Preparation and Characterization of a Novel Hybrid Chelating Material for Effective Adsorption of Cu(II) and Pb(II)

The discharge of heavy metal ions such as Cu and Pb poses a severe threat to public health and the environment owing to their extreme toxicity and bioaccumulation through food chains. Herein, we report a novel organic-inorganic hybrid adsorbent, Al(OH)-poly(acrylamide-dimethyldiallylammonium chloride)-graft-dithiocarbamate (APD), for rapid and effective removal of Cu and Pb. In this adsorbent, the "star-like" structure of Al(OH)-poly(acrylamide-dimethyldiallylammonium chloride) served as the support of dithiocarbamate (DTC) functional groups for easy access of heavy metal ions and assisted development of large and compact floccules. The synthesized adsorbent was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). APD was demonstrated to have rapid adsorption kinetics with an initial rate of 267.379 and 2569.373mg/(g·min) as well as superior adsorption capacities of 317.777 and 586.699mg/g for Cu and Pb respectively. The adsorption process was spontaneous and endothermic, involving intraparticle diffusion and chemical interaction between heavy metal ions and the functional groups of APD. To assess its versatility and wide applicability, APD was also used in turbid heavy metal wastewater, and performed well in removing suspended particles and heavy metal ions simultaneously through flocculation and chelation. The rapid, convenient and effective adsorption of Cu and Pb gives APD great potential for heavy metal decontamination in industrial applications.