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Highly efficient separation of uranium from wastewater by in situ synthesized hydroxyapatite modified coal fly ash composite aerogel. J IND ENG CHEM 2022. [DOI: 10.1016/j.jiec.2022.11.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Hamza MF, Wei Y, Khalafalla MS, Abed NS, Fouda A, Elwakeel KZ, Guibal E, Hamad NA. U(VI) and Th(IV) recovery using silica beads functionalized with urea- or thiourea-based polymers - Application to ore leachate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 821:153184. [PMID: 35051487 DOI: 10.1016/j.scitotenv.2022.153184] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 12/15/2021] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Urea and thiourea have been successfully deposited at the surface of silica beads (through one-pot reaction with formaldehyde) for designing new sorbents for U(VI) and Th(IV) recovery (UR/SiO2 and TUR/SiO2 composites, respectively). These materials have been characterized by FTIR, titration, elemental analysis, BET, TGA, SEM-EDX for identification of structural and chemical properties, and interpretation of binding mechanisms. Based on deprotonation of reactive groups (amine, carbonyl, or thiocarbonyl) and metal speciation, the optimum pH was ~4. Uptake kinetics was fast (equilibrium within 60-90 min). Although the kinetic profiles are fitted by the pseudo-first order rate equation, the resistance to intraparticle diffusion cannot be neglected. Sorption isotherms were fitted by Langmuir equation (maximum sorption capacities: 1-1.2 mmol g-1). Thermodynamics are also investigated showing differences between the two types of functionalized groups: exothermic for TUR/SiO2 and endothermic for UR/SiO2. Metal desorption is highly effective using 0.3-0.5 M HCl solutions: total desorption occurs within 30-60 min; sorption/desorption properties are remarkably stable for at least 5 cycles. The sorbents have marked preference for U(VI) and Th(IV) over alkali-earth and base metals at pHeq ~4.8. By preliminary precipitation steps, it is possible "cleaning" ore leachates of pegmatite ore, and recovering U(VI) and Th(IV) using functionalized silica beads. After elution and selective recovery by precipitation with oxalate (Th-cake) and alkaline (U-cake), the metals can be valorized.
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Affiliation(s)
- Mohammed F Hamza
- School of Nuclear Science and Technology, University of South China, Heng Yang 421001, China; Nuclear Materials Authority, POB 530, El-Maadi, Cairo, Egypt.
| | - Yuezhou Wei
- School of Nuclear Science and Technology, University of South China, Heng Yang 421001, China; School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai, China.
| | | | - Neveen S Abed
- Nuclear Materials Authority, POB 530, El-Maadi, Cairo, Egypt.
| | - Amr Fouda
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University, Nasr City, Cairo 11884, Egypt.
| | - Khalid Z Elwakeel
- University of Jeddah, College of Science, Department of Chemistry, Jeddah, Saudi Arabia; Environmental Science Department, Faculty of Science, Port-Said University, Port-Said, Egypt.
| | - Eric Guibal
- Polymers Composites and Hybrids (PCH), IMT Mines Ales, Alès, France.
| | - Nora A Hamad
- Faculty of Science, Menoufia University, Shebine El-Koam, Egypt.
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Alharthi S. Separation of thorium(IV) from aquatic media using magnetic ferrite nanoparticles. RADIOCHIM ACTA 2021. [DOI: 10.1515/ract-2021-1075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Abstract
The separation and recovery of thorium from monazite is critical to the sustainable development of the nuclear industry as well as to environmental safety. Also, the removal of radionuclides from polluted sources is a critical issue in environmental control. Magnetic ferrite nanoparticles (MCMF-NP, Co0.5Mn0.5Fe2O4) were synthesized (4–22 nm in size) and characterized. MCMF-NP was investigated for Th(IV) separation from their aqueous medium under various test conditions of acidity, time, and Th(IV) concentration, in line with the uptake capacity. The amount of thorium adsorbed is improved when pH, time, and initial concentration are increased. The maximum uptake of Th(IV) by MCMF-NP was observed at pH 3.5–4 and a contact time of 180 min. A favorable adsorption mechanism was shown in the pseudo-second-order rate. Isotherm analysis shows an adequate process described by the Langmuir isotherm. MCMF-NP is an adsorbent capable of successful disposal of Th(IV) from waste solutions with a high uptake of 81.3 mg of Th(IV)/g of MCMF-NP. The possibility of re-using the MCMF-NP, adding value to this content as a way of compensating for the disposal costs, was studied and disused. MCMF-NP shows a good separation of thorium(IV) from monazite leach liquor as well as from wastewater samples.
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Affiliation(s)
- Sarah Alharthi
- Department of Chemistry , College of Science, Taif University , P.O. Box 11099 , Taif , 21944 , Saudi Arabia
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