A Study on the Applicability of NiFe2O4 Nanoparticles as the Basis of Catalysts for the Purification of Aqueous Media from Pollutants

Artem L. Kozlovskiy; Anna S. Zagrebova; Rauan Sh. Abdinov; Inesh E. Kenzhina; Maxim V. Zdorovets

doi:10.3390/catal11111393

A Study on the Applicability of NiFe2O4 Nanoparticles as the Basis of Catalysts for the Purification of Aqueous Media from Pollutants

Catalysts ◽

10.3390/catal11111393 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1393

Author(s):

Artem L. Kozlovskiy ◽

Anna S. Zagrebova ◽

Rauan Sh. Abdinov ◽

Inesh E. Kenzhina ◽

Maxim V. Zdorovets

Keyword(s):

Structural Changes ◽

Annealing Temperature ◽

Structural Parameters ◽

Sol Gel ◽

Aqueous Media ◽

Absorption Efficiency ◽

Subsequent Increase ◽

Temperature Range ◽

Nife2o4 Nanoparticles ◽

Agglomeration Of Nanoparticles

The aim of this work is to evaluate the application of NiFe2O4 nanoparticles with spinel structures as the basis of catalysts for the purification of aqueous media from pollutants such as manganese and arsenic. The interest in these catalysts is due to their ease of production and high absorption efficiency, which, together with their magnetic properties, allow the use of nanoparticles for a long time. The sol–gel method, followed by thermal annealing of the samples at different temperatures, was proposed as a method for the synthesis of spinel nanoparticles. The choice of the annealing temperature range of 200–1000 °C is caused by the possibility of estimating changes in the structural properties and the degree of nanoparticles crystallinity. During the study of structural changes in nanoparticles depending on the annealing temperature, it was found that in the temperature range of 200–800 °C, there is an ordering of structural parameters, while for samples obtained at annealing temperatures above 800 °C, there is a partial disorder caused by the agglomeration of nanoparticles with a subsequent increase in their size. According to the results of the studies on the purification of aqueous media from pollutants, it was found that the greatest absorption efficiency belongs to nanoparticles annealed at 500–700 °C, with the purification efficiency of 70–85%, depending on the type of pollutant. The results obtained from the use of nanoparticles as catalysts for the purification of aqueous media show great prospects for their further application on an industrial scale.

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Impact of annealing temperature on structural, optical and morphological properties of ZnO Nanoparticles Synthesized by a simple precipitation method

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681210666200316161346 ◽

2020 ◽

Vol 10 ◽

Author(s):

Lalita Deshmukh ◽

Kalyan Chavan

Keyword(s):

Zno Nanoparticles ◽

Annealing Temperature ◽

Zinc Acetate Dihydrate ◽

Aqueous Media ◽

Morphological Properties ◽

Precipitation Method ◽

Zinc Hydroxide ◽

Different Temperatures ◽

Excitonic Transition ◽

Agglomeration Of Nanoparticles

Objective: Herein, we report zinc oxide (ZnO) nanoparticles (NPs) synthesized by a simple precipitation method using zinc acetate dihydrate (Zn(CH3CO2)2. 2H2O) and sodium hydroxide (NaOH) precursors in aqueous media. Method: As synthesized material was annealed at different temperatures to check phase formation and its purity. Result: At room temperature sample shows the formation of zinc hydroxide and at high temperature (100, 200 & 300 oC) shows the formation of ZnO. Synthesized materials were analyzed by different techniques. X-ray diffraction analysis shows the formation of hexagonal crystal structure. Morphological features were analyzed by the SEM technique which shows agglomerated nanoparticles. Conclusion: The optical properties of ZnO were studied by using UV analysis and showed intrinsic excitonic transition property of the ZnO semiconductor. Further, with an increase in annealing temperature crystalline size, agglomeration of nanoparticles found to be increased whereas band gap decreases.

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Formation of a Co3O4 Top Layer in SiO2 Cobalt Containing Coatings Sol-gel Obtained

MRS Proceedings ◽

10.1557/proc-672-o8.31 ◽

2001 ◽

Vol 672 ◽

Author(s):

H. Tototzintle-Huitle ◽

A. Ramos-Mendoza ◽

A. Mendoza-Galván ◽

J. González-Hernández ◽

B. S. Chao

Keyword(s):

Cobalt Oxide ◽

Annealing Time ◽

Annealing Temperature ◽

Sol Gel ◽

Oxide Thickness ◽

X Ray ◽

Temperature Range ◽

Glass Substrates ◽

Diffusion Controlled ◽

Diffraction Patterns

ABSTRACTSiO2 coatings containing cobalt were prepared on glass substrates using the sol-gel method. It has been found that in coatings with a Si to Co ratio of 1.3, a layer of Co3O4 is formed at the free surface of the coating upon thermal annealings in air. The properties of the coatings were studied using optical, x-ray and Auger depth profile measurements. The thermal annealings in the temperature range of 300 to 500 oC, in steps of 50 oC, were performed for 10 min. Some samples were subjected to an isothermal annealing at 400 °C for different times from 10 to 210 min. From the x-ray diffraction patterns the cubic spinel structure of Co3O4 was detected after the thermal treatments. The optical reflection and transmission spectra for each annealing temperature and annealing time, are described with an air-Co3O4-SiO2:Co2+-substrate system. From this, the cobalt oxide thickness was obtained as a function of the annealing temperature and annealing time. From the Arrhenius plots, in the temperature range studied, it was found that the activation energy for the growth of the cobalt oxide layer is 0.41 eV. The layer thickness follows a parabolic behavior with time, which suggests a diffusion-controlled process. The Auger depth profiles obtained from a sample annealed at 500 °C confirm the optical model used.

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Effects of annealing temperature variation on the evolution of structural and magnetic properties of NiFe2O4 nanoparticles synthesized by starch-assisted sol–gel auto-combustion method

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2015.07.012 ◽

2015 ◽

Vol 394 ◽

pp. 439-447 ◽

Cited By ~ 37

Author(s):

Raghvendra Singh Yadav ◽

Jaromir Havlica ◽

Jiri Masilko ◽

Lukas Kalina ◽

Jaromir Wasserbauer ◽

...

Keyword(s):

Magnetic Properties ◽

Temperature Variation ◽

Annealing Temperature ◽

Sol Gel ◽

Combustion Method ◽

Auto Combustion ◽

Nife2o4 Nanoparticles ◽

Structural And Magnetic Properties

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A Transmission Electron Microscopical Investigation of Phase Transformations in TiNi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001446 ◽

1980 ◽

Vol 38 ◽

pp. 340-341

Author(s):

P. Moine ◽

G. M. Michal ◽

R. Sinclair

Keyword(s):

Electron Microscopy ◽

Phase Transformations ◽

Applied Stress ◽

Structural Changes ◽

Microscopical Investigation ◽

Temperature Range ◽

Transmission Electron ◽

Electron Microscopical ◽

Diffraction Effects ◽

Microscopy Images

Premartensitic effects in near equiatomic TiNi have been pointed out by several authors(1-5). These include anomalous contrast in electron microscopy images (mottling, striations, etc. ),diffraction effects(diffuse streaks, extra reflections, etc.), a resistivity peak above Ms (temperature at which a perceptible amount of martensite is formed without applied stress). However the structural changes occuring in this temperature range are not well understood. The purpose of this study is to clarify these phenomena.

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Quantitative relations between structure and antiinflammatory activity of aryloxoalkanoic acids

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19881862 ◽

1988 ◽

Vol 53 (8) ◽

pp. 1862-1872 ◽

Cited By ~ 11

Author(s):

Miroslav Kuchař ◽

Eva Maturová ◽

Bohumila Brunová ◽

Jaroslava Grimová ◽

Hana Tomková ◽

...

Keyword(s):

Regression Analysis ◽

Structural Changes ◽

Antiinflammatory Activity ◽

Structural Parameters ◽

Considerable Effect ◽

Antiinflammatory Effect ◽

Prolonged Action ◽

Preclinical Development ◽

Indicator Variables ◽

Inhibitory Activities

The antiinflammatory effect of a series of aryloxoalkanoic acids II and of their biphenyl derivatives III was examined by measuring the inhibition of the development of carageenan- and adjuvant-induced edemas. The quantitative relations between the antiinflammatory effect and physicochemical and structural parameters of the compounds tested were evaluated. The equations obtained by the method of regression analysis showed a significant linear dependence of both inhibitory activities on the lipophilicity of the compounds and a considerable effect of some structural changes as expressed by indicator variables. The antiinflammatory effect is especially enhanced in both tests by the presence of a cyclic substituent at the aromatic ring. The high antiinflammatory effect of biphenylyl derivatives III is paralleled by their prolonged action. The prolongation of the effect is most likely a result of a suitable biotransformation of acid III to an efficient metabolite. The structural requirements which resulted from both the regression analysis and from the hypothesis of biotransformation of acids III were utilized in the synthesis of suitably substituted biphenylyloxoalkanoic acids. By this approach derivatives IIIe-i were obtained some of which showed a high antiinflammatory and also protracted effect. 4-(2',4'-Difluorbiphenylyl)-4-oxo-2-methylbutanoic acid (VÚFB-16 066, Flobufen) was chosen for further preclinical development.

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Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.236 ◽

2012 ◽

Vol 501 ◽

pp. 236-241 ◽

Cited By ~ 1

Author(s):

Ftema W. Aldbea ◽

Noor Bahyah Ibrahim ◽

Mustafa Hj. Abdullah ◽

Ramadan E. Shaiboub

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Room Temperature ◽

Annealing Temperature ◽

Sol Gel ◽

Vibrating Sample Magnetometer ◽

X Ray ◽

Garnet Phase ◽

Sol Gel Process ◽

Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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Synthesis of novel adsorbent based on tetrasulfide-functionalized fibrous silica KCC-1 for removal of Hg(II) cations

Scientific Reports ◽

10.1038/s41598-021-90279-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Azam Marjani ◽

Reza Khan Mohammadi

Keyword(s):

Effective Interaction ◽

Sol Gel ◽

Aqueous Media ◽

Synthesis Method ◽

Mercury Ions ◽

Toxic Heavy Metals ◽

Uptake Capacity ◽

Hydrothermal Preparation ◽

Ultrasonic Assisted ◽

First Time

AbstractHg(II) has been identified to be one of the extremely toxic heavy metals because of its hazardous effects and this fact that it is even more hazardous to animals than other pollutants such as Ag, Au, Cd, Ni, Pb, Co, Cu, and Zn. Accordingly, for the first time, tetrasulfide-functionalized fibrous silica KCC-1 (TS-KCC-1) spheres were synthesized by a facile, conventional ultrasonic-assisted, sol–gel-hydrothermal preparation approach to adsorb Hg(II) from aqueous solution. Tetrasulfide groups (–S–S–S–S–) were chosen as binding sites due to the strong and effective interaction of mercury ions (Hg(II)) with sulfur atoms. Hg(II) uptake onto TS-KCC-1 in a batch system has been carried out. Isotherm and kinetic results showed a very agreed agreement with Langmuir and pseudo-first-order models, respectively, with a Langmuir maximum uptake capacity of 132.55 mg g–1 (volume of the solution = 20.0 mL; adsorbent dose = 5.0 mg; pH = 5.0; temperature: 198 K; contact time = 40 min; shaking speed = 180 rpm). TS-KCC-1was shown to be a promising functional nanoporous material for the uptake of Hg(II) cations from aqueous media. To the best of our knowledge, there has been no report on the uptake of toxic Hg(II) cations by tetrasulfide-functionalized KCC-1 prepared by a conventional ultrasonic-assisted sol–gel-hydrothermal synthesis method.

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Changes of Selected Structural and Mechanical Properties of the Strzelin Granites As Induced By Thermal Loads / Wpływ Obciążeń Termicznych Na Zmiany Niektórych Strukturalnych I Mechanicznych Właściwości Granitów Strzelińskich

Archives of Mining Sciences ◽

10.2478/v10267-012-0064-8 ◽

2012 ◽

Vol 57 (4) ◽

pp. 951-974 ◽

Cited By ~ 1

Author(s):

Andrzej Nowakowski ◽

Mariusz Młynarczuk

Keyword(s):

Mechanical Properties ◽

Nuclear Waste ◽

Structural Changes ◽

Structural Parameters ◽

Total Porosity ◽

Fracture Network ◽

Qualitative Description ◽

Temperature Changes ◽

Heating And Cooling ◽

Waste Repositories

Abstract Temperature is one of the basic factors influencing physical and structural properties of rocks. A quantitative and qualitative description of this influence becomes essential in underground construction and, in particular, in the construction of various underground storage facilities, including nuclear waste repositories. The present paper discusses the effects of temperature changes on selected mechanical and structural parameters of the Strzelin granites. Its authors focused on analyzing the changes of granite properties that accompany rapid temperature changes, for temperatures lower than 573ºC, which is the value at which the β - α phase transition in quartz occurs. Some of the criteria for selecting the temperature range were the results of measurements carried out at nuclear waste repositories. It was demonstrated that, as a result of the adopted procedure of heating and cooling of samples, the examined rock starts to reveal measurable structural changes, which, in turn, induces vital changes of its selected mechanical properties. In particular, it was shown that one of the quantities describing the structure of the rock - namely, the fracture network - grew significantly. As a consequence, vital changes could be observed in the following physical quantities characterizing the rock: primary wave velocity (vp), permeability coefficient (k), total porosity (n) and fracture porosity (η), limit of compressive strength (Rσ1) and the accompanying deformation (Rε1), Young’s modulus (E), and Poisson’s ratio (ν).

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Structural Changes of UHV Deposited Titanium Thin Films in Presence of Oxygen Flow and Temperature

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.1094 ◽

2011 ◽

Vol 110-116 ◽

pp. 1094-1098

Author(s):

Haleh Kangarlou ◽

Mehdi Bahrami Gharahasanloo ◽

Akbar Abdi Saray ◽

Reza Mohammadi Gharabagh

Keyword(s):

Room Temperature ◽

Structural Changes ◽

Annealing Temperature ◽

Annealing Process ◽

Oxygen Flow ◽

Glass Substrates ◽

Annealing Temperatures ◽

Titanium Thin Films ◽

Deposition Angle ◽

Ti Films

Ti films of same thickness, and near normal deposition angle, and same deposition rate were deposited on glass substrates, at room temperature, under UHV conditions. Different annealing temperatures as 393K, 493K and 593K with uniform 8 cm3/sec, oxygen flow, were used for producing titanium oxide layers. Their nanostructures were determined by AFM and XRD methods. Roughness of the films changed due to annealing process. The gettering property of Ti and annealing temperature can play an important role in the nanostructure of the films.

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