New Chitosan/Iron Oxide Composites: Fabrication and Application for Removal of Sr2+ Radionuclide from Aqueous Solutions

Here, we discuss the fabrication and problems of application of chitosan-based composite materials for the removal of hazardous metal ions from tap water and wastewater. The chitosan-based composites containing iron oxides for the uptake of Sr2+ ions were fabricated via a co-precipitation method with variation of the iron/chitosan ratio and pH of the medium. The morphology and composition of the fabricated sorbents were characterized using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDX) and X-ray diffraction (XRD) analysis. We have shown that the suggested fabrication approach allows for a homogeneous distribution of the inorganic phase in the polymer matrix. Investigations of the sorption performance of the composites have shown that they are efficient sorbents for 90Sr radionuclides uptake from tap water. The composite sorbent containing amorphous iron oxide in a chitosan matrix and calcined at 105 °C showed the best sorption characteristics. We have also demonstrated that there is an optimal iron oxide content in the composite: with increasing oxide content, the efficiency of the sorbents decreases due to poor stability in solution, especially in alkaline media. The alternative approach yielding magnetic chitosan-based composites with sufficiently good sorption performance and stability in neutral and weakly alkaline media is suggested.

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Removal and Oxidation of As(III) from Water Using Iron Oxide Coated CTAB as Adsorbent

Polymers ◽

10.3390/polym12081687 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1687 ◽

Cited By ~ 2

Author(s):

Daniela Predoi ◽

Simona Liliana Iconaru ◽

Mihai Valentin Predoi ◽

Mikael Motelica-Heino

Keyword(s):

Iron Oxide ◽

Aqueous Solutions ◽

Photoelectron Spectroscopy ◽

Arsenic Removal ◽

Morphological Changes ◽

Xrd Analysis ◽

Precipitation Method ◽

Cubic Phase ◽

Separation Procedure ◽

X Ray

Iron oxides such as magnetite and maghemite coated with cetyltrimethylammonium bromide (CTAB) are very promising materials for wastewater treatment because iron oxide can be easily separated from solutions using the magnetic separation procedure Iron oxide (IO) coated CTAB was synthesized by an adapted co-precipitation method. In the present study, the IO-CTAB was used for removing arsenic from water for the first time. In the present study, the performance of iron oxide coated CTAB biocomposites as an adsorbent for arsenic removal from aqueous solutions was examined. X-ray diffraction (XRD) analysis and the results revealed a cubic phase Fd-3 m of Fe3O4 with lattice a = 8.40 Å and average crystal size equal to 17.26 ± 3 nm. The mean particle size calculated from transmission electron microscopy (TEM) was 19.86 ±1.7 nm. The results of the adsorption batch experiments and the data determined using the Langmuir and Freundlich models emphasized that IO-CTAB nanoparticles were favorable for the adsorption of As(III) ions from aqueous solutions. Ultrasound measurements have shown that IO-CTAB is a cost-effective biocomposite for removing arsenic from contaminated solutions. Moreover, x-ray photoelectron spectroscopy (XPS) has shown that during the process of arsenic absorption, there is oxidation from As(III) to As(V), which leads to a decrease in toxicity during this process. The results of the cytotoxic assays confirmed that the IO-CTAB nanoparticles did not induce any morphological changes in the HeLa cells and did not affect their proliferation after 24 h of incubation.

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Removal of Pb(II) and Cu(II) from aqueous solution using multiwalled carbon nanotubes/iron oxide magnetic composites

Water Science & Technology ◽

10.2166/wst.2011.270 ◽

2011 ◽

Vol 63 (5) ◽

pp. 917-923 ◽

Cited By ~ 46

Author(s):

Jun Hu ◽

Donglin Zhao ◽

Xiangke Wang

Keyword(s):

Carbon Nanotubes ◽

Iron Oxide ◽

Multiwalled Carbon Nanotubes ◽

Sorption Capacity ◽

Photoelectron Spectroscopy ◽

Metal Ion ◽

Precipitation Method ◽

Multiwalled Carbon ◽

Magnetic Composites ◽

X Ray

Multiwalled carbon nanotubes (MWCNTs)/iron oxide magnetic composites (named as MCs) were prepared by co-precipitation method, and were characterised by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) in detail. The prepared MCs were employed as an adsorbent for the removal of Pb(II) and Cu(II) ions from wastewater in heavy metal ion pollution cleanup. The results demonstrated that the sorption of Pb(II) and Cu(II) ions was strongly dependent on pH and temperature. The experimental data were well described by Langmuir model, and the monolayer sorption capacity of MCs was found to vary from 10.02 to 31.25 mg/g for Pb(II) and from 3.11 to 8.92 mg/g for Cu(II) at temperature increasing from 293.15 to 353.15 K at pH 5.50. The sorption capacity of Pb(II) on MCs was higher than that of Cu(II), which was attributed to their ionic radius, hydration energies and hydrolysis of their hydroxides. The thermodynamic parameters (i.e., ΔH0, ΔS0 and ΔG0) were calculated from temperature dependent sorption isotherms, and the results indicated that the sorption of Pb(II) and Cu(II) ions on MCs were spontaneous and endothermic processes.

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Synthesis, Structural Analysis of Cadmium Sulphide Nanocrystallites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.969.169 ◽

2019 ◽

Vol 969 ◽

pp. 169-174

Author(s):

R. Sivanand ◽

S. Chellammal ◽

S. Manivannan

Keyword(s):

Size Variation ◽

Cadmium Sulphide ◽

Xrd Analysis ◽

Sem Analysis ◽

Precipitation Method ◽

Capping Agent ◽

Energy Dispersive Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

In this paper, the effect of size variation of cadmium sulphide nanocrystallites which have been prepared by precipitation method is analyzed. These prepared samples were studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive analysis of spectroscopy (EDAX) techniques. SEM analysis represents the morphological nature of prepared samples and EDAX indicates the confirmation of elements present in the sample. XRD analysis determines the size of the samples and identifies the structure using miller indices (h k l values) of the nanocrystallies matches with JCPDS. From the XRD analysis, the size variation which depends on dopant, capping agent are discussed and corresponding results are reported in this paper.

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Iron oxide/titania composites for radar absorbing material (RAM) applications

Cerâmica ◽

10.1590/0366-69132019653752728 ◽

2019 ◽

Vol 65 (375) ◽

pp. 470-476 ◽

Cited By ~ 1

Author(s):

A. Fisli ◽

D. S. Winatapura ◽

E. Sukirman ◽

S. Mustofa ◽

W. A. Adi ◽

...

Keyword(s):

Iron Oxide ◽

Pore Volume ◽

Weight Ratio ◽

Total Pore Volume ◽

Precipitation Method ◽

Oxide Content ◽

Iron Oxide Content ◽

Radar Absorbing Material ◽

Radar Signature ◽

Absorbing Material

Abstract Iron oxide/titania composites were synthesized by precipitation method. Amount of iron oxide was varied in the composites. The single phase (anatase) was obtained for the weight ratio of 0-20% and three phases (anatase, magnetite and hematite) were found for the weight ratio of 30% and 40% of iron oxide. The crystallite size of titania decreased with increasing of iron oxide content. The specific surface area, total pore volume and BJH pore volume of the sample increased with increasing iron oxide content in the composite. The composites possessed mesoporous characteristic (6.5-9.6 nm in pore diameter) and exhibited ferromagnetic properties. The measurement of the microwave absorption showed that the 40Fe/Ti composite had the best reflection loss of -14 dB at a frequency of 10.9 GHz. This meant that the electromagnetic wave was absorbed 80% in that frequency. Thus, the developed material can be a promising microwave absorbing agent in radar signature reduction.

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Bio-assisted preparation of efficiently architectured nanostructures of γ-Fe2O3 as a molecular recognition platform for simultaneous detection of biomarkers

Scientific Reports ◽

10.1038/s41598-020-71934-7 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Sasikala Sundar ◽

V. Ganesh

Keyword(s):

Electron Microscopy ◽

Iron Oxide ◽

Photoelectron Spectroscopy ◽

Simultaneous Detection ◽

Differential Pulse ◽

Precipitation Method ◽

Limit Values ◽

X Ray ◽

Co Precipitation ◽

The Individual

Abstract Magnetic nanoparticles of iron oxide (γ-Fe2O3) have been prepared using bio-assisted method and their application in the field of biosensors is demonstrated. Particularly in this work, different nanostructures of γ-Fe2O3 namely nanospheres (NS), nanograsses (NG) and nanowires (NW) are prepared using a bio-surfactant namely Furostanol Saponin (FS) present in Fenugreek seeds extract through co-precipitation method by following “green” route. Three distinct morphologies of iron oxide nanostructures possessing the same crystal structure, magnetic properties, and varied size distribution are prepared and characterized. The resultant materials are analyzed using field emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, vibrating sample magnetometer and Fourier transform infrared spectroscopy. Moreover, the effect of reaction time and concentration of FS on the resultant morphologies of γ-Fe2O3 nanostructures are systematically investigated. Among different shapes, NWs and NSs of γ-Fe2O3 are found to exhibit better sensing behaviour for both the individual and simultaneous electrochemical detection of most popular biomarkers namely dopamine (DA) and uric acid (UA). Electrochemical studies reveal that γ-Fe2O3 NWs showed better sensing characteristics than γ-Fe2O3 NSs and NGs in terms of distinguishable voltammetric signals for DA and UA with enhanced oxidation current values. Differential pulse voltammetric studies exhibit linear dependence on DA and UA concentrations in the range of 0.15–75 µM and 5 μM – 0.15 mM respectively. The detection limit values for DA and UA are determined to be 150 nM and 5 µM. In addition γ-Fe2O3 NWs modified electrode showed higher sensitivity, reduced overpotential along with good selectivity towards the determination of DA and UA even in the presence of other common interferents. Thus the proposed biosensor electrode is very easy to fabricate, eco-friendly, cheaper and possesses higher surface area suggesting the unique structural patterns of γ-Fe2O3 nanostructures to be a promising candidate for electrochemical bio-sensing and biomedical applications.

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Evaluating the Extender Characteristics of Some Local Materials in Akure, Ondo State, Nigeria for Applications in the Paints Industry

MRS Advances ◽

10.1557/adv.2019.258 ◽

2019 ◽

Vol 4 (43) ◽

pp. 2355-2365

Author(s):

Ifeoma Janefrances Umunakwe ◽

Reginald Umunakwe ◽

Victor Adeola Popoola ◽

Uzoma Samuel Nwigwe ◽

Akinlabi Oyetunji

Keyword(s):

Refractive Index ◽

Specific Gravity ◽

Mesh Size ◽

Xrd Analysis ◽

Volatile Matter ◽

Oxide Content ◽

Oil Absorption ◽

X Ray Diffraction ◽

X Ray ◽

Ondo State

ABSTRACTSoil samples were obtained from three different locations; Ijapo, Ibule and FUTA North Gate in Akure, Ondo State, Nigeria. The materials were dried, crushed and calcined by heating the samples in a muffle furnace to 850 °C, holding for three hours and and then brought out of the furnace to cool in the laboratory so that the organic and volatile matter escaped, and the oxide content increased. The calcined materials were milled with a ball mill and then sieved with 75 µm mesh size British standard sieves. The samples that passed through the sieves were collected for analysis to determine their extender characteristics through x-ray flouresence (XRF) spectroscopy, x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), specific gravity, oil absorption, pH and refractive index measurements as well as the determination of their resistance to chemicals. XRF results showed that materials are kaolinite in nature. XRD results showed the phase compositions of each sample as materials suitable for applications as extenders in the paints industry. SEM micrographs showed the homogeneity of the samples from Ijapo and FUTA North Gate while the sample from Ibule showed segregation of the phase compositions. The specific gravity, pH, oil absorption and refractive index of each material were within the range of those of commercial extenders used in the paints industry. The calcined materials were found to be resistant to various chemical media. The characterized materials will be suitable as extenders and pigments in the paints industry.

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Effect of Concentration of Iron Oxide on Crystallization Behavior in Leadless Iron Oxide Crystalline Glaze

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.554-556.18 ◽

2012 ◽

Vol 554-556 ◽

pp. 18-22

Author(s):

Supakorn Silakate ◽

Anucha Wannagon ◽

Apinon Nuntiya

Keyword(s):

Iron Oxide ◽

Nepheline Syenite ◽

Crystallization Behavior ◽

Raw Materials ◽

Average Particle Size ◽

Average Particle ◽

Oxide Content ◽

Iron Oxide Content ◽

X Ray Diffraction ◽

X Ray

The objectives of this study were to prepare leadless crystalline glazes from iron oxide by using low temperature firing (1,100°C) and to study the effect of concentration of iron oxide on the phase composition of the glaze raw materials on phase transformation in leadless iron oxide crystalline glaze. The crystalline phases were investigated by using the DTA, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The composition of the glaze raw materials compose of nepheline syenite, colemanite, pottery stone, bentonite, ZnO, Li2CO3, SiOSubscript text2 and 10, 15 and 20%(w/w) iron oxide (Fe2O3). The glaze raw materials were ground for homogeneous mixtures by ball milling for 24h. The average particle size of the mixture was 3.86 µm. The glaze bodies were carried to firing at 1,100°C at the heating rate of 2°C/min and soaking for 0.5h. Then, the glaze bodies were cooled at the cooling rate of 1°C/min and maintained at 1,080°C for 3h and then maintained at 980°C for 1h, respectively. From the experiment results, it was found that the crystallization temperatures (Tc) of franklinite (ZnFe2O4) and anorthite (CaAl2Si2O8) depend on the concentration of iron oxide content.

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Toxicity Evaluation following Intratracheal Instillation of Iron Oxide in a Silica Matrix in Rats

BioMed Research International ◽

10.1155/2014/134260 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 8

Author(s):

Alina Mihaela Prodan ◽

Carmen Steluta Ciobanu ◽

Cristina Liana Popa ◽

Simona Liliana Iconaru ◽

Daniela Predoi

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Iron Oxide ◽

Intratracheal Instillation ◽

Xrd Analysis ◽

Silica Matrix ◽

Silica Xerogel ◽

Ferrous Chloride ◽

X Ray ◽

Chloride Hexahydrate

Iron oxide-silica nanoparticles (IOSi-NPs) were prepared from a mixture of ferrous chloride tetrahydrate and ferric chloride hexahydrate dropped into a silica xerogel composite. The structure and morphology of the synthesized maghemite nanoparticles into the silica xerogel were analysed by X-ray diffraction measurements, scanning electron microscopy equipped with an energy dispersive X-ray spectrometer, and transmission electron microscopy. The results of the EDAX analysis indicated that the embedded particles were iron oxide nanoparticles. The particle size of IOSi-NPs calculated from the XRD analysis was estimated at around 12.5 nm. The average size deduced from the particle size distribution is 13.7 ± 0.6 nm, which is in good agreement with XRD analysis. The biocompatibility of IOSi-NPs was assessed by cell viability and cytoskeleton analysis. Histopathology analysis was performed after 24 hours and 7 days, respectively, from the intratracheal instillation of a solution containing 0.5, 2.5, or 5 mg/kg IOSi-NPs. The pathological micrographs of lungs derived from rats collected after the intratracheal instillation with a solution containing 0.5 mg/kg and 2.5 mg/kg IOSi-NPs show that the lung has preserved the architecture of the control specimen with no significant differences. However, even at concentrations of 5 mg/kg, the effect of IOSi-NPS on the lungs was markedly reduced at 7 days posttreatment.

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The chromite deposits of the Fiskenæsset region, West Greenland

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v12.7160 ◽

1967 ◽

Vol 12 ◽

pp. 1-39

Author(s):

M Ghisler ◽

B.F Windley

Keyword(s):

Iron Oxide ◽

Total Iron ◽

Oxide Content ◽

Iron Oxide Content ◽

X Ray ◽

Average Value ◽

Maximum Thickness ◽

V2o5 Content ◽

Cr2o3 Content ◽

Almost All

The chromite deposits of the Fiskenæsset region occur in anorthosites, which together with intercalated pyribolites (hypersthene amphibolites) and subsidiary pyroxenites and peridotites occur in the gneisses as horizons belonging to a folded and metamorphosed stratiform complex which has a maximum thickness of 2 km. The chromite occurs in horizons which average 0.5 - 3 m in width, reaching a maximum of 20 m, and consist of alternating anorthosite and chromitite layers, usually between 0.5 and 10 cm wide. Chromite horizons occur in almost all of the anorthosite horizons in the region which have a minimum exposed length of 125 km. 175 X-ray fluorescence analyses show that the Cr2O3 content of the chromite varies between 26% and 36%, averaging 32.7%. The total iron oxide content varies between 28% and 42%, averaging 31. 8% (as FeO), with the result that the Cr:Fe ratio varies between 0.66 and 1.05, averaging 0.93. The chromite has a high V2O5 content varying from 0.2% to 0.5% with an average value of 0.3%. The chromite horizons occur along the shores of the fjords or only a few kilometres from the coast in easily accessible terrain that rarely exceeds 500 m in altitude. Fiskenæsset harbour is ice-free for the whole year.

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Synthesis and Characterization of Hydroxyapatite from Duck Eggshell by Wet Precipitation Process

Journal of Applied Materials and Technology ◽

10.31258/jamt.3.1.8-11 ◽

2021 ◽

Vol 3 (1) ◽

pp. 8-11

Author(s):

Yelmida Azis ◽

Cory Dian Alfarisi ◽

Komalasari Komalasari ◽

Khairat Khairat ◽

Yusnimar Sahan

Keyword(s):

Xrd Analysis ◽

Precipitation Method ◽

Molar Ratio ◽

Precipitation Process ◽

Stable Form ◽

X Ray Diffraction ◽

Precipitated Calcium Carbonate ◽

X Ray ◽

Inorganic Mineral

Hydroxyapatite (HAp, Ca10(PO4)6(OH)2) is the most stable form of calcium phosphate and widely used in various medical applications, mainly in orthopedics and dentistry due to its close similarities with the inorganic mineral component of bone and teeth. This study aims to synthesize hydroxyapatite from duck eggshell using the precipitation method. The duck eggshell was calcined, hydrated (slaking) and underwent carbonation to form Precipitated Calcium Carbonate (PCC). Afterwards, (NH4)2HPO4 was added to produce HAp by varying the molar ratio of Ca/P by 1.67, 1.77 and 1.87 and stirring speed by 200, 250, 300rpm under basic condition (pH 10 – 11). The best results were obtained at a molar ratio of 1.77 with 200rpm stirring speed. Furthermore, the X-ray Diffraction (XRD) analysis showed that its crystals were hexagonal with sizes of 23.062nm, in the absence of other crystalline phases. Therefore, the hydroxyapatite was obtained in the agglomerates form with a specific surface area of ??55.929m2/g.

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