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Four kinds of silica gel supported chelating adsorbents with different multidentate ligands were synthesized by the cross-link reaction.The obtained adsorbents were named as SG-AM,SG-ASM,SG-AD and SG-ASD.FT-IR analysis and thermogravimetry analysis were used to characterize the prepared adsorbents.Their adsorption properties of Pb(Ⅱ),Hg(Ⅱ),Cu(Ⅱ),Zn(Ⅱ)and Cd(Ⅱ)were also investigated.The results showed that SG-AD and SG-ASD showed a higher performance towards Pb(Ⅱ)and Hg(Ⅱ),especially towards Hg(Ⅱ).Adsorption kinetics suggested that the adsorption processes of Pb(Ⅱ)and Hg(Ⅱ)on SG-AD and SG-ASD were governed by film diffusion and followed a pseudo-second-order model.The Langmuir model and Scatchard model were applied to fit the experimental equilibrium data for SG-AD and SG-ASD.With increasing temperature,the adsorption capacities and affinity constants of SG-AD and SG-ASD for Pb(Ⅱ)and Hg(Ⅱ)were increased.SG-ASD which contained two kinds of multidentate ligands showed strong chelating affinity to Hg(Ⅱ).Langmuir model and Scatchard model can be integrated in describing the processes of heavy metal adsorption.