Abstract:For the preparation of an ideal material for the emergency disposal of Pb(Ⅱ) contaminated water, polyacrylonitrile was selected as the matrix to be chemically modified with diethylenetriamine (DETA), and a kind of polyamine chelating nanofiber (D-PAN) has been successfully prepared. The physical and chemical structure analysis by SEM, BET, FTIR and XPS was performed. Amine groups was successfully introduced into three-dimensional network of intertwined fiber filaments which enhanced the adsorption capacity. It had the best adsorption performance at pH 5.0. The adsorption equilibrium could be reached within 2 h with an adsorption rate constant 0.06 min-1. The maximum adsorption capacity was 1.73 mmol/g obtained by fitting with Langmuir model. Moreover, D-PAN had a significant "salt-promoting" effect, and the adsorption amount of Pb (II) in the salt-containing system could be nearly doubled. Combining the results of XPS and DFT, it was found that Pb(Ⅱ) could be removed by chelating with N atoms in polyamine groups to form bidentate and tridentate complexes. Furthermore, D-PAN exhibited excellent structural stability after multiple regeneration. In summary, D-PAN has the advantages of fast adsorption, large capacity and easy regeneration, and has broad application prospects in the field of Pb (Ⅱ) polluted water remediation.