Cesium Adsorption Research Articles

Sugarcane bagasse decorated by metal (Fe3+/Cu2+) ferrocyanide for effective removal of cesium from aqueous solutions

In this work, we convert the biowaste materials (sugarcane bagasse) into wealth materials via combination with metal ferrocyanide through two steps to prepare (SCB-M-FC) composite for cesium removal from aqueous solutions. Firstly, SCB was modified to be amino silane (SCB-NH2) to provide amine binding sites. Secondly, the metal (M = Fe3+or Cu2+) ferrocyanide (FC) nanomaterials grow in situ on the surface of the modified -SCB to yield SCB-M-FC. Various techniques were used to characterize the prepared composite materials before and after the adsorption of cesium. The adsorption behavior of Cs+ by SCB, SCB-NH2, and SCB-M-FC under different conditions was studied and compared. We observed that the SCB-Cu-FC presents the experimental adsorption capacity for Cs+ (126.0 mg/g). Additionally, dynamic system for cleaning cesium from polluted water was also investigated. The excellent selective removal of Cs by SCB-M-FC was escorted by the liberation of K+ and diffusion mechanisms. The SCB-Cu-FC nanocomposite was found to be appropriate for the practical removal of cesium from contaminated aqueous solution.

Irrversible cesium adsorption capacity of granite-origin soil

Irrversible cesium adsorption capacity of granite-origin soil

An Evaluation of Cesium Removal from Simulated Radioactive Contaminated Soil with a Magnetized Zeolite Derived from Anthracite

The magnetized zeolite with an optimized conversion rate of 53% can be readily synthesized from industrial anthracite using a water-based method. The highly porous structure of ferromagnetism zeolite demonstrates robust magnetic properties with a magnetite content of 12–15%, satisfying adsorbent separation and recycling through magnetic cylinder rotating and vibrating separation. A cesium adsorption and removal efficiency as high as 99.92% with a corresponding adsorbent recovery ratio of up to 96.36% can be achieved for the simulated cesium-contaminated soil with a water content of 20% and a cesium content of 1% with an adsorbent-to-contaminated soil ratio of 1:2. Adsorption and magnetic separation technology with magnetized zeolite synthesized from anthracite exhibited a high cesium removal rate and zeolite recovery ratio, demonstrating promising application potential in treating radioactive waste soils and robust and economically viable engineering feasibility.

Potential Errors in Cation Exchange Capacity Measurement in Soils Amended with Rock Dust: Two Case Studies

ABSTRACT The use of rock dust in agriculture has increased worldwide and particularly in Brazil since its regulation by Law 12.890 (2013). However, some inconsistent results in standard chemical analysis of soils amended with rock dust have drawn attention, and among them, cation exchange capacity (CEC). This paper evaluates the increase in sum of bases (SB) and CEC of two soils amended with commercial rock dust (magnesium silicate), measured by four methods: ion exchange resin, potassium chloride (KCl), compulsive exchange and cesium adsorption. The maximum possible increase of SB in the soil was estimated based on the total chemical analysis of the rock dust and compared to the measured CEC results. We concluded the resin method inflated the results, due to the dissolution of rock dust particles by the acid extraction used to recover the adsorbed cations in resin beads. These extra cations caused overestimation of the sum of bases and consequently, of the estimated CEC. Among the methods used, direct CEC methods were more appropriate, as well as the KCl, since it does not employ acid extractions at any step. In addition, calculations based on the total chemical analysis of the rock dust can help to identify some of the cases in which the routine analysis is inflated by the dissolution of rock dust.

Chitosan-minerals-based composites for adsorption of caesium, cobalt and europium

Currently, there is a growing interest in the use of natural materials in various fields of science, technology and environmental protection due to their availability, low-cost, non-toxicity and biodegradability. Chitosan, natural clay of local origin, montmorillonite, zeolite, cross-linking agents (epichlorohydrin, sodium tripolyphosphate, glutaraldehyde) and plasticisers (glycerol) were used to synthesise composites. The composites were characterised by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction analysis (XRD) and scanning electron microscope (SEM), tested for their antibacterial activity and used in batch experiments to study the adsorption of caesium, cobalt and europium ions. The maximum capacities for adsorption of caesium, cobalt and europium on the composites were 1400 mg/g, 900 mg/g and 18 mg/g, respectively. The experimental data fit better the Langmuir isotherm model and indicate favourable monolayer adsorption of Cs+, Co2+ and Eu3+ at homogeneous sites of the composites. The experimental data were in better agreement with the pseudo-second-order non-linear kinetic model for most elements and adsorbents. Adaptive neuro-fuzzy inference system proved to be a practical tool with good performance and generalisation capability for predicting the adsorption capacity of composites for caesium, cobalt, and europium ions. It was found that the predicted data were very close to the experimental data.

A technological approach based on engineered nanoclay composites for cesium and iodine retention.

The development of effective and environmentally friendly methods for separating hazardous radionuclides from waste poses a significant technological challenge. 137Cs and 131I are among the most important radionuclides discharged into the environment by nuclear power plants. One of the best ways to eliminate them involves adsorption on clay minerals. In this regard, studies have demonstrated that organofunctionalized clay minerals are effective adsorbents. Thus, this study investigates the capability of organofunctionalized synthetic design clay minerals to jointly eliminate cesium and iodine. The adsorbents studied are a range of organofunctionalized clay minerals with alkylammonium cations of different alkyl chain lengths (2, 3 and 18) and some physical mixtures of raw clay minerals and octadecylammonium compounds. Organofunctionalized synthetic swelling highly charged micas are effective adsorbents for the simultaneous adsorption of cesium and iodine. In addition, the optimal system is a mixture of Na-M4 with octadecylammonium (50% w/w).

Adsorption and diffusion mechanism of cesium and chloride ions in channel of geopolymer with different Si/Al ratios: molecular dynamics simulation

Adsorption and diffusion mechanism of cesium and chloride ions in channel of geopolymer with different Si/Al ratios: molecular dynamics simulation

Effects of Cold Sintering on the Performance of Zeolite 13X as a Consolidated Adsorbent for Cesium.

Cold sintering, a novel low-temperature consolidation technique, has shown promising results in various inorganic materials. However, the application of this technique to nanoporous materials for energy and environmental fields is not yet fully understood. This study investigates the effects of cold sintering on the relative densities, compressive strengths, chemical durabilities, crystal structures, specific surface areas, and adsorption capacities of zeolites. Cold sintering at 200 °C achieved 10 to 20% greater densification than conventional high temperature (700 °C) sintering; however, the original nanoporous structure of dry cold sintered zeolite was not maintained. Introducing liquid agents during the cold sintering process resulted in reduced degradation of the SSA and increased densification. Using NaOH as the liquid agent increased the solubility of elements in zeolite, which promoted chemical mobility and achieved the highest relative density (96.7 ± 2.8%). However, soluble layers between the particles led to fragmentation, making it unsuitable for aqueous applications. Using H2O as the liquid agent resulted in a relative density of 90.4 ± 4.1% while maintaining the nanoporous properties and structural integrity of zeolite under water. The cesium adsorption capacity (19.0 ± 0.1 mg·g-1) was similar to that of conventional zeolite ion exchangers, indicating that cold sintering with H2O was an efficient, economical, and safer alternative to conventional high-temperature consolidation method. Our findings suggest that this cold sintering can be applied to other nanoporous materials, such as metal-organic frameworks and covalent organic frameworks, in separation, catalysis, and adsorption applications.

Evaluation of Soil Dissolved Radiocesium Using Caesium Adsorption Disks in Paddy Fields and Its Relationship with Brown Rice Radiocesium Concentration

交換性カリウム濃度がイネの放射性セシウム吸収に影響を与えない程度に高い条件では、玄米の放射性セシウム濃度は，土壌中の溶存態放射性セシウム量から精度よく予測できる。しかし，溶存態放射性セシウム量の実測には，大量の土壌溶液採取やろ過・濃縮等の多大な労力が必要である。そこで，亜鉛置換型プルシアンブルーを担持した吸着シートで土壌中の溶存態放射性セシウムを吸着し，シートに吸着した溶存態放射性セシウム量から玄米放射性セシウム濃度を簡易に予測することが可能か否かを検討した。表面をメンブランフィルターで被覆することにより土壌粒子の付着を防ぐ加工をしたセシウム吸着ディスクを現地水田の作土に2週間埋設し，溶存態放射性セシウムを回収した。吸着シートに回収された放射性セシウム量は，玄米放射性セシウム濃度と高い正の相関があった。分げつ期に吸着シートを埋設し，回収された放射性セシウム濃度を分析することで，大量の土壌溶液の採取や土壌理化学性の分析を必要とせず，玄米中放射性セシウム濃度を予測出来る可能性が示された。

Molecular dynamics study on the adsorption of radioactive ions by geopolymers

The construction of nuclear power plants necessitates careful consideration of the discharge and fixation of nuclear waste. Geopolymers are new cement-based materials (CBMs) with three-dimensional cage-like structures that enable effective nuclear waste fixation. In this work, the adsorption of radioactive caesium and strontium ions by sodium aluminosilicate hydrate (NASH) gel, the main component of geopolymers, was investigated using molecular dynamics simulations to obtain nanoscale insights into the ions’ interactions with the gel. The formation of strong ion–oxygen bonds allowed both ions to be effectively adsorbed on the NASH surface, but the adsorption ratio of strontium ions (17.2%) was slightly lower than that of caesium ions (21.0%). Because strontium ions are divalent, they can form stronger electrostatic interactions with water molecules and chloride ions, which hinders their approach to the interface. For the same reason, the diffusion coefficient of strontium ions in solution is lower than that of caesium ions. These results provide new insights into the nuclear waste fixation capacity of NASH gel and guidance for the design of new CBMs for radioactive waste disposal.

Marine halophilic archaeal isolate Halococcus sp. with emphasis on bioremediation of radionuclides through extracellular biomolecules

AbstractBACKGROUNDMarine archaea have gained special attention for their unique ability to survive in extreme salt concentrations. Some archaeal isolates have been found to thrive in the presence of radioactive contaminants. In this study, Halococcus sp. ENMS8 has been isolated from marine sediment sample with special emphasis on bioremediation of radionuclide cesium.RESULTSHalococcus sp. ENMS8 has the ability to remove 76.46% of cesium ions noted at a concentration of 100 mmol L−1 followed by 60.5%, 52.16% and 42.9% of cesium ion adsorption at concentrations of 150, 200 and 250 mmol L−1 Cs+, respectively. The minimal level of 4.43% of cesium adsorption was noted at 500 mmol L−1 concentration in the presence of 106 archaeal cells per milliliter. Similarly, adsorption of cesium (500 mmol L−1) at various concentrations of archaeal extracellular polymeric substances (EPS) has been shown to be 76.4% of Cs+ adsorption at 1 g L−1. The composition of extracted EPS from ENMS8 in the presence of CsCl and control has been estimated. Cesium adsorption was further confirmed with Fourier transform infrared spectroscopy, and scanning electron microscopy was used to obtain high‐resolution images of the surface topology of Halococcus sp. ENMS8 EPS in the presence of cesium. The crystallographic structure and properties of cesium were studied by energy‐dispersive X‐ray spectroscopy.CONCLUSIONThe present study concluded that Halococcus sp. ENMS8 can immobilize cesium through EPS in an eco‐friendly approach. © 2023 Society of Chemical Industry (SCI).

Comparison of Adsorbents for Cesium and Strontium in Different Solutions

Adsorption is an effective method to remove cesium and strontium from a solution. Although a variety of adsorbents has been reported, it is difficult to compare their adsorption properties due to different experimental conditions (such as solution concentration, volume, composition, temperature, etc.). In this paper, a series of adsorbents for the adsorption of cesium and strontium (ammonium phosphomolybdate, Prussian blue, sabite, clinoptilolite, titanium silicate) were synthesized and characterized using XRD, IR and SEM, and their adsorption performance in mixed solution (containing Li, Na, K, Cs, Ca, Sr and Mg ions, 1 mmol L−1), artificial seawater and salt lake brine were studied under the same conditions; in addition, the adsorption mechanism was elucidated. The results showed that ammonium phosphomolybdate has the largest adsorption capacity for cesium in the mixed solution. In artificial seawater and salt lake brine, Prussian blue displays the highest cesium adsorption capacity and the best selectivity. The multi-adsorption mechanisms are beneficial to the selective adsorption of Prussian blue in complex solutions. These results are useful for choosing adsorbents for cesium and strontium in applications.

Adsorption and separation of Cs(I) and Ba(II) from aqueous solution using zinc ferrite-humic acid nanocomposite

Reclaimable adsorbents have an essential role in removing radionuclides from waste streams. Herein, zinc ferrite-humic acid ZFO/HA nanocomposite was synthesized for effective cesium and barium adsorption. The prepared ZFO/HA nanocomposite was analyzed using analytical techniques including XRD, FTIR, EDX, and SEM. From kinetic studies, the mechanism adsorption process follows the second model. The isotherm studies clarified that the Langmuir model fit the adsorption of both ions onto the prepared sample, and the monolayer capacities are equal to 63.33 mg/g and 42.55 mg/g for Ba(II) and Cs(I), respectively. The temperature parameter was also studied, and the adsorption reaction was spontaneous and endothermic. The maximum separation between two ions was achieved at pH 5 (αCs/Ba = 3.3).

Adsorption mechanism and mass transfer modeling of cesium and europium ions adsorption onto hematite-loaded polyacrylamide-gel composite: Pore Volume and Surface Diffusion Model Approach

The overall adsorption rate of cesium (Cs+) and europium (Eu3+) ions onto hematite-loaded polyacrylamide-gel composite (HPAC) in single and binary pollutant systems was explained with diffusional model that takes into consideration both external mass transfer and intra-particle diffusion. The influence of changing system temperature on the overall adsorption rate of Cs+ and Eu3+ onto HPAC was studied. The fitting process of the experimental data with the three studied isotherm models (Langmuir, Freundlich and Prausnitz–Radke (P-R)) showed that Prausnitz–Radke model has the highest correlation coefficients with the smallest average relative error percentage. The maximum P-R adsorption capacity of HPAC decreased from 2.06 and 3.35 L/g in single pollutant solution to 1.02 and 1.51 L/g in binary pollutant solution at 298 K for Cs+ and Eu3+,respectively. The values of surface diffusion coefficient (DS) ranged within 10−8 for Cs+ and 10−8-10−9 cm2/s for Eu3+ in both studied single and binary pollutant systems. The external mass transfer coefficient (KF) was in the range of 10−4 for Cs+ and 10−3 cm/s for Eu3+ in both studied systems. Lastly, the Biot number (Bi) exposed that the diffusion inside the particle controlled the studied cations's adsorption onto HPAC material.

Interactions between micaceous minerals weathering and cesium adsorption

The environmental behavior of radioactive cesium (RCs) in contaminated areas is generally governed by soil and sediment components and natural weathering conditions. In this study, desorption tests and spectroscopic approaches were used to explore the interaction between the weathering of micaceous minerals (i.e., biotite and phlogopite) and the adsorption of Cs+ and the critical role of weathering in the environmental behavior of RCs. Results showed that the reaction sequence between weathering and Cs+ adsorption significantly affected the surface species of Cs+ and the structure of biotite and phlogopite. Regardless of whether it occurred before, after, or during Cs+ adsorption, weathering generated more high-affinity adsorption sites, namely, interlayer sites (ITs) and frayed edge sites (FESs), to different extents, and then facilitated the uptake of Cs+ at FESs and ITs on micaceous minerals in a poorly exchangeable state. Cs+ stabilized the micaceous mineral structure once it was absorbed within collapsed interlayers by hindering cation exchange and preventing further destruction during weathering. As important weathering factors, high temperature and Ca2+ content promoted the binding of Cs+ in the interlayers of biotite and phlogopite by enhancing interlayer cation exchange. These findings are beneficial for a better understanding of the environmental behaviors of RCs in the hydrosphere and pedosphere.

Tannic acid-assisted prussian blue anchoring on membranes for rapid and recyclable removal of cesium

As an effective adsorbent, prussian blue (PB) has been used to selectively eliminate radioactive cesium from the complex and change wastewater. Multiple attempts were introduced to refrain from the recovery difficulty of direct application of PB. This study designed a novel strategy of tannic acid (TA) assisted multilayer PB immobilization on a commercial substrate for cesium adsorption. As an effective binder, TA-Fe was successfully applied to immobilize and disperse PB to increase the number of active particles. The resulting composite membrane (MTA-PB) showed excellent cesium selectivity with a high Kd value of 8986 mL/g in geothermal water and maintained its cesium adsorption ability after 5 cycles. Compared with the reported PB powder, the loaded PB gave full play to the adsorption performance. The convenient fabrication method and effective removal of Cs from complex solutions demonstrated that the MTA-PB has excellent potential for practical application in low wastewater concentrations.

Comparative study of the cesium adsorption behavior of montmorillonite and illite based on their mineralogical properties and interlayer cations

Among clay minerals, montmorillonite (MMT) and illite are generally used to remove radioactive cesium (137Cs) from radioactive wastewater. The objectives of this study were to investigate the mineralogical properties of MMT and illite with their Cs adsorption behavior and then demonstrate the type of clay mineral that should be used for removing high- and low-concentrations of Cs. The Ca-type MMT used in this study was exchanged with sodium (Na), magnesium (Mg), and potassium (K) to compare the Cs adsorption behavior based on the interlayer cation type, including that of illite. The basal d-spacing (d001) of MMTs (swelling) ranged from 1.011 to 1.396 according to the interlayer cation type. Illite (non-swelling) had d001 of about 1.0 nm. Among the types, Na-MMT had the highest Cs adsorption capacity (204.67 mg/g), while illite exhibited the highest Cs distribution coefficient (Kd) (161.1 mL/g). The results indicated that the relative charge density of cations and interlayer properties, such as swelling and non-swelling, of clay minerals significantly affect Cs adsorption capacity and selectivity. Therefore, the selection of clay minerals should vary according to the type of high- and low-concentrated Cs wastewater. MMT and illite are advantageous for removing Cs from high- and low-concentration radioactive wastewater, respectively.

Systematic effect of different external metals of hexacyanoferrates on cesium adsorption behavior and mechanism

Systematic effect of different external metals of hexacyanoferrates on cesium adsorption behavior and mechanism

Self-propelling shuttles for radioactive caesium adsorption

Self-propelling shuttles for radioactive caesium adsorption.

Separation and Removal of Radionuclide Cesium from Water by Biodegradable Magnetic Prussian Blue Nanospheres

As the main component of radioactive wastewater, the cesium ion has seriously endangered the environment and human health. Prussian blue nanoparticles (PB NPs) are used as adsorbents for the purification of cesium-containing wastewater because of their ability to selectively adsorb cesium ions. In this work, novel magnetic Prussian blue nanospheres (MPBNs) were developed from polylactic acid nanospheres as a carrier, loaded with Fe3O4 nanoparticles (Fe3O4 NPs) inside and PB NPs outside for the removal of cesium ions with the help of magnetic separation. Meanwhile, the effects on the adsorption efficiency of MPBNs, such as pH, time, temperature and initial concentration of cesium ion solution, were studied. The adsorption isotherms, kinetic models and adsorption thermodynamics were investigated to research the absorption mechanism. The results showed that MPBNs were spherical with a rough surface, and their particle size, iron content and saturation magnetization were 268.2 ± 1.4 nm, 40.01% and 41.71 emu/g, which can be recovered by magnetic separation. At 293 K, MPBNs could reduce the cesium ion solution from 40 mg/L to 4.8 mg/L, and its cesium ion removal rate and adsorption capacity were 82.46% and 16.49 mg/g, respectively. The optimum pH of MPBNs for cesium ion adsorption was 5~9, the adsorption equilibrium time was 60 min, and the maximum adsorption capacity was 17.03 mg/g. In addition, MPBNs were separated rapidly by an external magnetic field, and the adsorption process was an endothermic reaction. The adsorption isotherm and kinetics of MPBNs were in accordance with the Freundlich model and quasi-second-order fitting model, respectively, and the adsorption process of MPBNs was controlled by the diffusion step in particles. Notably, these MPBNs could be effectively separated from water by a magnetic field, facilitating engineering applications in cesium-containing wastewater.