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1.
J Environ Radioact ; 270: 107287, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37677908

RESUMEN

A facile modification of a strontium-based MOF using oxalic acid was carried out to prepare MTSr-OX MOF, which was used as a potential substance for eliminating 152+154Eu radioisotopes. Various analytical techniques were used to characterize MTSr-OX-MOF. The prepared MOF had a rod-like structure with a BET surface area of 101.55 m2 g-1. Batch sorption experiments were used to investigate the sorption performance of MTSr-OX-MOF towards 152+154Eu radionuclides where different parameters like pH, contact time, initial 152+154Eu concentration, ionic strength, and temperature were scrutinized to determine the optimum conditions for 152+154Eu removal. MTSr-OX-MOF showed superior effectiveness in the elimination of 152+154Eu with a maximum sorption capacity of 234.72 mg g-1 at pH 3.5. Kinetics fitted with the pseudo-second-order model and the Langmuir model correctly described the sorption mechanism. The thermodynamic variables were carefully examined, demonstrating that the 152+154Eu sorption was endothermic as well as spontaneous. The MTSr-OX-MOF has been found to be a significantly more effective sorbent towards 152+154Eu than that of many other adsorbents. When applied to real active waste, MTSr-OX-MOF demonstrated excellent removal performance for a wide range of radionuclides. As a result, the MTSr-OX-MOF can be recognized as an attractive solution for the 152+154Eu purification from active waste.


Asunto(s)
Monitoreo de Radiación , Contaminantes Químicos del Agua , Estroncio/análisis , Adsorción , Radioisótopos , Termodinámica , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química
2.
RSC Adv ; 13(36): 25182-25208, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37622006

RESUMEN

The nuclear industry is rapidly developing and the effective management of nuclear waste and monitoring the nuclear fuel cycle are crucial. The presence of various radionuclides such as uranium (U), europium (Eu), technetium (Tc), iodine (I), thorium (Th), cesium (Cs), and strontium (Sr) in the environment is a major concern, and the development of materials with high adsorption capacity and selectivity is essential for their effective removal. Metal-organic frameworks (MOFs) have recently emerged as promising materials for removing radioactive elements from water resources due to their unique properties such as tunable pore size, high surface area, and chemical structure. This review provides an extensive analysis of the potential of MOFs as adsorbents for purifying various radionuclides rather than using different techniques such as precipitation, filtration, ion exchange, electrolysis, solvent extraction, and flotation. This review discusses various MOF fabrication methods, focusing on minimizing environmental impacts when using organic solvents and solvent-free methods, and covers the mechanism of MOF adsorption towards radionuclides, including macroscopic and microscopic views. It also examines the effectiveness of MOFs in removing radionuclides from wastewater, their behavior on exposure to high radiation, and their renewability and reusability. We conclude by emphasizing the need for further research to optimize the performance of MOFs and expand their use in real-world applications. Overall, this review provides valuable insights into the potential of MOFs as efficient and durable materials for removing radioactive elements from water resources, addressing a critical issue in the nuclear industry.

3.
Environ Geochem Health ; 45(6): 3345-3359, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36306038

RESUMEN

Water quality deterioration hinders economic and social development in developing countries that are facing freshwater security and shortages. Based on the collection of 29 water samples, this study focused on the relationship between sewage treatment plant and groundwater system surrounding it using multidisciplinary approach that combines the characterization of groundwater system and its connection with surrounding canal and drains, using chemical and isotopic characterization revealing that there is a direct relation between the surface water system and surrounding groundwater system. About 58% of the groundwater samples and all surface water samples in the investigated area are threatened by high concentrations of trace elements. The multivariate statistical analysis elucidates that anthropogenic effect and fertilizers sewage contamination are the main causes of groundwater pollution. Nearly, 31% and 11.5% of groundwater samples were posing oral chronic non-carcinogenic health risk and dermal chronic risk for adult, respectively, while all surface water samples were posing oral chronic non-carcinogenic health risk, with no dermal hazard. The uncharged species of Fe and Al are expected to be more mobile in groundwater because they would not be attracted to the surface charge of minerals. Inorganic ligands (HCO3-, SO42-, Cl-, and NO3-) act as nucleation centers that were linked with those trace elements creating new species with higher solubility degree in water that are transported away randomly for long distances in the water path.


Asunto(s)
Agua Subterránea , Oligoelementos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Aguas del Alcantarillado/análisis , Oligoelementos/análisis , Agua Subterránea/química , Calidad del Agua , Contaminantes Químicos del Agua/análisis
4.
RSC Adv ; 12(21): 13103-13110, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35497013

RESUMEN

Removal of hazardous radioactive materials such as 152+154Eu from active waste using the batch approach has attracted attention nowadays. In this work, a novel melamine-terephthalic strontium metal-organic framework (MTSr-MOF) was prepared via a hydrothermal method. The MTSr-MOF was characterized by various analytical techniques such as FT-IR, 1H/13C-NMR, mass spectroscopy, XPS, XRD, TGA, BET, FE-SEM/EDX, TEM, and UV. The obtained data revealed that MTSr-MOF exhibited brick-like building blocks that were bridged together by the linkers, and each block had a thickness of ∼120 nm. The BET surface area was 74.04 m2 g-1. MTSr-MOF was used for the removal of 152+154Eu radionuclides from active waste. Further functionalization using various modifiers, including oxalic acid, EDTA, sulfuric acid, and sodium hydroxide was carried out to improve the sorption efficiency of MTSr-MOF towards 152+154Eu radionuclides. Among them, MTSr-MOF modified with oxalic acid (MTSr-OX-MOF) demonstrated a superior removal efficiency toward 152+154Eu radionuclides when compared to MTSr-MOF or other published reports, with a removal efficiency of more than 96%. The higher sorption efficiency of the MTSr-OX-MOF indicates that it could be a promising candidate for the removal of 152+154Eu radionuclides from radioactive waste.

5.
Mater Sci Eng C Mater Biol Appl ; 76: 827-838, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28482597

RESUMEN

The fabrication of hydroxyapatite-Co-ferrite nanocomposite coatings was performed on stainless steel by chronoamperometry technique. HA-CoFe2O4 nanocomposite films were characterized using X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometer (VSM). The results reveal that CoFe2O4 nanoparticles dispersed within the HA matrix have flake and strip shapes. The magnetic property of the nanocomposite was increased by increasing the concentration of CoFe2O4 and a good saturation magnetization value was found to be 20.6emu/g with 50% CoFe2O4. By comparing with pure CoFe2O4, the composite still retain moderate magnetization as well as its biocompatible characters. The specific absorption rate (SAR) values were altered according to the change in CoFe2O4 concentration and the maximum SAR value was 125W/g. The incorporation of CoFe2O4 nanoparticles with HA coating was increased the corrosion resistance of HA in simulated body fluid (SBF). The results indicated that HA-CoFe2O4 nanocomposite coating could be a promising surface treatment technique for stainless steel medical implants as well hyperthermia treatment of cancer.


Asunto(s)
Nanocompuestos , Materiales Biocompatibles Revestidos , Cobalto , Durapatita , Técnicas Electroquímicas , Compuestos Férricos , Humanos , Neoplasias
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