Facile functionalized of SBA-15 via a biomimetic coating and its application in efficient removal of uranium ions from aqueous solution.

Synthesis of Fe3O4@TiO2 core–shell magnetic composites for highly efficient sorption of uranium (VI)

Equilibrium, kinetic and thermodynamic studies on the removal of U(VI) by low cost agricultural waste.

Cyclodextrin-modified graphene oxide nanosheets (denoted as CD/GO) were synthesized by an in - situ polymerization method and characterized by as well as Fourier transform-infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and potentiometric acid-base titration. The characterization results indicated that CD was successfully grafted onto GO surfaces by forming a chemical bond. Mutual effects on the simultaneous removal of hexavalent uranium and humic acid by CD/GO from aqueous solution were investigated. The results indicated that U(VI) and humic acid (HA) sorption on CD/GO were greatly affected by pH and ionic strength. The presence of HA enhanced U(VI) sorption at low pH and reduced U(VI) sorption at high pH, whereas the presence of U(VI) enhanced HA sorption. The surface adsorbed HA acted as a “bridge” between U(VI) and CD/GO, and formed strong inner-sphere surface complexes with U(VI). Sorption isotherms of U(VI) or HA on CD/GO could be well fitted by the Langmuir model. This work highlights that CD/GO can be used as a promising material in the enrichment of U(VI) and HA from wastewater in U(VI) and humic substances obtained by environmental pollution cleanup.

Simultaneous removal of uranium and humic acid by cyclodextrin modified graphene oxide nanosheets

Separation scientists and radiochemists aim to recover valuable long-lived radionuclides from high-level nuclear waste solution before its safe geological disposal. In last few years, researchers have exploited biosorption for nuclear waste management as an alternative to conventional liquid–liquid separation techniques. This review outlines various methods employed for the preparation of biosorbents. Importantly, nuclear waste treatment using biosorbents has been discussed in detail along with adsorption mechanisms. The main objective of this review is to provide vital information on the developments that have been made so far in the domain of biosorption, exclusively for nuclear waste management

Biosorption-an alternative method for nuclear waste management: A critical review

Experiments on the removal and recovery of U(VI) from aqueous solution by tea waste were conducted. The adsorbent was characterized by scanning electron microscope and energy dispersive spectrometer before and after the adsorption treatment. The removal of U(VI) amounts to 86.80 % at optimum pH 6. The adsorption process reaches its equilibrium in 12 h at 308 K, and the kinetic characteristic can be described by the pseudo-second-order kinetic equation. The amount of adsorption increases from 22.92 to 142.21 mg g−1 with the decrease of tea waste dosage from 100 to 10 mg for solution with an initial uranium concentration of 50 mg L−1. Desorption for the four strippants is higher than 80 %. The equilibrium data are more agreeable with Freundlich isotherm than Langmuir isotherm.

Xi-Tao Liu

Papers

Removal and recovery of uranium from aqueous solution by tea waste