Adsorption Of Th Research Articles

Effective synthesis and characterization of citric acid cross-linking of modified ferrous metal-organic framework and chitosan nanocomposite sponge for Th(IV) elimination: Adsorption isotherms, kinetic analysis, and optimization by Box-Behnken design

This research presents a novel nanocomposite of ferrous metal-organic framework (Fe(II)-MOF) that has been encapsulated with chitosan matrix, leading to the development of a new adsorbent referred to as NH2-Fe(II)-MOF@CSC composite sponge. This composite sponge has shown effectiveness in removing radioactive thorium (IV) contamination from water sources. The adsorbent underwent characterization using techniques including FTIR, PXRD, BET analysis, and SEM. The adsorbent has a high surface area of 1360.8 m2/g. The most effective conditions for adsorbing Th(IV) were found to be a pH of 5, using 0.02 g of adsorbent dose per 25 mL, and maintaining a contact time of 100 min. The composite sponge demonstrated an impressive maximum adsorption capacity of 618.8 mg/g for Th(IV). The adsorption process was fitted to Langmuir isothermally and kinetically fitted to pseudo-second-order. Nonetheless, the relatively low adsorption energy of 6.22 kJ/mol suggests that the main adsorption mechanism is physisorption, which is marked by weaker van der Waals forces. This discovery could have implications for the material's potential for easy regeneration. In the analysis of the influence of temperature on the adsorption of Th(IV), it was discovered that the adsorption process is endothermic because the positive ΔHo value was 24.48 kJ.mol−1. Furthermore, a positive ΔSo value of 87.46 J.mol−1 K−1 suggests the existence of disorder at the solid-solution interface. Conversely, a temperature rise resulted in a higher negatively charged ΔGo, indicating that the adsorption process is spontaneous. The research also examined the mechanism of interaction, such as π-π interaction, hydrogen bonding, pore filling, and electrostatic interaction. It was noted that the adsorbent can be efficiently used for a maximum of six cycles, demonstrating its economic viability. The adsorption outcomes were optimized using the Box Behnken design (BBD).

Preparation of Quaternary Ammonium Separation Material based on Coupling Agent Chloromethyl Trimethoxysilane (KH-150) and Its Adsorption and Separation Properties in Studies of Th(IV).

In this research, the authors studied the synthesis of a silicon-based quaternary ammonium material based on the coupling agent chloromethyl trimethoxysilane (KH-150) as well as its adsorption and separation properties for Th(IV). Using FTIR and NMR methods, the silicon-based materials before and after grafting were characterized to determine the spatial structure of functional groups in the silicon-based quaternary ammonium material SG-CTSQ. Based on this, the functional group grafting amount (0.537 mmol·g-1) and quaternization rate (83.6%) of the material were accurately calculated using TGA weight loss and XPS. In the adsorption experiment, the four materials with different grafting amounts showed different degrees of variation in their adsorption of Th(IV) with changes in HNO3 concentration and NO3- concentration but all exhibited a tendency toward anion exchange. The thermodynamic and kinetic experimental results demonstrated that materials with low grafting amounts (SG-CTSQ1 and SG-CTSQ2) tended to physical adsorption of Th(IV), while the other two tended toward chemical adsorption. The adsorption mechanism experiment further proved that the functional groups achieve the adsorption of Th(IV) through an anion-exchange reaction. Chromatographic column separation experiments showed that SG-CTSQ has a good performance in U-Th separation, with a decontamination factor for uranium in Th(IV) of up to 385.1, and a uranium removal rate that can reach 99.75%.

Feasibility and recyclability study of magnetic activated carbon derived from palm tree fibres (AC/Fe3O4) in thorium (IV) removal from aqueous solution

ABSTRACT Entrance and penetration of Th (IV) into the human body can lead to many health effects. The main objective of the current study was to demonstrate the elimination of Th (IV) from aqueous solutions using magnetic activated carbon derived from palm tree fibres (AC/Fe3O4) as an efficient and environmentally friendly adsorbent. The Box-Behnken Design (BBD) under the response surface methodology (RSM) was used to determine the impact of independent parameters and optimal conditions. The optimal conditions were achieved in Th (IV) concentration of 11 mg/L, contact time of 30 min, pH 4, and the adsorbent dose of 3.12 g/L (maximum adsorption of Th (IV): 96.60%). The AC/Fe3O4 had good recyclability and efficiency to remove Th (IV) from the aqueous environment.

Adsorption of thorium (IV) from aqueous solutions using mesoporous TiO2: Kinetics, isotherm and thermodynamics

Thorium is considered as a promising resource for the production of nuclear power, with its abundance in the Earth's crust offering potential for sustainable energy generation to fulfill upcoming energy needs. As a fertile material, thorium has the capability to be converted into fissile uranium-233, which is essential for sustaining nuclear chain reactions. Therefore, the extraction of thorium from the Earth's crust is imperative for its utilization as fuel in nuclear reactors. This study presents the synthesis of titanium dioxide with a mesoporous structure using the solvothermal method for extracting Th(IV) from aqueous solutions. Batch adsorption experiments were carried out to evaluate the impact of solution pH, adsorption kinetics, adsorbent dosage, initial Th(IV) concentration, and temperature. The adsorption process is influenced by the pH, showing a maximum adsorption capacity of 101.4 mg per gram of mesoporous TiO2 adsorbent (MTA) at an initial Th(IV) concentration of 400 mg L−1 at pH 4.0. Results indicate a significant correlation with the pseudo-second-order and Freundlich adsorption isotherm models. Temperature-dependent investigations revealed that the adsorption of Th(IV) is spontaneous at room temperature and increases with higher temperatures (endothermic process). Moreover, the study highlights the rapid kinetics of Th(IV) adsorption by MTA, making it a favorable choice for upscaling the extraction process of Th(IV). In conclusion, the results suggest MTA as a promising adsorbent for the removal of Th(IV) from aqueous solutions.

Insight to the batch reactor design and sorption potential profiling of polymer grafted chitosan embedded silanated halloysite for Th(IV) recovery from aqueous system

The removal of Th(IV) from wastewater stands as a pivotal step towards advancing cleaner energy, mitigating radioactive contamination, and fostering sustainable nuclear fuel practices. In this research endeavor, a pioneering adsorbent, polymethacrylic acid-grafted-chitosan embedded silanated halloysite (PMAA-g-CT/sHNT), has been synthesized to effectively remove Th(IV) from aqueous solutions. The study meticulously optimized process parameters for the adsorption of Th(IV) onto PMAA-g-CT/sHNT, employing both pseudo-second-order and intra-particle diffusion models. Remarkably, the Langmuir isotherm model exhibited exceptional fitting, revealing a remarkable Th(IV) uptake capacity of 320.99 mg/g at 30 ℃. Thermodynamic analyses underscored the spontaneous and endothermic nature of Th(IV) sorption, as evidenced by the negative ΔG° (-43.73 kJ/mol), positive ΔH° (398.71 kJ/mol), and positive ΔS° (0.0123 kJ/mol/K) values. The desorption process exhibited significant promise, with over 90% Th(IV) recovery even after four cycles of use. In a stride towards practical applicability, a two-stage batch reactor has been devised for commercial implementation of the adsorbent, with operating lines delineated. The efficacy and practicality of the sorbent were further corroborated through investigations conducted using simulated seawater, where a dosage of 2.5 g/L proved optimal for treating 1 L of water. This groundbreaking research not only elucidates the potential of PMAA-g-CT/sHNT as a potent Th(IV) adsorbent but also heralds a promising avenue for addressing critical challenges in wastewater treatment and nuclear waste management.

Innovative g-C3N4/AX composite electrode for effective thorium elimination from aqueous solutions

Electrosorption is a technique that combines electrical and adsorption processes and has been established to displace Th(IV) from aqueous solutions. The present study successfully synthesised a novel electrode, where graphitic carbon nitride was modified with amidoxime amidoxime groups (g-C3N4/AX) via the hydrothermal method. The batch experiments conducted in this study revealed that the g-C3N4/AX electrode possessed a favourable thorium adsorption capacity of 275.74 mg.g−1 and a swift elimination equilibrium of within 30 min. Furthermore, the removal efficiency at − 1.0 V (84.46 %) of the electrode was almost threefold greater than the removal efficiency at open circuit potential (24.09 %). The results were due to the free electrical charges on the g-C3N4/AX electrode, which induced the electrical driving force and facilitated the adsorption of Th(IV) ions onto the g-C3N4/AX surface. The shifted bands from the Fourier transform-infrared (FT-IR) spectrum post-electrosorption demonstrated a substantial complexation of Th(IV) with the amine groups of amidoxime and g-C3N4. A significant transference in energy band peaks was also observed during the XPS assessment, indicating that the electrosorption process included oxygen (O), carbon (C), and nitrogen (N) species. In the practical real wastewater involving rare earth residue, which contains Ce, La, Nd and Pr ions, g-C3N4/AX exhibited good capabilities in selectively adsorbing Th(IV). The electrode synthesised in this study also exhibited the ability to regenerate with a reasonable ∼ 80 % removal ratio after five runs. The results indicated that the amidoxime-modified graphitic carbon nitride electrode demonstrated a good potential in removing thorium from aqueous solutions via electrosorption applications.

Removal of Th(IV) from groundwater by adsorption onto nano-Kaolin and nano-Kaolin/MnFe2O4 composite

ABSTRACT The adsorption of Th(IV) ions by nano-Kaolin and nano-Kaolin/MnFe2O4 composite were studied as a function of pH, sorbent mass, time, and temperature. Kinetic data was fitted to pseudo second-order model, and the maximum value of the adsorption capacity of the monolayer (qm) for nano-Kaolin and nano-Kaolin/MnFe2O4 was at pH 3. The Langmuir, Freundlich, and Dubinin–Radushkevich isotherm equations were fitted to the adsorption data and the proper constants were calculated. From adsorption isotherms at different temperatures, ΔH° (endothermic), ΔG° (favourable), and ΔS° (positive) were calculated.

Selective recovery of Th(IV) from radioactive rare earth waste residue by utilizing MoS2-modified ion-absorbed type rare earth tailings

In the process of extracting ion-absorbed rare earth ore (IREO), the production of radioactive waste is a major environmental concern. To address this issue, MoS2 was used to modify ion-absorbed rare earth tailings (RET) to synthesize a novel MoS2@RET composite material for the effective handling of radioactive waste generated in IREO separation industry. The composite material was thoroughly characterized using various analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TG), Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and energy dispersive spectroscopy (EDS). By optimizing the operating parameters, the optimal experimental conditions were determined to be pH = 3, contact time = 60 min, liquid-solid ratio = 6 g/L, and initial concentration = 150 mg/L. The adsorption data fitted well with the pseudo second-order rate model. The thermodynamic parameters concerning the adsorption of Th(IV) were analyzed and computed. Langmuir isotherm model is a more fitting choice for the adsorption process compared to the Freundlich isotherm model. MoS2@RET was used in the acid leachate of IREO waste residue, achieving the separation of Th and rare earth successfully. The mechanism of Th(IV) adsorption by MoS2@RET was investigated, revealing that the adsorption process involves electrostatic interactions, chemical bonding, and redox reactions. The above research results indicate that MoS2@RET composite materials have application potential in the sustainable treatment of IREO radioactive waste.

Adsorption of Th(IV) in nitric acid medium by a new poly(4-vinylpyridine) resin

Adsorption of Th(IV) in nitric acid medium by a new poly(4-vinylpyridine) resin

Adsorption of Th(IV) ions from aqueous solutions by ZnO functionalized graphene oxide

Abstract Graphene oxide (GO) and zinc oxide (ZnO) were synthesized via the Tour’ and sol-gel methods, respectively. Adsorption potentials of Th(IV) ions were investigated with the functionalization of GO with ZnO nanoparticles (GO-ZnO) and compared with the GO. Studies concerning factors affecting the adsorption process, kinetics, adsorption isotherms, and thermodynamic properties were carried out. In this study, the optimum pH for the adsorption of Th(IV) ions is 3.0, and quickly reaching equilibrium is an indication of the high efficacy of the sorbent. A pseudo-second order adsorption model fits the kinetic data well. Experimental results were compared with Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models. These results show that the Langmuir model fits the data well. Measured thermodynamic parameters, Gibbs free energy change (ΔG°), enthalpy change (ΔH°), and entropy change (ΔS°) indicate that the adsorption of Th(IV) on GO−ZnO is spontaneous and endothermic in nature. According to the linear fit in the Langmuir isotherm model, the maximum adsorption capacity of GO and GO-ZnO at 298 K occurs at 109.89 mg/g and 243.90 mg/g, respectively. The results show that decoration with ZnO nanoparticles is a good method to improve the adsorption capacity of GO for Th(IV) removal.

γ-Resistant Microporous CAU-1 MOF for Selective Remediation of Thorium.

A simple solvothermal method was used to synthesize a metal-organic framework (MOF) with an Al metal entity, viz., CAU-1 NH2. The synthesized MOF was characterized using different techniques like X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy (SEM), field emission SEM (FE-SEM), transmission electron microscopy, small-angle X-ray scattering, positron annihilation lifetime spectroscopy, and X-ray photoelectron spectroscopy. The radiation stability was evaluated by irradiating the material up to a cumulative dose of 2 MGy using 60Co for the first time. The studies showed a remarkable gamma irradiation stability of the material up to 1 MGy. The porosity and surface area of the synthesized MOF were determined by Brunauer-Emmett-Teller, which showed a high specific surface area of 550 m2/g. The pH dependence study of Th uptake from an aqueous solution was performed from pH 2-8, followed by adsorption isotherm and adsorption kinetics studies. These results revealed that the Langmuir and pseudo-second-order kinetic models can be well adapted for understanding the Th uptake and kinetics, respectively. The synthesized MOF exhibited an ∼404 mg/g thorium adsorption capacity. Selectivity studies of adsorption of Th w.r.t. to U and different metal ions such as Cu, Co, Ni, and Fe showed that Th gets adsorbed preferentially as compared to other metal ions. In addition, the MOF could be used multiple times without much deterioration.

Preparation and potential application of amino-functionalized titanosilicates to removal of Th(IV) in aqueous solutions: optimization using response surface methodology (RSM)

Abstract Mesoporous titanosilicates (TiSil) with a size of almost 25 nm were prepared by an alkali-assisted hydro-thermal route, as an choice for developing efficient adsorbents of Th(IV) ions. TiSil were functionalized with the amino functional group (-NH2) from 3-aminopropyltriethoxysilane (APTES) by post-preparation method. The obtained amino-grafted titanosilicates (TiSilNH2) were characterized by Scanning Electron Microscopy (SEM), Brunauer–Emmett–Teller (BET), X-ray Diffraction (XRD) and Fourier-Transform Infrared Spectroscopy (FTIR) techniques. Adsorption of Th(IV) ions on TiSilNH2 was examined in aqueous solution. Response surface methodology (RSM) based on central composite design (CCD) was applied to optimize the four essential process variables namely initial pH and initial concentration of Th(IV) ions of aqueous solution, amount of adsorbent, and adsorption process temperature for the Th(IV) removal. The adequacy of the model was investigated, and it was deemed to be statistically significant. The optimal predicted adsorption capacity of TiSilNH2 for Th(IV) ions was 83.04 mg/g and the actual value was 84.8 mg/g. The equilibrium adsorption data were fitted to Langmuir, Freundlich, Dubinin–Radushkevich and Temkin isotherm models. The equi-librium data were best re-presented by Langmuir isotherm model, showing maximum monolayer adsorption capacity of 87.71 mg/g. The thermodynamic parameters indicated that the Th(IV) adsorption on the TiSilNH2 was a spontaneous, and endo-thermic process at the studied temperatures and occurred via physisorption. Adsorbent recovery by using 0.5 M HNO3 solution for adsorbent reuse indicated that the adsorbent was regenerable and could be employed frequently.

Adsorption of Th(IV) on glutaraldehyde cross-linked N-(4-Aminobenzoyl)-ʟ-glutamic acid modified chitosan

Adsorption of Th(IV) on glutaraldehyde cross-linked N-(4-Aminobenzoyl)-ʟ-glutamic acid modified chitosan

Synthesis and characterization of graphene oxide/alginate and application of central composite design in the adsorption of Th(IV) on the nanobiocomposites

Abstract In this study, graphene oxide and aginate were used to synthesis of nanobiocomposites under different synthesis conditions and the used to investigate the adsorption properties of Th (IV) ions from aqueous solutions. BET surface area, SEM and TEM images, FT-IR spectrometry, XRD techniques were used for the characterization of the adsorbents. In batch adsorption experiments, parameters affecting the adsorption efficiency such as solution pH, contact time, Th (IV) concentration and temperature were investigated using central composite design (CCD). ANOVA (analysis) analysis at the 95% confidence interval of the model applied for the experimental design and the compatibility of this model with the experimental findings were examined. The relevance of the model for the nanobiocomposite prepared by the 1st method is that the P value is <0.05 and the model F value is 23.77 and 39.45 with the 2nd method, respectively. These results show that the regression for this method is statistically high. The correlation coefficient (R 2), which was 95.69% for the 1st method and 97.36% for the 2nd method, indicates a high coordination between the observed values and the estimated values. According to the CCD results, it has been observed that the main effects of the adsorption process with the materials obtained by the 1st method are in the direction of increasing the concentration, while pH, time and temperature do not have a statistically significant effect. In the adsorption process with the materials obtained by the 2nd method, it was observed that the concentration, time and temperature caused an increasing effect. Langmuir, Freundlich and Dubinin–Radushkevich isotherms were used to determine the adsorption model and the constants related to these isotherms were calculated. In addition, the adsorption process was also investigated in terms of thermodynamics.

Highly efficient extraction of thorium from aqueous solution by 2-carboxyethylphosphonic acid-functionalized chitosan xerogel

Efficient separation and enrichment of thorium from aqueous solutions is an important subject in the field of energy and ecological environment. In this study, a novel polymer-based xerogel was prepared by a crosslinking reaction of 2-carboxyethyl phosphonic acid functionalized chitosan(CCS-TCEP) and was applied to the adsorption of Th(IV) ions. The maximum adsorption capacity of CCS-TCEP could reach 311.6 mg/g with an excellent selectivity due to the abundant binding sites for thorium provided by TCEP. Moreover, this material has a high adsorption rate and the adsorption equilibrium could be reached within 60 min. After 5 cycles of reuse, the adsorption capacity of CCS-TCEP still retained more than 80 % of its initial value. Furthermore, the extraction mechanism of CCS-TCEP for Th(IV) ions was also analyzed in detail by FT-IR, XPS and DFT calculation. This study indicates that CCS-TCEP can be used as a potential adsorbent for efficient extraction of thorium from aqueous waste.

Revealing the role of oxygen-containing functional groups on graphene oxide for the highly efficient adsorption of thorium ions

Oxygen-containing functional groups on the surface of carbon materials can promote the adsorption capacity of radioactive thorium ions (Th(IV)), but their effect on the adsorption of Th(IV) has not been systematically revealed. Herein, to elucidate the nature of oxygen-containing group-mediated Th(IV) adsorption, a series of graphene oxide nanoflakes (GONFs) with different contents of oxygen-containing groups on the surface were prepared. The experimental results showed that the high adsorption of Th(IV) not only resulted from the oxygen content, but also was related to the type of oxygen-containing functional groups on GONFs. Subsequent density functional theory (DFT) calculations revealed that the high adsorption capacity for Th(IV) originated from the oxygen-containing groups and their adjacent activated sp2 carbon atoms. More importantly, the coordination of Th(IV) with oxygen functional groups induced the aggregation of GONFs, leading to the sedimentation of GONFs, which facilitated the separation of adsorbents and enabled the GONFs to be a more practical adsorbent for Th(IV). This work deepens our understanding of the role of oxygen-containing groups on Th(IV) adsorption and provides a new strategy for the design and synthesis of high-performance surface oxygen-containing carbon-based adsorbents with practical application potential.

Removal of Th(IV) from aqueous solution with modified silica gel by 4-hydroxy-N ′ - ((thiophen-2-yl) methylene)benzohydrazide schiff base

ABSTRACT In this study, SiCPMS@L solid adsorbent was prepared using 4-Hydroxy-N ′- ((Thiophen-2-yl)methylene)benzohydrazide Schiff base for thorium(IV) removal from aqueous solution, and the structure of the solid adsorbent was characterized by FTIR, SEM, elemental analysis, and BET surface analysis methods. Solution pH, initial thorium concentration, contact time, adsorbent dose, and temperature parameters affecting the adsorption of Th(IV) ions with SiCPMS@L adsorbent were examined, and optimum uptake conditions were determined. The effective initial pH for adsorption was found to be 4.0. The binding sites on SiCPMS@L solid adsorbent were saturated using an initial Th(IV) concentration of 16.0 mg/L. 30 minutes was determined as the optimum contact time when the adsorption equilibrium was established. The optimum adsorbent dose for SiCPMS@L was determined as 1.0 g/L. At optimum conditions, adsorption efficiency and adsorption capacity values for SiCPMS@L adsorbent were respectively; 97.4% ± 0.1 and 15.6 ± 0.1 mg/g were obtained. The calculated thermodynamic parameters ∆S°, ∆G° and ∆H° showed that the Th(IV) sorption process is thermodynamically advantageous, spontaneous and endothermic. Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherms for removal of Th(IV) ions with SiCPMS@L solid adsorbent were investigated and found to be compatible with Langmuir isotherm.

Adsorption of Th and Pa onto particles and the effect of organic compounds in natural seawater

Adsorption of Th and Pa onto particles and the effect of organic compounds in natural seawater

Highly efficient sorption of thorium (IV) onto a ternary magnetic TiO2/Fe3O4/GO nanocomposite

Abstract A recyclable TiO2/Fe3O4/GO (TFGO) ternary magnetic nanocomposite was developed for the adsorption of Th (IV) from an aqueous media. The nanocomposite was prepared using a simple colloidal mixing technique. The TFGO nanocomposite was characterized by X-ray diffraction, Fourier transform infrared, thermal gravimetric analysis, scanning electron microscope and transmission electron microscope. The nanocomposite is conveniently isolated by applying an external magnetic field. Using batch procedures, the impact of adsorption process control parameters was examined. The maximum Th (IV) adsorption capacity of the TFGO nanocomposite was 29.97 mg/g at pH 2.5 with 92.31%, removal efficiency better than that of conventional adsorbents. The isothermal models of Langmuir and Freundlich were also applied to illustrate the adsorption of Th (IV) of aqueous solutions on TFGO. The thermodynamic parameters (ΔH°, ΔS° and ΔG°) of the adsorption process were also calculated. Furthermore, the experimental data from this adsorption process were adapted to the pseudo second order model rather than the pseudo first order model. TFGO nanocomposite exhibits outstanding recovery properties. So; due to highly adsorption potential of Th (IV), TFGO nanocomposite could be used in nuclear fuel accomplishments and for Th (IV) environmental pollution cleaning.

Highly efficient capture of Th(IV) from aqueous solutions using GO/TiO2 nanocomposite

An adsorbent GO/TiO2 nanocomposite has been synthesized and characterized. FTIR, XRD, TGA, TEM, SEM and EDX were used to characterize the prepared composite. In a batch method, the adsorption properties of the prepared composite against thorium ions were examined. Th(IV) adsorption kinetics study on GO/TiO2 suggests that the adsorption equilibrium attained within 240 min and depends on the pH value. The adsorption results were expressed mathematically by using Langmuir and Freundlich sorption models. The nanocomposite showed the highest Th(IV) adsorption of 292.32 mg/g at pH 2.5 and 25 oC. The thermodynamic results indicated a thermodynamically favorable, random and exothermic nature of the adsorption process. The obtained results demonstrate that GO/TiO2 nanocomposite can be regarded as a fast, effective and convenient water-based adsorbent for adsorption of Th(IV). This study suggests that nanocomposite can be a promising candidate for the removal of Th(IV) from aqueous solution.