Characterization and adsorption properties of the chelating hydrogels derived from natural materials for possible use in the improvement of groundwater quality

Abstract

ABSTRACT:A new carrageenan based chelating copolymer sorbent was prepared by gamma radiation induced copolymerization and crosslinking of kappa-carrageenan (kCar) and acrylic acid (AAc). The swelling characteristics of the prepared copolymer were investigated by studying the effect of time, pH, and ionic strength of the swelling medium. The sorption capacities of the chelating copolymer for Fe, Pb, Mn, Zn, Cu, Sr, Cd, and Al were 172, 202, 202, 216, 221, 230, 239, and 244 mg/g respectively. The Freundlich and Langmuir adsorption isotherms were used to validate the metal uptake data and heats of adsorption for the investigated metal ions were calculated. The re-use experiment showed that the prepared hydrogel could be regenerated upto at least 10 times. Because of the promising data collected from bench scale experiments, the prepared copolymer was examined as chelating sorbent to improve the quality of some groundwater resources.

Adsorption and desorption of Sr(II) ions in the gels based on polysaccharide derivates

“…The result reveals that, at the beginning, the adsorption mainly occurs on the surface of the adsorbents, so the adsorption rate was fast [26]. After the surface adsorption is saturated, the adsorption gradually proceeds into the inner part of the porous adsorbents via the diffusion of metal ions into the polymer matrix, leading to a lower adsorption rate [27].…”

“…2 h for HPMCP gels. According to Langmuir, the reversible sorption-desorption process can be described by the following equation [27]:…”

Carboxymethylated-bacterial cellulose for copper and lead ion removal

“…Among these treatments, adsorption has attracted a considerable interest. Adsorption method is considered to be effective and economic due to the fact that many abundant, low-cost, renewable and easily modified materials such as cellulose and chitosan can be used in adsorption [4][5][6][7][8][9][10][11]. For example, application of cellulose modified by a complexing group involving an amine function (amidoxyl [12,13], aminoalkyl [14]), an anionic moiety (phosphate [15], thiolate [16], carboxymethyl [17]) or graft copolymers [18] has been reported.…”

Improvement of water quality using alginate/montmorillonite composite beads

“…Therefore, there have been attempts to utilize low cost, naturally occurring adsorbents, to remove contaminants from wastewater 7, 8. These kinds of adsorbents, which are biological‐based materials such as Cephalosporium aphidicola ,5 Pinus sylvestris ,9 Saccharomyces cerevisiae ,10 Sargassum natans ,11 Botrytis cinerea ,12 Neurospora crassa ,13 Aspergillus niger ,14 R. arrhizus ,15 Bacillus sp.,16 alginate,17 chitosan,18 and carrageenan19; natural clay minerals such as kaolinite,20–23 illite,24 bentonite,25, 26 montmorillonite,20, 23, 27 zeolite,28, 29 and sepiolite30, 31 have been used to remove heavy metal ions from aqueous solutions by adsorption.…”