title: An investigation into the adsorption of thorium(IV) from aqueous solutions by a carboxylate-functionalised graft copolymer derived from titanium dioxide-densified cellulose.
abstract: The use of a carboxylate-functionalized graft copolymer (PGTDC-COOH) based on titanium dioxide-densified cellulose (TDC) for the removal and recovery of thorium(IV) [Th(IV)] from industrial wastewater is reported in this paper. Infrared spectroscopy and X-ray diffractometer were used to characterize the adsorbent material. Batch equilibrium experiments showed that the adsorbent exhibited 98.6 ± 3.1% adsorption from an initial concentration of 10 mg/L Th(IV) solution at pH 5.0. The sorption kinetics have been analysed by pseudo-first-order and pseudo-second-order kinetic models and the adsorption kinetics was described by pseudo-second-order model. The experimental data obeyed Langmuir isotherm and the maximum monolayer adsorption capacity for Th(IV) was also found to be 92.23 ± 2.4 mg/g at 30 °C. The desorption capacity of HCl concentrations of different strengths ranging from 0.001 to 0.1 M was also studied. Maximum desorption of 98.2 ± 2.8% for Th(IV) occurred with 0.1 M HCl. The adsorption efficiency towards Th(IV) ion removal was tested using artificial sea water. Almost complete removal was possible with 3.5 g of the adsorbent from 1 L of the sea water.
authors.affiliation: Department of Chemistry, University of Kerala, Kariavattom, Trivandrum 695 581, Kerala, India. tsani@rediffmail.com
authors.forename: T S
authors.initials: TS
authors.lastname: Anirudhan
authors.forename: S S
authors.initials: SS
authors.lastname: Sreekumari
authors.forename: S
authors.initials: S
authors.lastname: Jalajamony
mesh_terms: D000327:Adsorption; D002264:Carboxylic Acids / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D011109:Polymethacrylic Acids / Q000737:chemistry; D011850:Radioactive Waste; D012623:Seawater / Q000737:chemistry; D012996:Solutions; D013910:Thorium / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D014875:Water Pollutants, Radioactive / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D011109:Polymethacrylic Acids; D011850:Radioactive Waste; D012996:Solutions; D014875:Water Pollutants, Radioactive; C009495:titanium dioxide; C030613:polymethacrylic acid; D013910:Thorium; D002482:Cellulose; D014025:Titanium