Tags

Type your tag names separated by a space and hit enter

Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)-grafted lignocellulosics.
J Environ Manage. 2009 Jan; 90(1):549-60.JE

Abstract

This study investigated the feasibility of using a new adsorbent prepared from coconut coir pith, CP (a coir industry-based lignocellulosic residue), for the removal of uranium [U(VI)] from aqueous solutions. The adsorbent (PGCP-COOH) having a carboxylate functional group at the chain end was synthesized by grafting poly(hydroxyethylmethacrylate) onto CP using potassium peroxydisulphate-sodium thiosulphite as a redox initiator and in the presence of N,N'-methylenebisacrylamide as a crosslinking agent. IR spectroscopy results confirm the graft copolymer formation and carboxylate functionalization. XRD studies confirm the decrease of crystallinity in PGCP-COOH compared to CP, and it favors the protrusion of the functional group into the aqueous medium. The thermal stability of the samples was studied using thermogravimetry (TG). Surface charge density of the samples as a function of pH was determined using potentiometric titration. The ability of PGCP-COOH to remove U(VI) from aqueous solutions was assessed using a batch adsorption technique. The maximum adsorption capacity was observed at the pH range 4.0-6.0. Maximum removal of 99.2% was observed for an initial concentration of 25mg/L at pH 6.0 and an adsorbent dose of 2g/L. Equilibrium was achieved in approximately 3h. The experimental kinetic data were analyzed using a first-order kinetic model. The temperature dependence indicates an endothermic process. U(VI) adsorption was found to decrease with an increase in ionic strength due to the formation of outer-sphere surface complexes on PGCP-COOH. Equilibrium data were best modeled by the Langmuir isotherm. The thermodynamic parameters such as DeltaG(0), DeltaH(0) and DeltaS(0) were derived to predict the nature of adsorption. Adsorption experiments were also conducted using a commercial cation exchanger, Ceralite IRC-50, with carboxylate functionality for comparison. Utility of the adsorbent was tested by removing U(VI) from simulated nuclear industry wastewater. Adsorbed U(VI) ions were desorbed effectively (about 96.2+/-3.3%) by 0.1M HCl. The adsorbent was suitable for repeated use (more than four cycles) without any noticeable loss of capacity.

Authors+Show Affiliations

Department of Chemistry, University of Kerala, Kariavattom, Trivandrum 695 581, India. tsani@rediffmail.comNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

18222595

Citation

Anirudhan, T S., et al. "Kinetic and Equilibrium Characterization of uranium(VI) Adsorption Onto Carboxylate-functionalized Poly(hydroxyethylmethacrylate)-grafted Lignocellulosics." Journal of Environmental Management, vol. 90, no. 1, 2009, pp. 549-60.
Anirudhan TS, Divya L, Suchithra PS. Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)-grafted lignocellulosics. J Environ Manage. 2009;90(1):549-60.
Anirudhan, T. S., Divya, L., & Suchithra, P. S. (2009). Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)-grafted lignocellulosics. Journal of Environmental Management, 90(1), 549-60. https://doi.org/10.1016/j.jenvman.2007.12.010
Anirudhan TS, Divya L, Suchithra PS. Kinetic and Equilibrium Characterization of uranium(VI) Adsorption Onto Carboxylate-functionalized Poly(hydroxyethylmethacrylate)-grafted Lignocellulosics. J Environ Manage. 2009;90(1):549-60. PubMed PMID: 18222595.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)-grafted lignocellulosics. AU - Anirudhan,T S, AU - Divya,L, AU - Suchithra,P S, Y1 - 2008/01/28/ PY - 2007/05/13/received PY - 2007/11/09/revised PY - 2007/12/08/accepted PY - 2008/1/29/pubmed PY - 2009/2/27/medline PY - 2008/1/29/entrez SP - 549 EP - 60 JF - Journal of environmental management JO - J Environ Manage VL - 90 IS - 1 N2 - This study investigated the feasibility of using a new adsorbent prepared from coconut coir pith, CP (a coir industry-based lignocellulosic residue), for the removal of uranium [U(VI)] from aqueous solutions. The adsorbent (PGCP-COOH) having a carboxylate functional group at the chain end was synthesized by grafting poly(hydroxyethylmethacrylate) onto CP using potassium peroxydisulphate-sodium thiosulphite as a redox initiator and in the presence of N,N'-methylenebisacrylamide as a crosslinking agent. IR spectroscopy results confirm the graft copolymer formation and carboxylate functionalization. XRD studies confirm the decrease of crystallinity in PGCP-COOH compared to CP, and it favors the protrusion of the functional group into the aqueous medium. The thermal stability of the samples was studied using thermogravimetry (TG). Surface charge density of the samples as a function of pH was determined using potentiometric titration. The ability of PGCP-COOH to remove U(VI) from aqueous solutions was assessed using a batch adsorption technique. The maximum adsorption capacity was observed at the pH range 4.0-6.0. Maximum removal of 99.2% was observed for an initial concentration of 25mg/L at pH 6.0 and an adsorbent dose of 2g/L. Equilibrium was achieved in approximately 3h. The experimental kinetic data were analyzed using a first-order kinetic model. The temperature dependence indicates an endothermic process. U(VI) adsorption was found to decrease with an increase in ionic strength due to the formation of outer-sphere surface complexes on PGCP-COOH. Equilibrium data were best modeled by the Langmuir isotherm. The thermodynamic parameters such as DeltaG(0), DeltaH(0) and DeltaS(0) were derived to predict the nature of adsorption. Adsorption experiments were also conducted using a commercial cation exchanger, Ceralite IRC-50, with carboxylate functionality for comparison. Utility of the adsorbent was tested by removing U(VI) from simulated nuclear industry wastewater. Adsorbed U(VI) ions were desorbed effectively (about 96.2+/-3.3%) by 0.1M HCl. The adsorbent was suitable for repeated use (more than four cycles) without any noticeable loss of capacity. SN - 0301-4797 UR - https://www.unboundmedicine.com/medline/citation/18222595/Kinetic_and_equilibrium_characterization_of_uranium_VI__adsorption_onto_carboxylate_functionalized_poly_hydroxyethylmethacrylate__grafted_lignocellulosics_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0301-4797(07)00423-9 DB - PRIME DP - Unbound Medicine ER -