Indian Journal of Chemical Technology, Vol.16, No.5, 417-425, 2009
Removal of Pb(II) from aqueous solutions by using dioctyl sodium sulphosuccinate-EDTA modified Amberlite XAD-7HP resin
The removal of Pb(II) from aqueous solutions by using modified Amberlite XAD-7HP resin has been studied. The resins have been prepared by complete mixing of Amberlite XAD-7HP resin with anionic surfactant-dioctyl sodium sulphosuccinate (DOSSS) and EDTA-disodium salt.(Chelating agent) in an aqueous solution. SEM studies revealed the morphological observations of the unloaded adsorbent and thereby changes in the adsorbed polymeric resins. FTIR studies showed that the impregnation of the extractant on the Amberlite XAD-7HP resin is achieved partly through hydrophobic interaction between the alkyl group of the extractant and aliphatic chain (methyl) of the support and also through polar or electrostatic forces. The equilibrium adsorption level was determined as a function of contact time, pH and adsorbent doses. Adsorption isotherms of Pb(II) on adsorbent were determined and correlated with common isotherm equations such as Langmuir and Freundlich models. ne adsorption kinetics of Pb(II) on modified XAD-7HP resin could be best described by the pseudo-second-order model. The lead(II) ions could be successfully recovered from the modified XAD-7HP resin by treatment with 7% NaCl. The modified XAD-7HP resins thus regenerated could be used again to remove the heavy metal ions. The adsorbent was also tested for the removal of Pb(II) from lead battery wastewater.
Keywords:Lead(II) removal;Dioctyl sodium sulphosuccinate;EDTA;Amberlite XAD-7HP resin;Adsorption isotherms;Kinetics