Desulfurization performance of iron-manganese-based sorbent for hot coal gas

Abstract

A series of iron-manganese-based sorbents were prepared by co-precipitation and physical mixing method, and used for H₂S removal from hot coal gas. The sulfidation tests were carried out in a fixed-bed reactor with space velocity of 2000 h^-1(STP). The results show that the suitable addition of manganese oxide in iron-based sorbent can decrease H₂S and COS concentration in exit before breakthrough due to its simultaneous reaction capability with H₂S and COS. Fe₃O₄ and MnO are the initial active components in iron-manganese-based sorbent, and FeO and Fe are active components formed by reduction during sulfidation. The crystal phases of iron affect obviously their desulfurization capacity. The reducibility of sorbent changes with the content of MnO in sorbent. S7F3M and S3F7M have bigger sulfur capacities (32.68 and 32.30 gS/100 g total active component), while S5F5M has smaller sulfur capacity (21.92 gS/100 g total active component). S7F3M sorbent has stable sulfidation performance in three sulfidation-regeneration cycles and no apparent structure degradation. The sulfidation performance of iron- manganese-based sorbent is also related with its specific surface area and pore volume.

Keywords

iron-manganese-based sorbent / sulfidation performance / regeneration / hot coal gas

References

[1] Park N K, Lee D H, Jun J H, Lee J D, Ryu S O, Lee T J, Kim J C, Chang C H. Two-stage desulfurization process for hot gas ultra cleanup in IGCC. Fuel, 2006, 85(2): 227–234

[2] Fan H L, Li Y X, Li C H, Guo H X, Xie K C. The apparent kinetics of H₂S removal by zinc oxide in the presence of hydrogen. Fuel, 2002, 81(1): 91–96

[3] Fan H L, Xie K C, Shangguan J, Shen F, Li C H. Effect of calcium oxide additive on the performance of iron oxide sorbent for high-temperature coal gas desulfurization. Journal of Natural Gas Chemistry, 2007, 16(4): 404–408

[4] Chung J B, Chung J S. Desulfurization of H₂S using cobalt-containing sorbents at low temperatures. Chemical Engineering Science, 2005, 60(6): 1515–1523

[5] Jung S Y, Lee S J, Park J J, Lee S C, Jun H K, Lee T J, Ryu C K, Kim J C. Properties of nanosize zinc titanium desulfurization sorbents promoted with iron and cerium oxides. Industrial & Engineering Chemistry Research, 2008, 47(14): 4909–4916

[6] Polychronopoulou K, Galisteo F C, Granados M L, Fierro J L G, Bakas T, Efstathiou A M. Novel Fe-Mn-Zn-Ti-O mixed-metal oxides for the low-temperature removal of H₂S from gas streams in the presence of H₂, CO₂, and H₂O. Journal of Catalysis, 2005, 236(2): 205–220

[7] Pineda M, Palacios J M, Alonso L, García E, Moliner R. Performance of zinc oxide based sorbents for hot coal gas desulfurization in multicycle tests in a fixed-bed reactor. Fuel, 2000, 79(8): 885–895

[8] Jun H K, Koo J H, Lee T J, Ryu S O, Yi C K, Ryu C K, Kim J C. A study of Zn-Ti-based H₂S removal sorbents promoted with cobalt and nickel oxides. Energy & Fuels, 2004, 18(1): 41–48

[9] White J D, Groves F R Jr, Harrison D P. Elemental sulfur production during the regeneration of iron oxide high-temperature desulfurization sorbent. Catalysis Today, 1998, 40(1): 47–57

[10] Slimane R B, Abbasian J. Utilization of metal oxide-containing waste materials for hot coal gas desulfurization. Fuel Processing Technology, 2001, 70(2): 97–113

[11] Ko T H, Chu H, Lin H P, Peng C Y. Red soil as a regenerable sorbent for high temperature removal of hydrogen sulfide from coal gas. Journal of Hazardous Materials, 2006, 136(3): 776–783

[12] Pan Y G, Perales J F, Velo E, Puigjaner L. Kinetic behaviour of iron oxide sorbent in hot gas desulfurization. Fuel, 2005, 84(9): 1105–1109

[13] Ayala R E, Marshi D W. Characterization and long-range reactivity of zinc ferrite in high temperature desulfurization processes. Industrial & Engineering Chemistry Research, 1991, 30(1): 55–60

[14] Chang L P, Zhang Z Y, Ren X R, Li F, Xie K C. Study on the stability of sorbents removing H₂S from hot coal gas. Energy & Fuels, 2009, 23(2): 762–765

[15] Westmoreland P R, Harrison D P. Evaluation of candidate solids for high-temperature desulfurization of low-Btu gases. Environmental Science & Technology, 1976, 10(7): 659–661

[16] Wridzer J W, Kapteijn F, Moulijn J A. A high capacity manganese-based sorbent for regenerative high temperature desulfurization with direct sulfur production conceptual process application to coal gas cleaning. Chemical Engineering Journal, 2003, 96(1-3): 223–235

[17] Wakker J P, Gerritsen A W, Moulijn J A. High temperature H₂S and COS removal with MnO and FeO on γ-Al₂O₃ acceptor. Industrial & Engineering Chemistry Research, 1993, 32(1): 139–149

Acknowledgments

The authors gratefully acknowledge the financial support of the National Basic Research Program of China (2005CB221203), the National Natural Science Foundation of China (Grant No. 20976117), Shanxi Province Natural Science Foundation (2010011014-3) and Shanxi Province Basic Conditions Platform for Science and Technology Project (2010091015).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg