Sun Jiaxing, Chen Heng, Qi Dongxu, Wu Hao, Zhou Changsong, Yang Hongmin
School of Energy and Mechanical Engineering, Nanjing Normal University, Nanjing, People's Republic of China.
Jiangsu Provincial Key Laboratory of Materials Cycling & Pollution Control, School of Energy and Mechanical Engineering, Nanjing Normal University, Nanjing, People's Republic of China.
Environ Technol. 2020 Apr;41(11):1366-1379. doi: 10.1080/09593330.2018.1534893. Epub 2018 Oct 16.
Graphene oxide (GO) is a new promising nanometer material in a superconductor and wastewater heavy metal ions removal for its functionalized groups. Ethylenediaminetetraacetic acid functionalized graphene oxide complexes (EDTA-GO) was produced by a realizable silanization chemical reaction. Characteristics of Hg(II) removal in desulphurization wastewater was also under investigation. The chemical composition and microstructures of the EDTA-GO adsorbents were characterized by X-ray photoelectron spectroscopy (XPS), Transmission electron microscope (TEM), Scanning Electron Microscopy (SEM) analyses. To investigate the performance of EDTA-GO adsorbents on adsorption of Hg(II) in wastewater of wet flue gas desulphurization (WFGD), experiments were performed to optimize the main influence factors such as reaction temperatures (35-70°C), pH values(2-13), contact time (0-120 min), initial Hg(II) concentrations(800 ug/L) and adsorbent doses (20-50 mg/L). The maximum uptake removal efficiency (97.14%) was achieved under the optimal conditions at the pH of 7, the temperature of 70°C, the Hg(II) concentration of 1200 μg/L and the EDTA-GO dose of 40 mg/L. The kinetic data fitting results were well consistent with the pseudo-second-order model (= 0.99997) and a spontaneous and endothermic adsorption reaction was elaborated by thermodynamics studies (Δ < 0, Δ > 0, ΔS > 0). The experiments of recycled adsorbents by HCl generation were carried out to obtain the performance of the reused EDTA-GO adsorbent, the fourth regenerative adsorption efficiency still maintained 80.4%, which indicated that excellent potential application in desulphurization wastewater treatment.
氧化石墨烯（GO）因其官能团而成为超导体和废水中重金属离子去除领域一种很有前景的新型纳米材料。通过可实现的硅烷化化学反应制备了乙二胺四乙酸功能化氧化石墨烯复合物（EDTA-GO）。同时也在研究脱硫废水中汞（II）的去除特性。采用X射线光电子能谱（XPS）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）分析对EDTA-GO吸附剂的化学成分和微观结构进行了表征。为研究EDTA-GO吸附剂对湿法烟气脱硫（WFGD）废水汞（II）的吸附性能，进行了实验以优化主要影响因素，如反应温度（35 - 70°C）、pH值（2 - 13）、接触时间（0 - 120分钟）、初始汞（II）浓度（800μg/L）和吸附剂剂量（20 - 50mg/L）。在pH为7、温度为70°C、汞（II）浓度为1200μg/L和EDTA-GO剂量为40mg/L的最佳条件下，实现了最大吸附去除效率（97.14%）。动力学数据拟合结果与准二级模型吻合良好（= 0.99997），热力学研究表明这是一个自发的吸热吸附反应（Δ < 0，Δ > 0，ΔS > 0）。进行了用盐酸再生吸附剂的实验以获得重复使用的EDTA-GO吸附剂的性能，第四次再生吸附效率仍保持在80.4%，这表明其在脱硫废水处理中具有优异的潜在应用价值。
