Fan Jinyuan, Yan Jiahao, Zhou Mengya, Xu Yuan, Lu Yuwei, Duan Ping, Zhu Yingcan, Zhang Zuhua, Li Wengui, Wang Aiguo, Sun Daosheng
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China; Key Laboratory of Advanced Building Materials of Anhui Province, Anhui Jianzhu University, Hefei 230022, China; Guangxi Key Laboratory of New Energy and Building Energy Saving, Guilin University of Technology, Guilin 541004, China.
J Hazard Mater. 2023 Jul 5;453:131380. doi: 10.1016/j.jhazmat.2023.131380. Epub 2023 Apr 5.
To solve heavy metals leaching problem in the utilization of various industrial solid wastes, this work investigated the heavy metals immobilization of ternary geopolymer prepared by nickel slag (NS), lithium slag (LS), and metakaolin (MK). Compressive strength was measured to determine the optimum and appropriate mix proportions. The leaching characteristics of typical heavy metals (Cu (Ⅱ), Pb (Ⅱ), and Cr (Ⅲ)) in acid, alkali, and salt environments were revealed by Inductively Coupled Plasma (ICP). The heavy metals immobilization mechanism was explored by Mercury Intrusion Porosimetry (MIP), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) tests. The experimental results show that the group with a mass ratio of NS, LS and MK of 1:1:8 exhibits the highest compressive strength, which reaches 69.1 MPa at 28 d. The ternary geopolymer possesses a desirable capacity for immobilizing inherent heavy metals, where the immobilization rates of Cu and Pb reach 96.69 %, and that of Cr reaches 99.97 %. The leaching concentrations of Cr and Pb increase when the samples are exposed to acidic and alkaline environments. Cu and Pb are mainly physically encapsulated in geopolymer. Additionally, immobilization of Cr mainly involves physical encapsulation and chemical bonding.
为解决各类工业固体废物利用过程中的重金属浸出问题，本研究考察了由镍渣（NS）、锂渣（LS）和偏高岭土（MK）制备的三元地质聚合物对重金属的固化效果。通过测量抗压强度来确定最佳和合适的配合比。采用电感耦合等离子体（ICP）揭示了典型重金属（Cu（Ⅱ）、Pb（Ⅱ）和Cr（Ⅲ））在酸、碱和盐环境中的浸出特性。通过压汞法（MIP）、X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）测试探究了重金属的固化机理。实验结果表明，NS、LS和MK质量比为1:1:8的组表现出最高的抗压强度，在28天时达到69.1MPa。三元地质聚合物对固有的重金属具有良好的固化能力，其中Cu和Pb的固化率达到96.69%，Cr达到了99.97%。当样品暴露于酸性和碱性环境中时，Cr和Pb的浸出浓度增加。Cu和Pb主要通过物理方式包裹在地质聚合物中。此外，Cr的固化主要涉及物理包裹和化学键合。
