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1.
Sci Rep ; 14(1): 19738, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39187526

RESUMO

Sorption of Sr(II) and Eu(III) from aqueous solutions was studied using tin molybdate talc sorbent synthesized by the precipitation technique. The synthesized sorbent was characterized using different analytical tools, such as; FT-IR, SEM, XRD, XRF, TGA, and DTA. The sorption studies applied to Sr(II) and Eu(III) include the effects of shaking time, pH, concentrations, and saturation capacity. The sorption of Sr(II) and Eu(III) depends on pH, reaction kinetics obey the pseudo-2nd-order model, and the Langmuir model is better suited for the sorption isotherm. The thermodynamic parameters reflect an endothermic and spontaneous sorption process. Desorption studies showed that 0.1 M HCl was the best desorbing agent for the complete recovery of Sr(II) (96.8%) and Eu(III) (92.9%). Finally, the obtained data illustrates that the synthesized sorbent can be applied and used as an efficient sorbent for the sorption of Sr(II) and Eu(III) from aqueous solutions and can be used as a promising sorbent to remove Sr(II) and Eu(III).

2.
Appl Radiat Isot ; 212: 111447, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39053040

RESUMO

A study was conducted to investigate the sorption of 85Sr from aqueous solutions using a fabricated magnesium molybdenum titanate (MgMoTi) composite. The MgMoTi composites were synthesized through the co-precipitation technique and characterized using different analytical tools, including FT-IR, XRD, SEM, and EDX. The sorption studies focused on 85Sr and examined factors such as shaking time, pH, ionic strength, temperature, initial ion concentration, and saturation capacity. The results obtained from the study indicated that, under optimum sorption conditions, the saturation capacity for 85Sr onto S-4 and S-5 was determined to be 23.31 and 37.72 mg g-1, respectively. The sorption of 85Sr exhibited dependence on pH and ionic strength. The kinetics of the sorption process followed the pseudo-2nd-order model, while the thermodynamics revealed an endothermic and spontaneous nature. Desorption studies revealed that 0.1 M HCl was the most effective eluent for the complete recovery of 85Sr. Furthermore, the recycling results demonstrated the excellent recyclability of MgMoTi, suggesting its potential application as a sorbent for the removal of 85Sr from aqueous solutions. Overall, the study highlights MgMoTi as a promising composite with practical utility in the sorption of 85Sr from aqueous solutions.

3.
Appl Radiat Isot ; 208: 111264, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38531244

RESUMO

The present study investigated the sorption behavior of 85Sr and 60Co radionuclides from aqueous solutions onto tin molybdate (SnMo) sorbent. SnMo has been synthesized using the precipitation method and was characterized using four analytical techniques including FT-IR, XRD, SEM, and XRF. The sorption studies applied on 85Sr and 60Co include the effect of shaking time, pH, concentration, and saturation capacity. The experimental data revealed that the sorption process was carried out after equilibrium time (180 min). The saturation capacity for 85Sr and 60Co is measured to be 58.1 and 52.2 mg g-1, respectively. The sorption behavior of studied radionuclides is dependent on pH values. Sorption kinetic better fit with the pseudo-second-order model. Furthermore, the sorption isotherm is better represented by the model proposed by Langmuir. The results of the desorption investigations indicated that the most effective eluents for achieving full recovery of investigated radionuclides were identified. Finally, the recycling results demonstrate the suitability of SnMo for affected sorbing of 85Sr and 60Co from aqueous solutions. All the obtained data clarify that the SnMo sorbent is an effective means of removing 85Sr and 60Co from liquid waste.

4.
Appl Radiat Isot ; 192: 110542, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36462302

RESUMO

Using a batch equilibrium technique, the sorption of 137Cs and 153Gd onto synthesized zirconium silico antimonate (ZrSiSb) sorbent was examined. The new sorbent was prepared by precipitation technique and characterized by diverse analytical tools. The influence of shaking time, pH, metal ion concentrations, temperature, and a real sample was carried out. The data indicate that ZrSiSb has a very fast equilibrium time (30 min). The distribution coefficient values as a function of pH have sequence order; Cs(I) > Gd(III). The reaction kinetic obeys the pseudo-2nd-order model. The saturation capacity is 69.8 and 27.2 mg/g for Cs(I) and Gd(III), respectively. Equilibrium data were analyzed by various sorption isotherm models. Desorption studies showed that the best eluents for complete recovery (about 99%) of the selected ions are KCl for Cs(I) and CaCl2 for Gd(III). The sorption effectiveness of the new ZrSiSb to remove 137Cs and 153Gd from real low-level radioactive waste was examined. The results obtained showed that the prepared new composite can be applied as a hoped sorbent material to get rid of these radionuclides from different wastewaters.


Assuntos
Gadolínio , Zircônio , Adsorção , Césio , Íons , Concentração de Íons de Hidrogênio , Cinética , Soluções
5.
Appl Radiat Isot ; 189: 110417, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36049444

RESUMO

This study is concerned with the sorption of 137Cs and/or 90Sr from low-level radioactive waste using tin(IV) vanadate (SnV) sorbent fabricated by the precipitation technique. The structure and properties of SnV were studied using different analytical tools such as X-ray diffraction, X-ray fluorescence, Fourier-transform infrared, and scanning electron microscopy. Batch technique was used to investigate the sorption behavior of SnV towards 137Cs and/or 90Sr considering the influence of independent parameters including pH of the solution, contact time, and initial metal ions concentrations in simulation studies using the γ emitting isotopes 134Cs and 85Sr as representatives of 137Cs and 90Sr, respectively. The sorption efficiency values of 70.3% and 92.2% were respectively obtained for 134Cs and 85Sr at optimum conditions (pH = 6, Ci = 100 mg/L, and time = 120 min). The amount sorbed (mg/g) increases by increasing pH and temperatures. The pseudo-2nd-order kinetic is a reaction command. Isotherm is more relevant to a Langmuir at different reaction temperatures. The sorption process was endothermic and spontaneous. The adsorption efficiency of the composite material was studied in removing both cesium and strontium nuclides from real low-level radioactive waste. This study showed that the new material can be used as a promising material to retain 137Cs and 90Sr from real radioactive waste.


Assuntos
Resíduos Radioativos , Adsorção , Césio/análise , Radioisótopos de Césio , Cinética , Resíduos Radioativos/análise , Estrôncio/química , Radioisótopos de Estrôncio , Estanho , Vanadatos
6.
Appl Radiat Isot ; 178: 109985, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34678639

RESUMO

129I and 79Se are potentially important anionic radionuclides in safety assessments due to their high mobility, radiotoxicity, and long half life's (1.7 × 107 and 3.27 × 105 years, respectively). This study is interested in the sorption of 131I and 75Se radionuclides onto magnesium iron hydrotalcite (Mg/Fe HTlc). Mg/Fe HTlc was prepared by co-precipitation technique and characterized using different analytical tools such as FT-IR, XRD, XRF, TGA & DTA, SEM, and BET. Results obtained from this study showed that the adsorption process was a very fast equilibrium time (20 min). The distribution coefficient values as a function of pH have high separation factors for 131I at all different pHs. Reaction kinetic obeys the pseudo-second-order model. Maximum sorption capacity for 131I and 75Se has the values 21.45, and 9.25 mg/g respectively. Sorption isotherms are more relevant to a Langmuir isotherm. The % removal of 131I is decreased by increasing the concentration of competing species. The investigation evidenced that the prepared sorbent is suitable for the removal of 131I and 75Se from radioactive waste and could be considered potential material for purification of effluent polluted with these radionuclides.

7.
Appl Radiat Isot ; 178: 109956, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34571457

RESUMO

Gamma-irradiation initiated polymerization was utilized to prepare polyacrylic acid dolomite P(AA/D) nanocomposites. Different analytical techniques have been applied to investigate the structure of the new materials. XRD and TEM revealed the crystalline phase with an average particle size ranging from 2 to 4 nm. The ability of the prepared materials to remove cesium, cobalt, and zirconium ions from aqueous solutions was evaluated. The adsorption capacity of studied nanocomposites has an affinity sequence; Zr4+>Co2+≫Cs+ with values 77.8, 72.4, and 34.9 mg/g respectively. The effect of the interfering species reveals that the rate of adsorption of cesium, cobalt, and zirconium ions decreases with increasing concentrations of the interfering species. The investigation proved that the prepared nanocomposite is suitable material for the removal of the studied metals from aqueous solutions and could be considered as potential material for purification of effluent polluted with these metal ions.

8.
Environ Geochem Health ; 43(8): 3169-3188, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33528682

RESUMO

Elimination of hazardous metals is of extreme worry for their toxicity at trace levels and accumulation in the biosystem. Polyacrylonitrile ball clay nanocomposite was prepared by gamma irradiation at 20 kGy. Different analytical tools were applied to prove morphology, functional groups, and chemical structure for prepared composite; SEM, TEM, IR, XRD, and XRF. From TEM and XRD data expose the studied composite has nanoscale and crystalline. The adsorption of Cs+, Co2+ and Fe3+ onto studied material took place after 24 h. Second order was preceded by the kinetic system. The capacity and effect of pH on kd reflect selectivity sequence; Co2+ > Fe3+ > > Cs+. Both Freundlich and Langmuir are applicable for investigated material. Finally, PAN/BC nanocomposite is suitable for the column technique.


Assuntos
Nanocompostos , Resinas Acrílicas , Adsorção , Argila , Raios gama , Cinética , Poluentes Químicos da Água/análise
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