Determination of mercury content in hard coal and fly ash using X-ray diffraction and scanning electron microscopy coupled with chemical analysis

AbstractTrachyandesite rocks, occurring over an area of about 1 km2in the southwest part of Limnos Island, Greece, are altered mainly to halloysite. The samples were collected and analysed by polarizing microscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and chemical analysis. The alteration of plagioclase to halloysite follows seven discrete stages that are described in detail. The geochemical evaluation of the data shows enrichment of the lightREE(LREE) over heavyREE(HREE) as expressed by the (La/Yb)n ratio. TheΣLREErange from 206.44 to 272.30, while the sum ofHREEvaries from 11.01 to 26.26. The (La/Yb)n ratio ranges from 9.72 to 27.64. Fractionation amongLREEexpressed as (La/Sm)n and between middleREE(MREE) andHREEis shown as (Tb/Yb)n ratios. The most altered rocks close to the fault zone have high (Tb/Yb)n ratios and low (La/Sm)n and Eu/Eu* ratios. Although mineralogy and clay mineral textures indicate hydrothermal genesis of halloysite, the geochemical data are not conclusive due to a secondary weathering effect.

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Influence of Fly Ash on Corrosion Resistance of Refractory Forsterite-Spinel Ceramics

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.325.181 ◽

2021 ◽

Vol 325 ◽

pp. 181-187

Author(s):

Martin Nguyen ◽

Radomír Sokolář

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Corrosion Resistance ◽

Fly Ash ◽

Raw Materials ◽

X Ray Diffraction ◽

X Ray ◽

Transition Zones ◽

Refractory Ceramics ◽

Scanning Electron

This article examines the influence of fly ash on corrosion resistance of refractory forsterite-spinel ceramics by molten iron as a corrosive medium. Fly ash in comparison with alumina were used as raw materials and sources of aluminium oxide for synthesis of forsterite-spinel refractory ceramics. Raw materials were milled, mixed in different ratios into two sets of mixtures and sintered at 1550°C for 2 hours. Samples were characterized by X-ray diffraction analysis and thermal dilatometric analysis. Crucibles were then made from the fired ceramic mixtures and fired together with iron at its melting point of 1535°C for 5 hours. The corrosion resistance was evaluated by scanning electron microscopy on the transition zones between iron and ceramics. Mixtures with increased amount of spinel had higher corrosion resistance and mixtures with fly ash were comparable to mixtures with alumina in terms of corrosion resistance and refractory properties.

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UTILIZATION OF FLY ASH AND CONCRETE RESIDUE IN THE PRODUCTION OF GEOPOLYMER BRICKS

Journal of Green Building ◽

10.3992/1552-6100.12.1.63 ◽

2017 ◽

Vol 12 (1) ◽

pp. 63-77 ◽

Cited By ~ 1

Author(s):

Siriporn Sirikingkaew ◽

Nuta Supakata

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Compressive Strength ◽

Phase Composition ◽

Fly Ash ◽

Industrial Waste ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

This study presents the development of geopolymer bricks synthetized from industrial waste, including fly ash mixed with concrete residue containing aluminosilicate compound. The above two ingredients are mixed according to five ratios: 100:0, 95:5, 90:10, 85:15, and 80:20. The mixture's physico-mechanical properties, in terms of water absorption and the compressive strength of the geopolymer bricks, are investigated according to the TIS 168-2546 standard. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses are used to investigate the microstructure and the elemental and phase composition of the brick specimens. The results indicate that the combination of fly ash and concrete residue represents a suitable approach to brick production, as required by the TIS 168–2546 standard.

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Analyse des Stuckgipses der Abtei Villers / Analysis of Stucco from the Abbey of Villers

Restoration of Buildings and Monuments ◽

10.1515/rbm-1997-5196 ◽

1997 ◽

Vol 3 (4) ◽

pp. 381-396

Author(s):

S. Chandra ◽

D. Van Gemert

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Chemical Analysis ◽

Electron Spectroscopy ◽

Natural Polymer ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Abstract Interior plaster from the Abbot's Palace of the Abbey of Villers-la-Ville, Brabant Wallon province, Belgium has been investigated. It is done by using chemical analysis, x-ray diffraction analysis, scanning electron microscopy, energy dispersive electron spectroscopy, and transmission electron microscopy. It is found that the rendering was made with lime rich mortar and animal hairs. The sand used was very fine and the hairs were very short. The solid constituents and the hairs were uniformly dispersed, which could have been obtained by the addition of some other natural polymer, containing protein.

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Quantitative Evaluation of Crystalline and Amorphous Phases in Clay-Based Cordierite Ceramic

Minerals ◽

10.3390/min10121122 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1122

Author(s):

Zdeněk Klika ◽

Marta Valášková ◽

Lucie Bartoňová ◽

Petra Maierová

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Chemical Analysis ◽

Test Results ◽

Mineral Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Amorphous Phases ◽

Cordierite Ceramic ◽

Scanning Electron

An innovative chemical quantitative mineral analysis (CQMA) was successfully tested on a cordierite-based clay ceramic sample to quantify crystalline and amorphous components. The accuracy of this method was demonstrated on an added module to the CQMA program that used oxide formulas of amorphous phases obtained by energy dispersive X-ray spectroscopy (EDS) microprobe chemical analysis. This CQMA method was tested for three variants calculated using chemical analysis, i.e., X-ray diffraction (XRD) identification of crystalline (cordierite and enstatite) and amorphous phases by scanning electron microscopy (SEM)/EDS texture and microanalyses. The test results from CQMA suggest their application possibilities as well as the limits of their utilization.

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Study of an Energetic-oxidant Co-crystal: Preparation, Characterisation, and Crystallisation Mechanism

Defence Science Journal ◽

10.14429/dsj.67.10188 ◽

2017 ◽

Vol 67 (5) ◽

pp. 510 ◽

Cited By ~ 1

Author(s):

Han Gao ◽

Wei Jiang ◽

Jie Liu ◽

Gazi Hao ◽

Lei Xiao ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Differential Scanning Calorimetry ◽

Diffraction Spectrum ◽

Solvent Evaporation Method ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Scanning Electron

<p>An energetic co-crystal consisting of the most promising military explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and the most well-known oxidant applied in propellants ammonium perchlorate has been prepared with a simple solvent evaporation method. Scanning electron microscopy revealed that the morphology of co-crystal differs greatly from each component. The X-ray diffraction spectrum, FTIR, Raman spectra, and differential scanning calorimetry characterisation further prove the formation of the co-crystal. The result of determination of hygroscopic rate indicated the hygroscopicity was effectively reduced. At last, the crystallisation mechanism has been discussed.</p>

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Stability of Cs-Ionsiv in Portland cement blends for radioactive waste disposal

MRS Proceedings ◽

10.1557/proc-1265-aa06-06 ◽

2010 ◽

Vol 1265 ◽

Author(s):

Neil Christian Hyatt ◽

Andreas Jenni ◽

Martin Christopher Stennett

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fly Ash ◽

Radioactive Waste ◽

Portland Cement ◽

Radioactive Waste Disposal ◽

X Ray Diffraction ◽

X Ray ◽

Leaching Experiments ◽

Scanning Electron

AbstractThe suitability of Portland cement blends for encapsulation of Cs-Ionsiv in a monolithic wasteform was investigated. No evidence of reaction or dissolution of the Cs-Ionsiv in the cementitious environment was found by scanning electron microscopy and X-ray diffraction. However, a small fraction (≤1.6 wt%) of the Cs inventory was released from the encapsulated Ionsiv during leaching experiments carried out on hydrated samples. Cs release was enhanced by exchange of K and Na present in the cementitious pore water. Cement systems lower in K and Na, such as slag based blends, showed lower Cs release than the fly ash based analogues.

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Coal Combustion Fly Ash Characterization: Electron Spectroscopy for Chemical Analysis, Energy Dispersive X-ray Analysis, and Scanning Electron Microscopy

Applied Spectroscopy ◽

10.1366/0003702804731230 ◽

1980 ◽

Vol 34 (5) ◽

pp. 549-555 ◽

Cited By ~ 25

Author(s):

S. J. Rothenberg ◽

P. Denee ◽

P. Holloway

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fly Ash ◽

Chemical Analysis ◽

Electron Spectroscopy ◽

Energy Dispersive ◽

Compositional Variation ◽

X Ray ◽

Calcium Iron ◽

Scanning Electron

The surface and bulk properties of five samples of fly ash have been examined by electron spectroscopy for chemical analysis (ESCA), scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDXA). Samples from a conventional pulverized coal combustor, a conventional stoker-fed combustor, and an experimental fluidized bed combustor (FBC) were examined. ESCA data indicated that all samples contained silicon, aluminum, magnesium, calcium, iron, potassium, carbon, oxygen, and sulfur and all but one contained titanium. Samples from the conventional combustors contained more carbon than samples from the FBC. FBC samples contained large amounts of calcium and magnesium. Valence states of some elements were obtained by a detailed examination of selected ESCA peaks. Sputtering was performed on two samples to obtain a depth profile of the composition. The EDXA data confirmed the presence of silicon, aluminum, magnesium, calcium, iron, potassium, sulfur, and titanium while chlorine was detected in some samples. The EDXA data for individual particles exhibited marked particle to particle compositional variation. SEM studies demonstrated that the morphology of FBC samples was different from that of all of the conventional combustor samples examined.

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Scanning Electron Microscopy and X-ray Diffraction in the Determination of Macroelements in Soil and Plants

Communications in Soil Science and Plant Analysis ◽

10.1080/00103624.2019.1589491 ◽

2019 ◽

Vol 50 (7) ◽

pp. 878-893 ◽

Cited By ~ 1

Author(s):

Krasimir Ivanov ◽

Penka Zaprjanova ◽

Violina Angelova ◽

Stefan Krustev

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

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Mineralogical, Microstructural and Compressive Strength Characterization of Fly Ash as Materials in Geopolymer Cement

Elkawnie ◽

10.22373/ekw.v7i1.7787 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Cut Rahmawati ◽

Sri Aprilia ◽

Taufiq Saidi ◽

Teuku Budi Aulia

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Compressive Strength ◽

Fourier Transform ◽

Fly Ash ◽

X Ray Diffraction ◽

Bending Vibration ◽

X Ray ◽

Geopolymer Cement ◽

Scanning Electron

Abstract: This study was designed to examine the mineral, microstructural, and mechanical strength properties of fly ash and its feasibility as a raw material for geopolymer cement. The study used an experimental method by examining the characteristics of fly ash by X-ray Fluorescence Spectrometer (XRF), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), hydrometer method, Scanning electron microscopy (SEM), and compressive strength testing. For creating the geopolymer cement paste, a concentration of NaOH 10M was used, with a ratio of water/solid = 0.4 and a ratio of Na2SiO3/NaOH = 1 using curring at room temperature. The results showed the geopolymer pastes have a compressive strength of 18.1 MPa and 21.5 MPa after 7 days and 28 days. The XRD results showed a decrease in the peak of 2θ at 26.54° because the amorphous part had transformed into a C-S-H solution in geopolymer cement. This finding was supported by the FTIR spectra results showing Si-O-Si bending vibration and the functional group of AlO2. It showed that Nagan Raya fly ash-based geopolymer is a potential construction material.Abstrak: Penelitian ini dirancang untuk mendapatkan sifat mineral, mikrostruktural, dan kekuatan mekanis dari fly ash serta kesesuaiannya sebagai material dasar pada semen geopolimer. Metode penelitian yang digunakan adalah metode eksperimen dengan cara menguji karakteristik dari fly ash dengan pengujian X-ray Fluorescense Spectrometer (XRF), Fourier transform infrared (FTIR) spectoscopy, X-ray diffraction (XRD), hydrometer method, Scanning electron microscopy (SEM) dan kuat tekan. Untuk pembuatan pasta semen geopolimer digunakan konsentrasi NaOH 10 M, rasio water/solid 0,4 dan rasio Na2SiO3/NaOH = 1 dengan perawatan pada suhu kamar. Hasil menunjukkan setelah 7 hari pasta geopolimer memiliki kuat tekan 18,1 MPa dan 21,5 MPa pada 28 hari. Hasil XRD menunjukkan adanya penurunan puncak 2θ pada 26,54° ini disebabkan karena bagian amorf dari fly ash telah menjadi larutan C-S-H pada semen geopolimer. Hasil ini diperkuat dengan analisis FTIR spectra yang menunjukkan adanya Si-O-Si bending vibration dan gugus fungsi dari AlO2. Hasil menunjukkan fly ash dari Nagan Raya potensial sebagai bahan material konstruksi berbasis geopolimer.

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