Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China.
Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi, 214122, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou, 215011, China.
J Environ Manage. 2023 Jan 1;325(Pt B):116427. doi: 10.1016/j.jenvman.2022.116427. Epub 2022 Oct 21.
A novel biochar involving pyrolysis of dewatered algal waste combined with KOH and residual FeCl co-activation was synthesized as an efficient sorbent specifically for Hg removal from coal-fired flue gas. It was found that the S of biochar co-activated by KOH and FeCl (BCFK) was 195.82 m g, much higher than that of single FeCl activated biochar (BCF) of 133.38 m g and un-activated biochar (UBC) of 20.36 m g. Furthermore, BCFK exhibited higher magnetization characteristics as well as elemental Fe and Cl contents of 2.71% and 10.33%, respectively, based on the combined characterization of XPS and VSM, etc., which is a jump of about 10-fold compared to BCF. This allows BCFK to show the best Hg removal capability of 689.66 μg g under the inlet Hg concentration of 100 μg m and 150 °C, according to pseudo-second-order kinetic model. Further analysis by XPS and Hg-TPD (Temperature Programmed Desorption) revealed that oxidation by Cl∗ radicals and C-Cl as well as weak chemisorption contributed to the removal of Hg. Eventually, this efficient, simply prepared, low-cost and easily separable biochar distinguished itself in comparison to other materials. This will undoubtedly promote the valorization of algae and provide a reliable alternative material for the treatment of coal-fired flue gas.
一种新型生物炭，涉及脱水藻类废物与 KOH 和残留 FeCl 共活化的热解，被合成作为一种从燃煤烟气中去除汞的有效吸附剂。研究发现，KOH 和 FeCl 共活化生物炭（BCFK）的 S 比单 FeCl 活化生物炭（BCF）的 133.38 m/g 和未活化生物炭（UBC）的 20.36 m/g 高得多。此外，基于 XPS 和 VSM 等综合表征，BCFK 表现出更高的磁化特性以及 2.71%和 10.33%的元素 Fe 和 Cl 含量，与 BCF 相比约增加了 10 倍。这使得 BCFK 在入口 Hg 浓度为 100 μg/m 和 150°C 下，表现出最佳的 689.66μg/g 的 Hg 去除能力，符合准二级动力学模型。进一步的 XPS 和 Hg-TPD（温度程序脱附）分析表明，Cl*自由基和 C-Cl 的氧化以及弱化学吸附有助于 Hg 的去除。最终，这种高效、简单制备、低成本和易于分离的生物炭与其他材料相比具有明显的优势。这无疑将促进藻类的增值，并为燃煤烟气的处理提供可靠的替代材料。
