磁性石墨烯基复合吸附剂对脱硫浆液中Hg2+还原控制的研究

项目名称： 磁性石墨烯基复合吸附剂对脱硫浆液中Hg2+还原控制的研究

项目编号： No.51506066

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 能源与动力工程

项目作者： 田冲

作者单位： 华中科技大学

项目金额： 20万元

中文摘要： 本项目针对燃煤电厂WFGD脱硫石膏浆液中Hg2+还原再释放造成环境二次污染，及螯合剂固Hg后在脱硫石膏中富集的问题，交叉融汇燃烧学、环境科学、及功能材料学等学科基础理论，开发可再生磁性石墨烯基复合吸附剂对Hg2+进行吸附，并利用磁分离特性与脱硫石膏分离，抑制Hg再释放，防止Hg在脱硫石膏中富集。通过实验研究结合理论分析，确立脱硫浆液中Hg2+还原机制，建立Hg2+还原模型；考察磁性石墨烯基吸附剂对脱硫石膏浆液中Hg2+吸附性能，阐述其对Hg2+吸附机理，建立其对Hg2+吸附动力学模型；进而利用Ag-Hg反应机理，在磁性石墨烯基吸附剂表面修饰纳米Ag颗粒，开发磁性石墨烯基复合吸附剂实现脱硫石膏浆液中Hg2+/Hg0联合吸附，并确立复合吸附剂分离再生化学工艺流程，评估其放量生产及工业应用前景，为WFGD系统同步脱Hg安全运行提供技术支撑，为拓展石墨烯基功能材料在能源环保领域利用奠定理论基础。

中文关键词： 湿法脱硫；汞二次释放；石墨烯功能纳米材料；汞吸附；磁分离

英文摘要： The proposal is focusing on the issues of Hg2+ reduction and re-emission of Hg0 in the gypsum slurry, which would result in serious secondary pollutions. Although Hg2+ would be stabilized by addition of additives and/or chelants thus inhibiting its reduction, Hg would be enriched in the gypsum, which cause serious potential risk for gypsum utilization. Herein, we propose to develop an regenerate adsorbent based on graphene for Hg2+ absorption in gypsum slurry. For one thing, the adsorbents would have high selective performance and adsorption efficiency for Hg2+. And another, the adsorbents would be easily segregated via magnetic separation from the gypsum slurry. Finally the adsorbents could be regenerated by chemical methods treatment. We aim to fundamentally control Hg2+ re-emission and avoid enrichment of Hg in gypsum. The project is supported by multidisciplinary of combustion theory, environmental science, functional material science. It is supposed to find the pathways of Hg2+ reduction in gypsum to slurry by simulating the flue gas desulfurization system. We would also reveal the adsorption mechanisms of Hg2+ on functionalized grapheme oxides and to establish the kinetic modal for Hg2+ adsorption. Moreover, by decorating Ag nanoparticles on the sheet of magnetic graphene oxide to achieve the goal for the combination adsorption of Hg2+ and Hg0. For adsorbents regeneration process, we would like to reveal the optimal chemical process for adsorbent regeneration and evaluate the possibility of the volume production of adsorbents. The work would provide a theoretical basis and technical support for simutaneous Hg removal by WFGD, and also expand the utilization of fuctionalzed graphene material in the field of energy and environment protection.

英文关键词： WFGD;Hg re-emission ;functionalized graphene nanocomposites;Hg adsorption ;magnetic separation