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Utilization of synthetic nano-cryptomelane for enhanced scavenging of cesium and cobalt ions from single and binary solutions. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08231-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractThe feasibility of using nano-cryptomelane for elimination of cobalt and cesium metal ions from their single and binary solutions was studied. In this respect, the material was prepared and characterized to confirm its chemical composition and structure. Results illustrate that the synthesized nano-cryptomelane has a tunnel structure with particle size ranged between 4 and 6 nm. The material feasibility was detected by conducting a series of batch experiments for determination of the kinetic and equilibrium performance of the removal process. All characteristic Raman bands for Mn–O lattice vibrations within the (2 × 2) tunnel structure of MnO6 octahedral are observed which confirm formation of nano-cryptomelane. The specific surface area (SSA) for nano-cryptomelane was calculated and equal to 299.03 m2/g while the surface fractal information (Ds) was2.53. The process sensitivity to changes of H+ concentration is attributed to changes in structural elements-species distribution at the solid/aqueous interface. The pH optimum value was desired at pH 5 for exchange of Cs+ and/or Co2+ with K+ ions. The equilibrium studies show that Langmuir isotherm model was more fitted to the experimental data than that of Freundlich model.
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Soot Combustion over Niobium-Doped Cryptomelane (K-OMS-2) Nanorods—Redox State of Manganese and the Lattice Strain Control the Catalysts Performance. Catalysts 2020. [DOI: 10.3390/catal10121390] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A series of Nb-doped (0–23 wt%) cryptomelane catalyst (Nb-K-OMS-2) was synthesized and thoroughly characterized by XRD, TEM/EDX, XRF, XPS, XAS, UV-Vis, and Raman techniques corroborated by the work function measurements. The obtained catalysts were tested for soot oxidation (Printex U) in model tight and loose contact modes. It was shown that the catalytic properties of the Nb-K-OMS-2 are controlled by the amount of Nb dopant in a strongly non-monotonous way. The introduction of niobium gives rise to the strain in the cryptomelane lattice, accompanied by significant Mn+3/Mn+4 ratio variations and concomitant work function changes. The isotopic exchange experiments revealed that the catalytic activity of the Nb-OMS-2 catalysts in soot combustion proceeds via the pathways, where both the activated suprafacial 18O and the surface 16O2− species participate together in the reaction. The niobium doping level controls the non-monotonous changes of the catalyst work function and the lattice strain, and variations of these parameters correlate well with the observed deSoot activity. To our best knowledge, the role of the lattice strain of the cryptomelane catalysts was documented for the first time in this study.
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Ghaly M, El-Sherief EA, Metwally SS, Saad EA. Utilization of nano-cryptomelane for the removal of cobalt, cesium and lead ions from multicomponent system: Kinetic and equilibrium studies. JOURNAL OF HAZARDOUS MATERIALS 2018; 352:1-16. [PMID: 29567406 DOI: 10.1016/j.jhazmat.2018.03.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 03/10/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
Nano-cryptomelane was prepared and characterized using SEM with mapping, HRTEM, FT-IR spectra, thermal analysis and surface area. The diameter distribution of nano-cryptomelane was found to be 4-6 nm. Sorption performance of the prepared material was studied for the removal of Co2+, Cs+ and Pb2+ from a multi-system solution of equal molar ratio, 1:1:1. The sorption capacity of nano-cryptomelane was found to be 179.6, 442.6 and 716.9 mg/g for Co2+, Cs+ and Pb2+, respectively. The kinetic studies revealed that the sorption process obeys non-linear pseudo-second-order model and is controlled by an intra-particle diffusion mechanism. The equilibrium isotherm investigations outlined that the extended Langmuir isotherm model fits the data reasonably well and it is more applicable than Freundlich multicomponent sorption isotherm. The value of diffusion coefficient for the three metal ions is in the order 10-17 m2/s which indicates the chemisorption nature of the process. The desorption percentage attains the maximum value (98.13%, 97.29 and 97.04 for lead, cesium and cobalt ions, respectively) using 0.7 mol/L of HNO3. This revealed that nano-cryptomelane can be regenerated and reused for farther sorption of Pb2+, Cs+ and Co2+ from wastewater.
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Affiliation(s)
- M Ghaly
- Hot Laboratories Center, Atomic Energy Authority, Post Code 13759, Cairo, Egypt
| | - E A El-Sherief
- Hot Laboratories Center, Atomic Energy Authority, Post Code 13759, Cairo, Egypt
| | - S S Metwally
- Hot Laboratories Center, Atomic Energy Authority, Post Code 13759, Cairo, Egypt.
| | - E A Saad
- Department of Chemistry, Faculty of Science, Ain Shams University, Cairo, Egypt
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Li W, Zhu Z, Shen W, Tang J, Yang G, Xu Z. A novel PVdF-based composite gel polymer electrolyte doped with ionomer modified graphene oxide. RSC Adv 2016. [DOI: 10.1039/c6ra16618k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel composite gel polymer electrolyte (CGPE) was prepared by doping ionomer-modified-graphene (IMGO) into poly(vinylidenefluoride) with a phase separation technique. IMGO can enhance the properties of CGPE due to the effect of the ion-conducting channel.
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Affiliation(s)
- Weili Li
- School of Material Science and Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- China
- Suzhou Jiren Hi-Tech Material Co., Ltd
| | - Zhengbao Zhu
- School of Material Science and Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- China
| | - Wenjun Shen
- School of Material Science and Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- China
| | - Jijun Tang
- School of Material Science and Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- China
| | - Gang Yang
- School of Material Science and Engineering
- Jiangsu University of Science and Technology
- Zhenjiang 212003
- China
- Jiangsu Laboratory of Advanced Functional Material
| | - Zexiao Xu
- Suzhou Jiren Hi-Tech Material Co., Ltd
- Suzhou 215143
- China
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Sun J, Yang N, Sun Z, Zeng M, Fu L, Hu C, Hu S. Fully Converting Graphite into Graphene Oxide Hydrogels by Preoxidation with Impure Manganese Dioxide. ACS APPLIED MATERIALS & INTERFACES 2015; 7:21356-63. [PMID: 26352992 DOI: 10.1021/acsami.5b06008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Potassium permanganate (KMnO4) has been proved to be an efficient oxidant for converting graphite into graphite oxide, but its slow diffusion in the interlayer of graphite seriously restricts the production of graphene oxide (GO). Here, we demonstrate that the preoxidation of graphite by impure manganese dioxide (MnO2) in a mixture of concentrated sulfuric acid (H2SO4) and phosphorus pentoxide (P2O5) can efficiently improve the synthesis of GO when KMnO4 is employed as the oxidant. The prepared honey-like GO hydrogels possess a high yield of single-layer sheets, large sizes (average lateral size up to 20 μm), wide ranges of stable dispersion concentrations (from dilute solutions, viscous hydrogels, to dry films), and good conductivity after reduction (~2.9 × 10(4) S/m). The mechanism for the improved synthesis of GO by impure MnO2 was explored. The enhanced exfoliation and oxidation of graphite by oxidative Mn ions (mainly Mn(3+)), which are synergistically produced by the reaction of impure MnO2 with H2SO4 and P2O5, are found to be responsible for the improved synthesis of such GO hydrogels. Particularly, preoxidized graphite (POG) can be partially dispersed in water with sonication, which allows the facile construction of flexible and highly conductive graphene nanosheet film electrodes with excellent electrochemical sensing properties.
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Affiliation(s)
- Jiaojiao Sun
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
| | - Ningxin Yang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
| | - Zhe Sun
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
| | - Mengqi Zeng
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
| | - Lei Fu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
| | - Chengguo Hu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
| | - Shengshui Hu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University , Wuhan 430072, China
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Xu W, Deng Z, Li G. Facile Preparation of Nanocryptomelane and Its Application in the Treatment of Aqueous Solutions Containing Basic Fuchsin. Ind Eng Chem Res 2012. [DOI: 10.1021/ie302202r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wei Xu
- State
Key Laboratory of Pollution Control and Resources Reuse, College of
Environmental Science and Engineering, and ‡Department of Chemistry, Tongji University, 1239 Siping Road,
Shanghai 200092, China
| | - Zifeng Deng
- State
Key Laboratory of Pollution Control and Resources Reuse, College of
Environmental Science and Engineering, and ‡Department of Chemistry, Tongji University, 1239 Siping Road,
Shanghai 200092, China
| | - Guangming Li
- State
Key Laboratory of Pollution Control and Resources Reuse, College of
Environmental Science and Engineering, and ‡Department of Chemistry, Tongji University, 1239 Siping Road,
Shanghai 200092, China
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Synthesis and catalytic activity of manganese dioxide (type OMS-2) for the abatement of oxygenated VOCs. Catal Today 2008. [DOI: 10.1016/j.cattod.2007.12.132] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lemus MA, López T, Recillas S, Frías D, Montes M, Delgado J, Centeno M, Odriozola J. Photocatalytic degradation of 2,4-dichlorophenoxyacetic acid using nanocrystalline cryptomelane composite catalysts. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.molcata.2007.10.037] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Cheney MA, Bhowmik PK, Moriuchi S, Birkner NR, Hodge VF, Elkouz SE. Synthesis and characterization of two phases of manganese oxide from decomposition of permanganate in concentrated sulfuric acid at ambient temperature. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2007.05.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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