Abstract A hierarchical porous carbon sorbent was fabricated by pyrolysis of rice straw in the presence of nanoscale CaCO3 for effectively removal of Hg0 from flue gas. The hierarchical structure of the sorbent was generated by CaCO3 and shaped by using staged pyrolysis temperatures. Large numbers of oxygen-containing functional groups were generated with the hierarchical pore formation. Because of their hierarchical porous structures and large numbers of ligands, the efficiency of Hg0 removal by the hierarchical sorbent was higher than that of conventional biochar by 40% to 65% at temperature range from 80 to 180 °C. Mechanistic studies showed that Hg0 was adsorbed on the surfaces of the hierarchical pores with different binding energies, and the ratio of mesopores could be a more critical factor in the Hg0 adsorption capacity of adsorbents with hierarchical porous structures. Meanwhile, the Hg0 removal with the hierarchical sorbent showed better resistance toward flue gas components (SO2 and H2O) than that with traditional biochar probably because of better transfer of the complex components in the sorbent. The high-performance and cost-effective carbon adsorbent described in this paper has great promise for Hg0 removal from flue gas.

中文翻译：

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用 CaCO3 模板合成的分层多孔生物炭可有效吸附烟气中的 Hg0

摘要 在纳米级CaCO3 存在下，稻草热解制备了一种分级多孔碳吸附剂，可有效去除烟气中的Hg0。吸附剂的分级结构由 CaCO3 生成，并通过使用分级热解温度进行成形。随着分级孔的形成，产生了大量的含氧官能团。由于其分级多孔结构和大量配体，分级吸附剂在 80 至 180 °C 的温度范围内去除 Hg0 的效率比传统生物炭高 40% 至 65%。机理研究表明，Hg0 吸附在具有不同结合能的分级孔表面，介孔比例可能是影响具有分级多孔结构的吸附剂对 Hg0 吸附能力的更关键因素。同时，与传统生物炭相比，分级吸附剂去除 Hg0 对烟气成分（SO2 和 H2O）具有更好的抵抗力，这可能是因为吸附剂中复杂成分的转移更好。本文中描述的高性能且具有成本效益的碳吸附剂在去除烟气中的 Hg0 方面具有广阔的前景。