpt :
In recent years, Mn-based sorbents have attracted a considerable amount of research attentions not only due to their high sulfur capacity, high mechanical stability, and fast initial reaction rate for H2S removal in the range of 400–1000 °C, but also due to their reduction capability to MnO when the temperature is below 1200 °C [17–22]. A high temperature was beneficial for the S/O exchange rate of the manganese-based acceptor, and the sulfur capacity of the sorbent was proportional to the manganese content for H2S removal from high-temperature synthesis gas [23–29]. For achieving a more even distribution of active components with high manganese content (for high sulfur capacity), MnxOy/Al2O3 was prepared by different methods, such as repeated impregnation and co-precipitation methods [30–32].
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Full paperRemoval of H2S from fuel gases at high temperatures using MnO/γ-Al2O3

Abstract

Int. Eng. Chem.

Environ. Prog.

Chem. Eng. Prog.

Full paper
Removal of H₂S from fuel gases at high temperatures using MnO/γ-Al₂O₃