Synthesis and implication of grafted polymeric adsorbent for heavy metal removal

摘要

Nowadays, grafted polymeric composite has received much attention as an alternative adsorbent of heavy metal removal. The grafted polymeric adsorbent (GPA) in the form of composite was prepared using diallyl dimethyl ammonium chloride (DADMAC) and acrylic acid embedded nonwoven irradiated polythene sheet. The prepared GPA was characterized using Fourier transform infra-red (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis to understand molecular interaction, surface morphology and physical phenomena of them. The effect of parameters including pH, initial metal concentration, contact time, as well as temperature on the adsorption of Cu(Ⅱ)/Cr(Ⅵ) was studied sequentially. The result shows that the GPA had utmost grafting yield of 192% with reaction time 4.0 h at 50 kGy. The maximum adsorption was found up to 153.89 mg Cu/g and 17.34 mg Cr/g with an initial concentration of 1000 ppm, a contact time of 24 h, pH of 4.84 [Cu(Ⅱ)], and 1.5 [Cr(Ⅵ)] at room temperature (25 ℃) indicating superb synergetic adsorption capacity of the GPA. Comparing the Langmuir and Freundlich adsorption isotherm models, the former fitted well with Cr and latter with Cu adsorption data implying that the models can be applied to uptake Cu(Ⅱ)/Cr(Ⅵ) by GPA. In the kinetic adsorption experiment, adsorbed metal almost reached equilibrium about 10 h for the GPA and followed the pseudo-second-order kinetic model. Thus, the GPAs are propriety and competent in terms of capability and reusability to remove heavy metal ions.