Adsorption of H2S from Thermal Water Using Clinoptilolite

Abstract The goal was to study and develop the composite adsorbents to uptake H2S from thermal water on the base of natural zeolite clinoptilolite (CL) from deposit of Georgia and activated carbon (AC). Cation-modified forms of CL have been prepared by wet-milling method. The crystalline structure and content of prepared adsorbents have been studied by X-ray diffraction (XRD) technique, IR-and AAS methods. Adsorption experiments carried out varying the ratio zeolite: AC, composite: solution, duration of contact, granulation degree. The results obtained showed that modification of CL by ion-exchanging method with metal ions (Zn2+, Fe3+, Mn2, Cu2+) has improved the adsorption capacity. Adsorption equilibrium reached in seven-fifteen minutes, and adsorption activity grows in a row: DeCL < CL < CuDeCL < MnDeCL < FeDeCL < ZnDeCL < AC/CL. The sorption capacity ranged from 0.68 mg/g to 28.17 mg/g. pH of thermal water before sorption was 8.97 and in filtrates changed in very wide ranges – from 10.44 until 3.55 depending on type of modification. Presence of multivalent cations of metals in the zeolite confirmed to be an essential factor determined the adsorption activity in relation to H2S, adsorption occurs via both physical sorption and chemisorption. Most active was composite AC/CL with ratio AC:CL, equal 3:2. The difference for H2S between decationated and cation-exchanged forms of CL may be explained by the change of surface potential. Polarity of zeolites depends on Si/Al ratio, which by-turn depends on conditions of acid treatment.

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PENGARUH SUBSTITUSI ION Ti-Zn TERHADAP SIFAT KEMAGNETAN dan SIFAT PENYERAPAN GELOMBANG ELEKTROMAGNETIK MATERIAL SISTEM BaFe12-xTix/2Znx/2O19

SPEKTRA Jurnal Fisika dan Aplikasinya ◽

10.21009/spektra.022.02 ◽

2017 ◽

Vol 2 (2) ◽

pp. 99 ◽

Cited By ~ 1

Author(s):

Nenni Nenni ◽

Mutia Delina ◽

Wisnu Ari Adi ◽

Yana Taryana

Keyword(s):

Magnetic Material ◽

Electromagnetic Wave ◽

Reflection Loss ◽

Doping Concentration ◽

Hysteresis Curve ◽

Wet Milling ◽

X Ray Diffraction ◽

Electromagnetic Wave Absorption ◽

Wave Absorption ◽

Milling Method

Substitution of Ti+4 and Zn+2 ions on magnetic material BaFe12-xTix/2Znx/2O19 (x = 0 and 2) using the wet milling method has been performed. This research was conducted to get information the influence of Ti-Zn substitution on magnetic properties and its absorption. The magnetic material BaFe12-xTix/2Znx/2O19 is synthesized from a mixture of oxide materials, BaCO3, Fe2O3, TiO2 and ZnO. The mixture was milled for 5 hours, dried at 1000C then sintered at 10000C for 5 hours. The refinement result of the X-ray diffraction pattern shows that the sample has single phase BaFe12O19 with doping concentration of x = 0 and 2. The hysteresis curve shows that coercivity field value decreased in the sample with doping concentration of x = 2. The result of electromagnetic wave absorption shows that the substituted sample with Ti+4 and Zn+2 ions (doping concentration x = 2) has the highest absorption peak at a frequency of 11,2 GHz with reflection loss value (RL) of -24,3 dB. Electromagnetic wave absorption reaches 94% with sample thickness is about 1,0 mm. Therefore, the magnetic material BaFe12-xTix/2Znx/2O19 (x = 2) can be used for application of the electromagnetic wave absorber. Keywords: Substitution, BaFe12-xTix/2Znx/2O19, wet milling, reflection loss, electromagnetic wave absorber.

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Effect of Dispersants on Microstructures of Nano Alpha Alumina Developed from Aluminium Dross Waste

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1115.378 ◽

2015 ◽

Vol 1115 ◽

pp. 378-381 ◽

Cited By ~ 1

Author(s):

S. Anis Sofia ◽

Noorasikin Samat ◽

Meor Yusoff Meor Sulaiman

Keyword(s):

Particle Size ◽

Xrd Analysis ◽

Planetary Mill ◽

Wet Milling ◽

X Ray Diffraction ◽

Transmission Electron ◽

Particle Size Analyzer ◽

Milling Method ◽

Aluminium Dross ◽

Alpha Alumina

This paper compares the effect of dispersants which are Sodium Laureth Sulfate (SLS) and distilled water (DW) on the crystallization, particle size distribution and morphological behavior of nanoalpha Alumina (α-Al2O3) synthesized from Aluminium (Al) dross waste. The synthesizing of nanoα-Al2O3 via wet milling method was performed using a planetary mill for 4 hours at a speed of 550 rpm. The nanoα-Al2O3 powders with dispersants were characterized with x-ray diffraction (XRD), particle size analyzer (PSA) and transmission electron microscopy (TEM). XRD analysis shows the broadening and shifting of peaks after the sample was calcined at 1300 °C, indicating high crystallinity. The crystallite size of α-Al2O3 milled with SLS is also smaller than the α-Al2O3 milled with DW. These results are consistent with the PSA analysis in which the graphs displayed a symmetrical trend. Then, the PSA analysis is validated with TEM observation up to 100000x magnification, particularly for α-Al2O3 milled with SLS.

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Synthesis and Characterization of Calcium Oxide Nanoparticles from Duck Eggshells using Ball Milling Methods

Jurnal Kimia VALENSI ◽

10.15408/jkv.v5i2.8779 ◽

2019 ◽

Vol 5 (2) ◽

pp. 231-135

Author(s):

Ade Yeti Nuryantini ◽

Citra Deliana Dewi Sundari ◽

Halimahtussa’diah Halimahtussa’diah ◽

Bebeh Wahid Nuryadin

Keyword(s):

Ball Milling ◽

Calcium Oxide ◽

Particle Diameter ◽

Average Diameter ◽

Xrd Analysis ◽

Average Particle ◽

X Ray Diffraction ◽

Sem Images ◽

Milling Method ◽

The Difference

Calcium oxide (CaO) nanoparticles have been successfully synthesized from duck eggshells using ball milling method followed by simple calcination at 700°C for 7 hours. The observation on the morphology, size and shape of the particles of the eggshells powder was conducted through scanning electron microscope (SEM). The milling time was varied, i.e. 2, 6, 10, and 20 hours to observe the difference on the size of the produced particle. SEM images shows that the smallest average particle diameter was 520 nm, achieved by 20 hours of milling. When the particles were calcined, the average diameter was further reduced to 394 nm. The X-ray diffraction (XRD) analysis shows that the resulting particles contain calcium oxide, calcium hydroxide, and calcium carbonate.

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Antiphase Boundaries in Ordered Ni3FE Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006221x ◽

1969 ◽

Vol 27 ◽

pp. 62-63

Author(s):

Y. H. Liu

Keyword(s):

Domain Size ◽

Antiphase Domain ◽

X Ray Diffraction ◽

X Ray ◽

Hardening Mechanism ◽

Superlattice Structure ◽

Disordered Phase ◽

Domain Boundaries ◽

Atomic Scattering ◽

The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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Local atomic structure in tetragonal pure ZrO2nanopowders

Journal of Applied Crystallography ◽

10.1107/s0021889809054983 ◽

2010 ◽

Vol 43 (2) ◽

pp. 227-236 ◽

Cited By ~ 16

Author(s):

Leandro M. Acuña ◽

Diego G. Lamas ◽

Rodolfo O. Fuentes ◽

Ismael O. Fábregas ◽

Márcia C. A. Fantini ◽

...

Keyword(s):

Tetragonal Phase ◽

Local Structure ◽

X Ray Diffraction ◽

X Ray ◽

Atomic Structures ◽

Crystallite Sizes ◽

Exafs Study ◽

The Difference ◽

X Ray Absorption ◽

Good Agreement

The local atomic structures around the Zr atom of pure (undoped) ZrO2nanopowders with different average crystallite sizes, ranging from 7 to 40 nm, have been investigated. The nanopowders were synthesized by different wet-chemical routes, but all exhibit the high-temperature tetragonal phase stabilized at room temperature, as established by synchrotron radiation X-ray diffraction. The extended X-ray absorption fine structure (EXAFS) technique was applied to analyze the local structure around the Zr atoms. Several authors have studied this system using the EXAFS technique without obtaining a good agreement between crystallographic and EXAFS data. In this work, it is shown that the local structure of ZrO2nanopowders can be described by a model consisting of two oxygen subshells (4 + 4 atoms) with different Zr—O distances, in agreement with those independently determined by X-ray diffraction. However, the EXAFS study shows that the second oxygen subshell exhibits a Debye–Waller (DW) parameter much higher than that of the first oxygen subshell, a result that cannot be explained by the crystallographic model accepted for the tetragonal phase of zirconia-based materials. However, as proposed by other authors, the difference in the DW parameters between the two oxygen subshells around the Zr atoms can be explained by the existence of oxygen displacements perpendicular to thezdirection; these mainly affect the second oxygen subshell because of the directional character of the EXAFS DW parameter, in contradiction to the crystallographic value. It is also established that this model is similar to another model having three oxygen subshells, with a 4 + 2 + 2 distribution of atoms, with only one DW parameter for all oxygen subshells. Both models are in good agreement with the crystal structure determined by X-ray diffraction experiments.

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Problems Associated with Kα Doublet in Residual Stress Measurements

Advances in X-ray Analysis ◽

10.1154/s0376030800006492 ◽

1979 ◽

Vol 23 ◽

pp. 333-339

Author(s):

S. K. Gupta ◽

B. D. Cullity

Keyword(s):

Residual Stress ◽

Silicon Powder ◽

Lattice Parameter ◽

Diffraction Peak ◽

Parameter Determination ◽

X Ray Diffraction ◽

X Ray ◽

Analysis Techniques ◽

The Difference ◽

Similar Accuracy

Since the measurement of residual stress by X-ray diffraction techniques is dependent on the difference in angle of a diffraction peak maximum when the sample is examined consecutively with its surface at two different angles to the diffracting planes, it is important that these diffraction angles be obtained precisely, preferably with an accuracy of ± 0.01 deg. 2θ. Similar accuracy is desired in precise lattice parameter determination. In such measurements, it is imperative that the diffractometer be well-aligned. It is in the context of diffractometer alignment with the aid of a silicon powder standard free of residual stress that the diffraction peak analysis techniques described here have been developed, preparatory to residual stress determinations.

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Preparation of High Density Graphite Materials from Coal Tar Pitch

MRS Proceedings ◽

10.1557/proc-349-43 ◽

1994 ◽

Vol 349 ◽

Author(s):

Yang-Duk Park ◽

Chul-Woo Kim ◽

Young-Dae Seo

Keyword(s):

Mechanical Properties ◽

Coal Tar ◽

Resin Content ◽

High Density ◽

Coal Tar Pitch ◽

Wet Milling ◽

Density Graphite ◽

Milling Method

ABSTRACTPreparation of high density graphite materials from coal tar pitch was investigated. The effect of β-resin content on the mechanical properties of graphite solid prepared from semi-coke, which was prepared by wet milling method, was examined. β-Resin content was effective for fabrication of green bodies without lamination and for improving the mechanical properties of graphite materials.

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Relation between Magnetic, Spectroscopic and Structural Properties of Binuclear Copper(II) Complexes of Pentadentate Schiff-base Ligand, Semi-empirical and ab-initio Calculations

Zeitschrift für Naturforschung A ◽

10.1515/zna-2003-5-620 ◽

2003 ◽

Vol 58 (5-6) ◽

pp. 363-372 ◽

Cited By ~ 12

Author(s):

Y. Elerman ◽

H. Kara ◽

A. Elmali

Keyword(s):

Ab Initio ◽

Coupling Constants ◽

Antiferromagnetic Coupling ◽

X Ray Diffraction ◽

Hartree Fock ◽

Ligand Orbital ◽

Rhf Calculations ◽

The Difference ◽

Semi Empirical

The synthesis and characterization of [Cu2(L1)(3,5 prz)] (L1=1,3-Bis(2-hydroxy-3,5-chlorosalicylideneamino) propan-2-ol) 1 and of [Cu2(L2)(3,5 prz)] (L2=1,3-Bis(2-hydroxy-bromosalicylideneamino) propan-2-ol) 2 are reported. The compounds were studied by elemental analysis, infrared and electronic spectra. The structure of the Cu2(L1)(3,5 prz)] complex was determined by x-ray diffraction. The magnetochemical characteristics of these compounds were determined by temperaturedependent magnetic susceptibility measurements, revealing their antiferromagnetic coupling. The superexchange coupling constants are 210 cm−1 for 1 and 440 cm−1 for 2. The difference in the magnitude of the coupling constants was explained by the metal-ligand orbital overlaps and confirmed by ab-initio restricted Hartree-Fock (RHF) calculations. In order to determine the nature of the frontier orbitals, Extended Hückel Molecular Orbital (EHMO) calculations are also reported.

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Linear Structural Trends and Multi-Phase Intergrowths in Helvine-Group Minerals, (Zn,Fe,Mn)8[Be6Si6O24]S2

Minerals ◽

10.3390/min11030325 ◽

2021 ◽

Vol 11 (3) ◽

pp. 325

Author(s):

Sytle Antao

Keyword(s):

Cell Parameter ◽

Structural Parameters ◽

Unit Cell ◽

Fluid Composition ◽

Ternary Solid Solution ◽

X Ray Diffraction ◽

X Ray ◽

The Difference ◽

Multi Phase ◽

And Diffusion

Synchrotron high-resolution powder X-ray diffraction (HRPXRD) and Rietveld structure refinements were used to examine the crystal structure of single phases and intergrowths (either two or three phases) in 13 samples of the helvine-group minerals, (Zn,Fe,Mn)8[Be6Si6O24]S2. The helvine structure was refined in the cubic space group P4¯3n. For the intergrowths, simultaneous refinements were carried out for each phase. The structural parameters for each phase in an intergrowth are only slightly different from each other. Each phase in an intergrowth has well-defined unit-cell and structural parameters that are significantly different from the three endmembers and these do not represent exsolution or immiscibility gaps in the ternary solid-solution series. The reason for the intergrowths in the helvine-group minerals is not clear considering the similar radii, identical charge, and diffusion among the interstitial M cations (Zn2+, Fe2+, and Mn2+) that are characteristic of elongated tetrahedral coordination. The difference between the radii of Zn2+ and Mn2+ cations is 10%. Depending on the availability of the M cations, intergrowths may occur as the temperature, pressure, fugacity fS2, and fluid composition change on crystallization. The Be–Si atoms are fully ordered. The Be–O and Si–O distances are nearly constant. Several structural parameters (Be–O–Si bridging angle, M–O, M–S, average <M–O/S>[4] distances, and TO4 rotational angles) vary linearly with the a unit-cell parameter across the series because of the size of the M cation.

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Atomic structure and phason modes of the Sc–Zn icosahedral quasicrystal

IUCrJ ◽

10.1107/s2052252516007041 ◽

2016 ◽

Vol 3 (4) ◽

pp. 247-258 ◽

Cited By ~ 11

Author(s):

Tsunetomo Yamada ◽

Hiroyuki Takakura ◽

Holger Euchner ◽

Cesar Pay Gómez ◽

Alexei Bosak ◽

...

Keyword(s):

Atomic Structure ◽

Diffuse Scattering ◽

Waller Factor ◽

Close Packing ◽

Icosahedral Quasicrystal ◽

X Ray Diffraction ◽

X Ray ◽

Large Atom ◽

Debye Waller Factor ◽

The Difference

The detailed atomic structure of the binary icosahedral (i) ScZn7.33quasicrystal has been investigated by means of high-resolution synchrotron single-crystal X-ray diffraction and absolute scale measurements of diffuse scattering. The average atomic structure has been solved using the measured Bragg intensity data based on a six-dimensional model that is isostructural to the i-YbCd5.7one. The structure is described with a quasiperiodic packing of large Tsai-type rhombic triacontahedron clusters and double Friauf polyhedra (DFP), both resulting from a close-packing of a large (Sc) and a small (Zn) atom. The difference in chemical composition between i-ScZn7.33and i-YbCd5.7was found to lie in the icosahedron shell and the DFP where in i-ScZn7.33chemical disorder occurs on the large atom sites, which induces a significant distortion to the structure units. The intensity in reciprocal space displays a substantial amount of diffuse scattering with anisotropic distribution, located around the strong Bragg peaks, that can be fully interpreted as resulting from phason fluctuations, with a ratio of the phason elastic constantsK2/K1= −0.53,i.e.close to a threefold instability limit. This induces a relatively large perpendicular (or phason) Debye–Waller factor, which explains the vanishing of `high-Qperp' reflections.

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