Sorption Of Europium Research Articles

Sorption and possible preconcentration of europium and gadolinium ions from aqueous solutions by Mn3O4 nanoparticles

Mn3O4 nanoparticles were prepared by co-precipitation method. The prepared samples had been characterized to find the compositional, structural, and functional properties, by means of EDX, XRD, and FTIR, respectively. The prepared manganese oxide nanoparticles (Mn3O4 NPs) have average crystallite size of 30–35 nm. The effect of different parameters on the uptake of Eu(III) and Gd(III) by Mn3O4 nanoparticles such as pH, initial metal concentration, shaking time, and temperature was examined. The shaking time for both adsorption and desorption was found to be 5 h. The sorption capacities at equilibrium with regards to Eu(III) and Gd(III) were 26.8 and 12.6 mg/g, respectively. Kinetically, the sorption of both elements fitted well to pseudo-second-order model. Sorption equilibrium isotherm obeys more favorably the Langmuir isotherm model. Desorption process of Eu(III) and Gd(III) from Mn3O4 NPs was highly managed using 2.0 M HNO3. A preconcentration factor of 70 and 20 was obtained for Gd and Eu, respectively, using 0.1 g of the Mn3O4 nanoparticles.

Exfoliation and europium(III)-functionalization of α-titanium phosphate via propylamine intercalation: from multilayer assemblies to single nanosheets

Layered α-titanium phosphate intercalated with propylamine, Ti(HPO4)2·2C3H7NH2·H2O (α-TiPPr), has been synthesized by solid-vapour reaction and then exfoliated via a single-stage approach based on overnight stirring in aqueous medium. The obtained nanosheets were then functionalized using solid–liquid reaction with europium(III) nitrate aqueous solutions. The obtained materials were characterized by powder X-ray diffraction (PXRD), N2 adsorption–desorption isotherms at 77 K, scanning electron microscopy (SEM), transmission electron microscopy (TEM, SAED, STEM-EDX), atomic force microscopy (AFM) and photoluminescence spectroscopy (PL). The europium(III) sorption takes place via two distinct pathways, the first is the previously reported C3H7NH3+/[Eu(H2O)6]3+ ion-exchange process into the titanium–phosphate interlayer space of the multilayered α-TiPPr. The second pathway is the self-assembly of single-sheets which is provoked by electrostatic interactions between the negatively charged titanium–phosphate sheets and the Eu(III)-aqueous cations, leading to the formation of layered nanoparticles.

Sorption of Eu (III) onto Nano-Sized H-Titanates of Different Structures

Hydrogen titanates (H-titanates) of different nanostructures (nanotubes, nanowires, nanosheets) have been synthesized by hydrothermal methods. The europium (III) sorption from aqueous solutions onto nano-sized H-titanates was studied as a function of contact time, pH values, and initial Eu (III) concentration in batch experiments. Reversibility of adsorption of europium has been investigated as well. Nano-sized H-titanates can be used for tri-valent f-elements removal in polluted water treatment due to fast and efficient sorption of Eu (III).

Kinetics of europium sorption to four different aluminum (hydr)oxides: Corundum, γ-alumina, bayerite, and gibbsite

Kinetic studies can improve our understanding of the environmental mobility of radionuclides by providing insight into sorption mechanisms occurring at the mineral-water interface. While nearly identical equilibrium europium sorption edges are obtained for gibbsite (γ-Al(OH)3), bayerite (α-Al(OH)3), corundum (α-Al2O3), and γ-Al2O3, differences in surface acidity and crystal structure result in distinct reaction rates. Batch kinetic experiments were performed to investigate europium sorption to four aluminum (hydr)oxide minerals as a function of time (10–120 min), mineral concentration (0.5–50 m2 L−1), pH (5–7), and europium concentration (10−8–10−6 M). Linear and non-linear pseudo-first and pseudo-second order rate equations were used to fit the data. The overall reaction rates and reaction orders with respect to proton concentration, mineral concentration, and europium concentration were determined, leading to a governing rate law for each mineral system. Europium sorption is characterized by a two-step reaction with a fast initial sorption step followed by a slower sorption or aging process. The pseudo-second order equations resulted in better model fits of the data. Using the non-linear pseudo-second order rate constants, it was observed that the reaction orders for each mineral system were similar but resulted in different overall reaction rates following the trend bayerite ∼ γ-Al2O3 > corundum > gibbsite. However, the calculated reaction orders are similar to those previously reported for plutonium(IV/V) interactions with iron (oxyhydr)oxide minerals, suggesting that these binary systems share similar elementary reactions.

Phosphonate and carboxylic acid co-functionalized MoS2 sheets for efficient sorption of uranium and europium: Multiple groups for broad-spectrum adsorption

It is significant to develop novel materials and techniques for efficient removal of radionuclides from radioactive wastes due to the radioactive and chemical toxicity. In this paper, we report a strategy for broad-spectrum adsorption of radionuclides by multiple groups-decorated adsorbents. Specifically, the adsorbents were prepared by grafting diethyl-(4-vinylbenzyl) phosphonate and maleic anhydride copolymers onto molybdenum disulfide sheets for the sorption of uranium(VI) and europium(III). The sorption efficiencies exhibited a dependency on pH, contact time and initial concentrations. The sorption reached the equilibrium within 60 min and followed a pseudo-second-order kinetic model. The maximum sorption capacities of the sorbents were 448.4 mg/g and 171.2 mg/g at pH 4.0 and 298.15 K for uranium(VI) and europium(III), respectively. The sorbent possessed a high efficiency of 98% in five sorption-desorption cycles without damage in chemical structures. XPS spectra showed that the sorption of uranium(VI) and europium(III) on the sorbents were originated from the interaction between multiple groups (such as sulfur, COOH, PO and PO) and uranium/europium. This work demonstrates that the adsorbent can be utilized as a promising material for the separation of broad-spectrum radionuclides from an aqueous solution.

Uranium and europium sorption on amidoxime-functionalized magnetic chitosan micro-particles

Magnetic chitosan particles were successfully modified by amidoxime-grafting (as evidenced by FTIR analysis, SEM-EDX analysis, elemental analysis, X-ray diffraction (XRD), thermogravimetric analysis and titration). The effect of pH was investigated showing optimum sorption at pH 4 for U(VI) and pH 5 for Eu(III). Uptake kinetics are relatively fast: the equilibrium was reached within 60–90 min; and the kinetic profiles were preferentially fitted by the pseudo-second order rate equation. Sorption isotherms are equally fitted by the Langmuir and the Sips equations; under optimal conditions maximum sorption capacity reaches 1.5 mmol U g−1 and 2.47 mmol Eu g−1. In bi-component solution, at pH close to 4.9, uranyl is enriched on the sorbent (higher selectivity coefficient) while maintaining high sorption capacities. The selectivity for Eu(III) sorption is higher at pH 2.3 but at the expense of a decrease in sorption capacities. Metal ions can be readily and fast desorbed using 0.5 M HCl solutions: 30–90 min are sufficient for achieving the complete desorption of U(VI) and about 95% of Eu(III) desorption. Sorption and desorption performances are maintained almost constant over 5 cycles of sorption/desorption: the sorbent can be efficiently recycled. Uranium was successfully recovered from alkaline leachate of a sedimentary dolostone ore material.

Synthesis and Sorption Performance of Novel Sorbents for Selective Solid-Phase Extraction of Eu(III) Ions from Aqueous Solutions

Magnesium-cadmium hydroxyapatite [(Mg-Cd)HAP] and novel multi-wall carbon nanotubes Mg-Cd hydroxyapatite (CNTs/(Mg-Cd)HAP) composites were synthesized by a co-precipitation method. The synthesized sorbents were characterized using BET surface area measurements, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). They have possessed specific surface area of 34.85 and 60.41 m2 g–1 for (Mg-Cd)HAP and CNTs/(Mg-Cd)HAP, respectively. Furthermore, the synthesized sorbents were applied in removal of Eu(III) ions from aqueous solutions. Sorption performance of the synthesized sorbents towards Eu(III) ions was studied under different sorption parameters such as equilibration time, sample mass, solution pH and ionic strength. Sorption of europium reached equilibrium within 6 h at pH 2.5. The maximum sorption capacity (Qmax) was 137.31 and 151.47 mg g–1 for sorption of Eu(III) onto (Mg-Cd)HAP and CNTs/(Mg-Cd) HAP, respectively. Kinetically, the sorption process followed the pseudo-second-order model and both film and pore diffusions participated in ruling the diffusion of Eu(III) ions. Equilibrium sorption data of Eu(III) were analyzed using Freundlich and Langmuir isotherm models. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) for sorption of Eu(III) onto the synthesized sorbents were determined and the reaction is found to be feasible, spontaneous and endothermic process.

Gamma-induced radiation polymerization of kaolin composite for sorption of lanthanum, europium and uranium ions from low-grade monazite leachate

Gamma radiation polymerization method was used for the modification of kaolin to produce (poly acrylamide-acrylic acid)-Kaolin (PAM-AA-K). Monazite ore is one of the main resources of uranium and lanthanide elements, therefore, this work focused on sorption of uranium, lanthanum and europium ions from low grade monazite leachate. The removal percent for Eu3+, La3+ and UO2 2+ are 94.6, 91.6 and 73.4%, respectively. Monolayer capacity of Eu3+, La3+ and UO2 2+ were found to be 54.64, 45.87 and 37.59 mg/g, respectively. The sorption mechanism of lanthanum and europium ions on PAM-AA-K composite mainly takes place as Ln(OH)2+, and for uranium as uranyl ion, UO2 2+.

Clay-salt slimes of the JSC \u201cBelaruskali\u201d as potential engineering barriers in the radioactive waste repositories: sorption of Cs(I), Sr(II), Eu(III) and Am(III)

Results of sorption of caesium(I), strontium(II), europium(III) and americium(III) ions on the aluminosilicates separated from the clay-salt slimes (CSS) depending on the contact time, pH, initial metal concentration are presented. CSS 1A and CSS 1B sorbents appear to be sufficiently chemically and radiation stable for practical application in treatment of the radioactive wastewaters.

Sorption of europium onto diethylenetriaminepentaacetic acid based silica dioxide: kinetics, isotherm, thermodynamics

As a long-lived radionuclide, americium (Am) in spent nuclear fuel is a tricky isotope that partially impedes nuclear waste reclamation. This study dealt with sorption of europium (Eu) as a nonradioactive surrogate for Am onto diethylenetriaminepentaacetic acid based SiO2 (DTPA-SiO2). Equilibrium isotherms, kinetics, thermodynamics and pH experiments were investigated batch wise. The sorption strongly depended on pH. The maximal europium sorption capacity reached 192.42 mg/g, much higher than any currently reported. Thermodynamic parameters suggested the sorption was a spontaneous, exothermic and entropy increase process. Regeneration results showed the acceptable loss in the sorption ability after five circulations, indicating good reusability.

Ionic liquid modified silica gel for the sorption of americium(III) and europium(III) from dilute nitric acid medium

The imidazolium bis(2-ethylhexyl) phosphate moiety was chemically attached on silica gel by chemical modification. The resulting product ([SG-Im]+ [DEHP]−) was characterized by FT-IR spectroscopy, thermogravimetry and elemental analysis. The sorption behavior of Am(III) and Eu(III) on [SG-Im]+ [DEHP]− was studied from dilute nitric acid medium for the separation of Am(III) and Eu(III) from aqueous waste. The effect of time, concentrations of nitric acid and europium in aqueous phase on the distribution coefficient (K d) was studied. The study indicated the possibility of using modified silica for the separation of Eu(III) from Am(III) with high separation factors (>50 at 0.1 M HNO3).

Sorption of Europium (III) Ions by Natural Mordenite-Containing Tuff

Sorption of Europium (III) Ions by Natural Mordenite-Containing Tuff

Merrifield resin modified with thiacalixarene-tetraphosphonates: synthesis, characterization and europium sorption

Merrifield resin modified with thiacalixarene-tetraphosphonates: synthesis, characterization and europium sorption

Elaboration of Impregnated Composite for Sorption of Europium and Neodymium Ions from Aqueous Solutions

Silica-based urea–formaldehyde (SiO2/UF) composite material was prepared and impregnated with organophosphorus extractant, namely; 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester, for removal of Eu3+ and Nd3+ from aqueous solutions. The sorption capacity of the impregnated SiO2/UF for Eu3+ and Nd3+ were determined and found to be 3.1 and 2.8meq/g, respectively. Pseudo-second-order kinetic model is applicable and the sorption process is controlled by intra-particle diffusion mechanism. The values of thermodynamic parameters indicated that the sorption process is spontaneous and has endothermic nature. The prepared impregnated composite is an efficient sorbent media and recommended for removal of some lanthanide elements from aqueous solution.

Novel Diglycolamic Acid Functionalized Iron Oxide Particles for the Mutual Separation of Eu(III) and Am(III)

Iron oxide (Fe3O4) particles functionalized with diglycolamic acid (Fe-DGAH) were synthesized and characterized by TG-DTA, X-Ray diffraction,1H NMR, and scanning electron microscopy (SEM). The extraction behavior of Am(III) and Eu(III) in Fe-DGAH was studied from dilute nitric acid medium to examine the feasibility for the mutual separation of trivalent actinides and lanthanides using Fe-DGAH. For this purpose, the effect of various parameters such as the duration of equilibration and concentrations of europium, nitric acid, and diethylenetriaminepentaacetic acid (DTPA) in the aqueous phase on the distribution ratio (Kd) of Am(III) and Eu(III) was studied. The conditions needed for the efficient separation of Am(III) from Eu(III) were optimized using DTPA. The distribution ratio of ˜104 mL/g was obtained for both Am(III) and Eu(III) at pH 3, and it decreased with an increase in the concentration of nitric acid. However, a separation factor of Eu(III) over Am(III) of ˜150 was achieved in the presence of DTPA. Rapid sorption of metal ions in the initial stages of equilibration followed by the establishment of equilibrium occurred within 2 h. The sorption data were fitted to the Langmuir adsorption model, and the apparent europium sorption capacity was determined to be ˜50 mg/g. The study indicated the feasibility of using Fe-DGAH particles for magnetic separation of Eu(III) from Am(III) with high separation factors.

Sorption of americium(III) and europium(III) from nitric acid solutions by a novel diglycolamide-grafted silica-based resins: Part 2. Sorption isotherms, column and radiolytic stability studies

Abstract Two novel diglycolamide-grafted silica-based resins (DGSRs) were used for the sorption of trivalent actinides and lanthanides from 3 M nitric acid solutions. The sorption of Am(III) onto the resin containing one diglycolamide (DGA) moiety (DGSR-I) was less efficient than the resin containing two DGA moieties (DGSR-II) with Lagergren first order rate constants of (1.20 ± 0.03) × 10 –3 s –1 and (2.01 ± 0.05) × 10 –3 s –1, respectively. The maximum sorption of Eu(III) (used as a representative of the trivalent lanthanide/actinide ions in radioactive wastes) was 10.4 ± 1.1 mg g –1 and 13.9 ± 1.3 mg g –1 by the DGSR-I and DGSR-II, respectively. The sorption of Eu(III) on the grafted silica resins followed the Langmuir monolayer sorption phenomenon with sorption energies of 16.5 ± 2.05 and 17.8 ± 1.6 kJ mol –1 for DGSR-I and DGSR-II, respectively. Column experiments revealed that the breakthrough capacity of Eu(III) on the DGSR-II column was higher than that on the DGSR-I column. Efficient elution could be achieved with a 0.01 M EDTA solution. The radiolytic stability of the resins was ascertained by exposing the resins to a gamma ray dose up to 1030 kGy resulting in a decrease of the K d values with about 50%; at doses <500 kGy the K d values remained unaffected.

Zirconium organophosphonates as high capacity, selective lanthanide sorbents

Novel and versatile zirconium organophosphonate coordination networks have been developed as sorbent platforms via simple, low-temperature hydrothermal reactions of zirconium propoxide with amino tris(methylene phosphonic acid) (ATMP). The resulting materials exhibited hierarchical porosity and possessed exceptional selectively for lanthanide elements over mono- and divalent metal ions during competitive sorption experiments in 0.1MHNO3, as well as modest intra-lanthanide selectivity. As such, the present materials have potential as solid phase extractants for lanthanide separations in applications including mining, radioactive waste treatment and environmental remediation. Lanthanide sorption was shown to occur via uncoordinated PO groups in the ATMP molecule. The structure, porosity and sorption properties of the coordination network platform could be tuned through varying the molar ratio of phosphorus to zirconium. Interestingly, the sample with the lowest surface area (<2m2/g) demonstrated the highest sorption capacity. Optimal compositions demonstrated europium sorption with fast kinetics and very high capacities of up to 0.63g/mgmin and 60mg/g respectively. As such, these highly stable zirconium organophosphonates, prepared from inexpensive precursor chemicals using one-pot methods, perform comparably to costly commercially available polymer resins.

Studying the sorption properties of a clinoptilolite-containing tuff with respect to europium(III) ions

The kinetic laws of sorption of europium(III) ions from sulfate solutions by a clinoptilolite-containing tuff are studied. The kinetic parameters of sorption process are determined and absorption isotherms are constructed for europium ions. It is found that both external and internal diffusion are rate-limiting steps, and europium is completely extracted from dilute solutions (<0.0025 m).

Kinetic investigation for sorption of europium and samarium from aqueous solution using resorcinol–formaldehyde polymeric resin

Kinetic study for Eu3+ and Sm3+ sorption on resorcinol–formaldehyde (RF) polymeric material has been performed using batch method. The sorption process of Eu3+ and Sm3+ was carried out at different contact time, pH of medium, initial ion concentration and temperature. The experimental data indicated that, RF could be used as an efficient sorbent for Eu3+ and Sm3+. The sorption kinetic for Eu3+ and Sm3+ onto RF polymeric resin takes about 1 h to reach equilibrium which is considered as a fast kinetic process. Sorption results were fitted using different kinetic models such as pseudo-first-order, pseudo-second order and intraparticle diffusion models. The results indicated that the sorption of both Eu3+ and Sm3+ onto RF resin is highly fit with the pseudo-second order model. Moreover, the obtained results showed that the maximum separation factor between Eu3+ and Sm3+ was obtained at pH 3. Therefore, RF resin is considered as a promising material for sorption of Eu3+ and Sm3+ form aqueous solution.

Sorption of europium by malt spent rootlets, a low cost biosorbent: effect of pH, kinetics and equilibrium studies

The uptake of lanthanide elements by naturally abundant materials, is a matter of great economic and environmental interest. This study is an exploration of the potential utilization of malt spent rootlets (MSR), which are by-products of malting process, for a cost effective pre-concentration of Eu(III). The effect of solution pH, contact time and initial concentration under constant ionic strength and temperature were studied. Kinetic data were applied to pseudo-first, second order and Elovich equations, as well as intra-particle diffusion model. Pseudo-second order and Elovich equation seem to fit our data equally well, whereas diffusion contributes to the whole process. Equilibrium data were evaluated using Langmuir, Freundlich and Dubinin-Radushkevich equations. According to Langmuir model, which fits the data better, europium maximum capacities for MSR and active carbon were found 156 and 86 mg/g respectively, indicating that MSR is a promising biosorbent.