Title
Chemically modified glucuronoxylan: a novel material for heavy metal ion removal from aqueous and spiked high hardness groundwater
Authors
GULZAR MUHAMMAD AZHAR ABBAS MUHAMMAD AJAZ HUSSAIN MUHAMMAD SHER and NAZIA SHAHANA ABBAS

Received September 6, 2017
Published Volume 52 Issue 9-10 October-December
Keywords cadmium removal, polysaccharides, Mimosa pudica hydrogel, succinylation, regeneration

Abstract
Glucuroxylan (GX) was isolated from Mimosa pudica seeds. Then, a novel material – sodium salt of GX succinate (Na GXS) – was prepared and evaluated for Cd removal from distilled water (DW) and spiked high hardness groundwater (GW). The chemical structure and charge on the surface of Na-GXS (sorbent) was characterized by FTIR spectroscopy and zero point charge, respectively. Adsorption of Cd(II) onto Na-GXS was investigated with respect to pH, adsorption time, initial Cd(II) concentration and temperature. The pseudo-second-order kinetic model and Langmuir isothermal model were better fitted to the kinetics and adsorption isothermal data, respectively, for both DW and GW. The values of thermodynamic parameters, such as ∆S°, ∆G° and ∆H°, were determined for both DW and GW, indicating that the removal of Cd(II) was spontaneous, favorable and an exothermic process in nature. Na-GXS showed selective removal for Cd(II) from GW in the presence of naturally occurring Ca(II) and Mg(II) ions in GW. Regeneration studies were also carried out.