Nano-cerium vanadate: A novel inorganic ion exchanger for removal of americium and uranium from simulated aqueous nuclear waste

• Published in: Journal of hazardous materials 2014-09, Vol.280, p.63-70
• Main Authors: Banerjee, Chayan, Dudwadkar, Nilesh, Tripathi, Subhash Chandra, Gandhi, Pritam Maniklal, Grover, Vinita, Kaushik, Chetan Prakash, Tyagi, Avesh Kumar
• Format: Article
• Language: English
• Subjects: Adsorption; Americium; Americium - isolation & purification; Applied sciences; Atmospheric pollution; Cerium - chemistry; Cerium vanadate; Chemical engineering; Co-precipitation; Exact sciences and technology; Ion exchange; Kielland plot; Kinetics; Microscopy, Electron, Transmission; Nanoparticles - chemistry; Pollution; Radioactive wastes; Sorption isotherm; Uranium; Uranium - isolation & purification; Vanadates - chemistry; Wastes; Water Pollutants, Radioactive - isolation & purification; X-Ray Diffraction
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2014.07.026

•Template free, low temperature synthesis of CeVO4 nanopowders.•Thermodynamically and kinetically favourable uptake of Am(III) and U(VI) exhibited.•Kd and ΔG° values for Am(III) and U(VI) uptake in pH 1–6 are reported.•Interdiffusion coefficients and zeta potential values in pH 1–6 are reported.•Possible application in low level aqueous nuclear waste remediation. Cerium vanadate nanopowders were synthesized by a facile low temperature co-precipitation method. The product was characterized by X-ray diffraction and transmission electron microscopy and found to consist of ∼25nm spherical nanoparticles. The efficiency of these nanopowders for uptake of alpha-emitting radionuclides 233U (4.82MeV α) and 241Am (5.49MeV α, 60keV γ) has been investigated. Thermodynamically and kinetically favorable uptake of these radionuclides resulted in their complete removal within 3h from aqueous acidic feed solutions. The uptake capacity was observed to increase with increase in pH as the zeta potential value decreased with the increase in pH but effect of ionic strength was insignificant. Little influence of the ions like Sr2+, Ru3+, Fe3+, etc., in the uptake process indicated CeVO4 nanopowders to be amenable for practical applications. The isotherms indicated predominant uptake of the radioactive metal ions in the solid phase of the exchanger at lower feed concentrations and linear Kielland plots with positive slopes indicated favorable exchange of the metal ions with the nanopowder. Performance comparison with the other sorbents reported indicated excellent potential of nano-cerium vanadate for removing americium and uranium from large volumes of aqueous acidic solutions.