Interaction among Metal Components of Zn鈥揗n鈥揅u-Based Sorbents Prepared by High-Pressure Impregnation Method and Its Effect on the Removal of H2S from Hot Coal Gas

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• 作者：Xianrong Zheng ; Weiren Bao ; Liping Chang ; Qingmai Jin ; Ruiyuan He ; Kechang Xie
• 刊名：Energy & Fuels
• 出版年：2012
• 出版时间：June 21, 2012
• 年：2012
• 卷：26
• 期：6
• 页码：3393-3398
• 全文大小：267K
• 年卷期：v.26,no.6(June 21, 2012)
• ISSN：1520-5029

文摘

A series of metal oxide sorbents for the deep removal of H₂S from hot coal gas were synthesized using a high-pressure impregnation method. Semicoke was selected as support and the solutions of one or more combination among zinc nitrate, manganese nitrate, and copper nitrate were selected as the active component precursors in the preparation process of sorbents. SEM results show that these metal oxides can be evenly dispersed onto semicoke support with nanometer particle sizes by a high-pressure impregnation method. Simultaneously, the pore structures of the sorbents are significantly improved through the hydrothermal process of high-pressure impregnation. The desulfurization activities of the Zn鈥揗n鈥揅u-based sorbents in a fixed-bed reactor under feeding gas of CO (33 vol %), H₂ (39 vol %), H₂S (500 ppmv), and N₂ (balance) are much better than those of single Zn-, Mn-, and Cu-based as well as double Zn鈥揗n-based sorbents prepared under the same operating conditions. The Z20M4C6SC sorbent can remove H₂S from 500 to 0.1 ppmv at 300鈥?50 掳C and hold for 56 h. The sulfur capacity is 13.84 g S/100 g sorbent at 500 掳C, which is higher than the simple summation of three single metal oxide sorbents. On the basis of the X-ray diffraction (XRD) results, ZnO, MnO₂, CuO, and ZnMnO₃ served as the active components of Zn鈥揗n鈥揅u-based sorbents. ZnMnO₃ played a main role in the removal of H₂S from hot coal gas. The addition of CuO in the Zn鈥揗n-based sorbent can improve the dispersion degree of active components on support and promote the formation of ZnMnO₃, thereby improving the desulfurization capacity of sorbent.