摘要
In order to investigate the solidification effect ofPb2+ by slag-steel slag system, X-ray powder diffraction (XRD) and X-ray absorption fine structure (XAFS) are introduced to study the microstructure and mechanism for slag-steel slag material solidified Pb2+.The Pb ion leaching experiment data indicate that the slag-steel slag material produces perfect solidification effect when the Pb ion concentration ranges from 1% to 5%.The Pb leaching concentration is 0.72mg/L on the 28th day when the.original Pb ion concentration is 5%, much higher than 4.7 mg/L of the cement sample.The Pb leaching concentration of all solidified samples on the 28th day is lower than 5mg/L prescribed in the Identification Standard for Hazardous Wastes.XRD spectra show that in samples mixed with Pb, there is a peak derivation of C-S-H and ettringite, and some diffraction peaks that contain Pb-doped double salt present themselves up.X-ray absorption fine structure (XAFS) is used to study the microstructure and mechanism for solidified Pb2+ by the slag-steel slag material.The results show that the slag-steel slag material can better inspire the exchange of Pb ion and Ca ion, enabling Pb ion to be captured and enter the silicon-oxygen tetrahedron network to balance the electric charge, or to substitute Ca ion captured in the lattice so as to prevent the leaching of Pb ion by forming double salt precipitation.