Mineralogical-Geochemical Study of Corroded Iron-Based Metals from a Salt Mine Environment

CORROSION ◽  
10.5006/3493 ◽  
2020 ◽  
Vol 76 (7) ◽  
pp. 666-677
Author(s):  
Zbigniew Sawłowicz ◽  
Łukasz Malinowski ◽  
Andy Giże ◽  
Jan Stanek ◽  
Jerzy Przybyło
Keyword(s):  
Chloride Content ◽  
Outer Zone ◽  
Chemical Compositions ◽  
Salt Mine ◽  
X Ray Diffraction ◽  
Geochemical Study ◽  
Internal Zone ◽  
Advanced Stages ◽  
Iron Artifacts ◽  
Iron Bearing

Metal fragments (pipe, chain, valves), at advanced stages of corrosion, were collected underground in the Wieliczka salt mine. Macroscopically distinct zones of corroded material, as well as black blisters on the surface of different metal fragments, were studied using scanning electron microscopy with energy dispersive spectrometry (SEM-EDS), x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and Mössbauer spectroscopy (MS). SEM-EDS studies showed various morphological forms with different chemical compositions. The original outer zone of the iron artifacts is mainly composed of aggregates of needle-shaped goethite crystals with idiomorphic crystals of halite. A subsequent zone, toward the inner margin, is composed mainly of fine granular aggregates of magnetite. Goethite (α-FeOOH) and akaganeite (β-FeOOH) form spherical, fibrous, and structureless aggregates in the next internal zone. Forms of aggregates seem to depend on the chloride content, 1 wt% to 3.5 wt% Cl in the structureless aggregates and 5 wt% to 9 wt% Cl in the regular ones. In addition, in the internal zone crystals of lepidocrocite form rosettes. Blisters are built of the acicular akaganeite crystals, which form fibrous aggregates in the shell and spherical ones in the interior. The relative concentrations of iron bearing minerals in the studied zones, i.e., akaganeite, hematite, goethite, magnetite, and lepidocrocite are established. Where they dominate, the zones are: black (magnetite), orange (goethite, lepidocrocite, akaganeite), and light brown (goethite).

scholarly journals New Insights into the Crystal Chemistry of Elpidite, Na2Zr[Si6O15]·3H2O and (Na1+YCax□1−X−Y)Σ=2Zr[Si6O15]·(3−X)H2O, and Ab Initio Modeling of IR Spectra

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2160
Author(s):  
Alexander Bogdanov ◽  
Ekaterina Kaneva ◽  
Roman Shendrik
Keyword(s):  
Ir Spectra ◽  
Structural Models ◽  
Chemical Characterization ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Special Group ◽  
X Ray ◽  
Influence Of Water ◽  
Radioactive Species

Elpidite belongs to a special group of microporous zirconosilicates, which are of great interest due to their capability to uptake various molecules and ions, e.g., some radioactive species, in their structural voids. The results of a combined electron probe microanalysis and single-crystal X-ray diffraction study of the crystals of elpidite from Burpala (Russia) and Khan-Bogdo (Mongolia) deposits are reported. Some differences in the chemical compositions are observed and substitution at several structural positions within the structure of the compounds are noted. Based on the obtained results, a detailed crystal–chemical characterization of the elpidites under study was carried out. Three different structure models of elpidite were simulated: Na2ZrSi6O15·3H2O (related to the structure of Russian elpidite), partly Ca-replaced Na1.5Ca0.25ZrSi6O15·2.75H2O (close to elpidite from Mongolia), and a hypothetical CaZrSi6O15·2H2O. The vibration spectra of the models were obtained and compared with the experimental one, taken from the literature. The strong influence of water molecule vibrations on the shape of IR spectra of studied structural models of elpidite is discussed in the paper.

scholarly journals Conversion of jet biofuel range hydrocarbons from palm oil over zeolite hybrid catalyst

2021 ◽  
Vol 11 ◽  
pp. 184798042098153
Author(s):  
Norsahika Mohd Basir ◽  
Norkhalizatul Akmal Mohd Jamil ◽  
Halimaton Hamdan
Keyword(s):  
Palm Oil ◽  
Aromatic Hydrocarbons ◽  
Zeolite Y ◽  
Zeolite Catalysts ◽  
Gas Chromatography Mass Spectrometry ◽  
Chemical Compositions ◽  
Hybrid Catalyst ◽  
X Ray Diffraction ◽  
Temperature Programmed ◽  
Reaction Routes

The catalytic conversion of palm oil was carried out over four zeolite catalysts—Y, ZSM-5, Y-ZSM-5 hybrid, and Y/ZSM-5 composite—to produce jet biofuel with high amount of alkanes and low amount of aromatic hydrocarbons. The zeolite Y-ZSM-5 hybrid catalyst was synthesized using crystalline zeolite Y as the seed for the growth of zeolite ZSM-5. Synthesized zeolite catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, and temperature programmed desorption of ammonia, while the chemical compositions of the jet biofuel were analyzed by gas chromatography-mass spectrometry (GC-MS). The conversion of palm oil over zeolite Y resulted in the highest yield (42 wt%) of jet biofuel: a high selectivity of jet range alkanes (51%) and a low selectivity of jet range aromatic hydrocarbons (25%). Zeolite Y-ZSM-5 hybrid catalyst produced a decreased percentage of jet range alkane (30%) and a significant increase in the selectivity of aromatic hydrocarbons (57%). The highest conversion of palm oil to hydrocarbon compounds was achieved by zeolite Y-ZSM-5 hybrid catalyst (99%), followed by zeolite Y/ZSM-5 composite (96%), zeolite Y (91%), and zeolite ZSM-5 (74%). The reaction routes for converting palm oil to jet biofuel involve deoxygenation of fatty acids into C15–C18 alkanes via decarboxylation and decarbonylation, catalytic cracking into C8–C14 alkanes, and cycloalkanes as well as aromatization into aromatic hydrocarbon.

scholarly journals Thermal History of Matrix Forsterite Grains from Murchison Based on High-resolution Tomography

2021 ◽  
Vol 922 (2) ◽  
pp. 256
Author(s):  
Giulia Perotti ◽  
Henning O. Sørensen ◽  
Henning Haack ◽  
Anja C. Andersen ◽  
Dario Ferreira Sanchez ◽  
...  
Keyword(s):  
High Resolution ◽  
Electron Density ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Maps ◽  
Thermally Processed ◽  
The Matrix ◽  
History Of ◽  
Chondrule Formation

Abstract Protoplanetary disks are dust- and gas-rich structures surrounding protostars. Depending on the distance from the protostar, this dust is thermally processed to different degrees and accreted to form bodies of varying chemical compositions. The primordial accretion processes occurring in the early protoplanetary disk such as chondrule formation and metal segregation are not well understood. One way to constrain them is to study the morphology and composition of forsteritic grains from the matrix of carbonaceous chondrites. Here, we present high-resolution ptychographic X-ray nanotomography and multimodal chemical microtomography (X-ray diffraction and X-ray fluorescence) to reveal the early history of forsteritic grains extracted from the matrix of the Murchison CM2.5 chondrite. The 3D electron density maps revealed, at unprecedented resolution (64 nm), spherical inclusions containing Fe–Ni, very little silica-rich glass and void caps (i.e., volumes where the electron density is consistent with conditions close to vacuum) trapped in forsterite. The presence of the voids along with the overall composition, petrological textures, and shrinkage calculations is consistent with the grains experiencing one or more heating events with peak temperatures close to the melting point of forsterite (∼2100 K), and subsequently cooled and contracted, in agreement with chondrule-forming conditions.

The Production Technology of, and Trade in, Egyptian Blue Pigment in the Roman World

2007 ◽  
Author(s):  
Michael Tite ◽  
Gareth Hatton
Keyword(s):  
Roman Empire ◽  
Raw Materials ◽  
Eastern Mediterranean ◽  
Blue Pigment ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Egyptian Blue ◽  
Intimate Mixture ◽  
Materials Used ◽  
Scanning Electron

Egyptian blue was first used as a pigment on tomb paintings in Egypt from around 2300 BC, and during the subsequent 3,000 years, its use both as a pigment and in the production of small objects spread throughout the Near East and Eastern Mediterranean and to the limits of the Roman Empire. During the Roman period, Egyptian blue was distributed in the form of balls of pigment up to about 15mm across, and appears to have been the most common blue pigment to be used on wall paintings throughout the Empire. Egyptian blue was both the first synthetic pigment, and one of the first materials from antiquity to be examined by modern scientific methods. A small pot containing the pigment that was found during the excavations at Pompeii in 1814 was examined by Sir Humphrey Davy. Subsequently, x-ray diffraction analysis was used to identify the compound as the calcium-copper tetrasilicate C<sub>a</sub>C<sub>u</sub>Si<sub>4</sub>O<sub>10</sub>, and to establish that Egyptian blue and the rare natural mineral cuprorivaite are the same material. Examination of Egyptian blue samples in cross-section in a scanning electron microscope (SEM) revealed that they consist of an intimate mixture of Egyptian blue crystals (i.e. C<sub>a</sub>C<sub>u</sub>Si<sub>4</sub>O<sub>10</sub>) and partially reacted quartz particles together with varying amounts of glass phase (Tite, Bimson, and Cowell 1984). At this stage it should be emphasized that, in the literature, the term Egyptian blue tends to be used to describe both crystals of calcium-copper tetrasilicate and the bulk polycrystalline material that is used as the pigment and is sometimes referred to as frit. In this chapter, the suffix ‘crystal’ or ‘mineral’ will be added when the former meaning applies, and the suffix ‘pigment’, ‘sample’, or ‘frit’ will be added when the latter meaning applies. For the current study, a small group of Roman Egyptian blue samples were examined using scanning electron microscopy (SEM) with attached analytical facilities. Using the chemical compositions of the samples, together with the description of the manufacture of Egyptian blue given by Vitruvius (Morgan 1960) at the beginning of the first century BC in his Ten Books on Architecture, an attempt is made to identify the raw materials used in the production of Roman Egyptian blue.

Research and Preparation of Silver Free Amorphous Active Brazing Alloy

2015 ◽  
Vol 817 ◽  
pp. 96-103
Author(s):  
Wei Ping Fang ◽  
Yao Yong Yi ◽  
Feng Mei Liu ◽  
Zheng Lin Liu ◽  
Zhen Hua Deng
Keyword(s):  
Bending Strength ◽  
Mechanical Test ◽  
Amorphous Material ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Xrd Pattern ◽  
Spreading Area ◽  
Wetting Ability ◽  
Wetting Contact Angle

A silver free amorphous Cu-35Ti-12Ni active brazing alloy was successfully prepared in this work. The crystallinity, microstructure, and chemical composition were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive spectrometry (EDS), respectively. A typical characteristic peak of amorphous material was observed in the XRD pattern. The microstructures and chemical compositions of the silver free amorphous alloy were uniform. Differential scanning calorimetry (DSC) result shows that the amorphous silver free brazing alloy has higher melting temperature than commercial silver brazing alloy (Ag-26.5Cu-1.5Ti). Wetting contact angle and spreading area on Si3N4 ceramic substrate were used to evaluate the wetting ability of brazing alloy. The wetting angle was smaller than 5o, and the spreading area was 141.6 mm2 at 1100°C. The bending strength of silver free brazing alloy/Si3N4 was also carried out. The mechanical test shows that the amorphous Cu-35Ti-12Ni/Si3N4 has higher joint strength (304.7MPa) than the crystal Cu-35Ti-12Ni/Si3N4 (294.7MPa) at room temperature.

Chlorite crystallinity as an indicator of metamorphic grade of low-temperature meta-igneous rocks: a case study from the Bükk Mountains, Northeast Hungary

Clay Minerals ◽  
1997 ◽  
Vol 32 (2) ◽  
pp. 205-222 ◽  
Author(s):  
P. Árkai ◽  
D. Sadek Ghabrial
Keyword(s):  
Low Temperature ◽  
Electron Microprobe ◽  
Metamorphic Grade ◽  
Igneous Rocks ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Facies Classification ◽  
Increasing Temperature ◽  
Relative Differences

AbstractX-ray diffraction chlorite crystallinity (ChC) indices and major element chemical compositions of chlorites and bulk rocks were determined and correlated in meta-igneous rocks from different Mesozoic formations in various tectonic units of the Bükk Mountains, NE Hungary. The rocks, of basic to acidic compositions, range from ocean-floor metamorphic prehnite-pumpellyite facies (diagenetic zone) through regional metamorphic prehnite-pumpellyite facies (anchizone) up to the regional metamorphic pumpellyite-actinolite and greenschist facies (epizone). As in the case of meta-sedimentary rocks, chlorite crystallinity can be applied as an empirical, complementary petrogenetic tool to determine relative differences in grades of low-temperature meta-igneous rocks. Electron microprobe and XRD data show that ChC is controlled mainly by the decreasing amounts of contaminants (mixed-layered components or discrete, intergrown phases of mostly smectitic composition) in chlorite with advancing metamorphic grade, up to the epizone. The apparent increase in calculated Aliv content of chlorite with increasing temperature is related to the decrease of these contaminants, as stated earlier by Jiang et al. (1994). On the basis of the significant correlations found between ChC and temperatures, derived by the chlorite-Aliv geothermometer of Cathelineau (1988), both methods may be used for estimating the approximate temperatures of metamorphism, in spite of the contrasting interpretation of chemical data from chlorites obtained by electron microprobe analyses. After determining the effects of changing bulk chemistry on chlorite composition and ChC, the chlorite crystallinity method may complement the correlation of the illite crystallinity-based zonal classification of meta-sediments and the mineral facies classification of meta-igneous rocks.

scholarly journals Archaeometric Characterisation of Decorated Pottery from the Archaeological Site of Villa dei Quintili (Rome, Italy): Preliminary Study

Geosciences ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 172 ◽  
Author(s):  
Michela Ricca ◽  
Giuseppe Paladini ◽  
Natalia Rovella ◽  
Silvestro Antonio Ruffolo ◽  
Luciana Randazzo ◽  
...  
Keyword(s):  
Multidisciplinary Approach ◽  
Raw Materials ◽  
Archaeological Site ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
X Ray ◽  
Geochemical Study ◽  
Renaissance Period ◽  
Preliminary Study ◽  
Materials Used

This work focused on the study of decorated pottery dated back to the 16th century from the Roman archaeological site of Villa dei Quintili, a monumental complex located in the south-eastern part of Rome (Italy). A minero-petrographic and geochemical study was undertaken to analyse five archaeological samples in order to define textural features and raw materials used for their production, along with the chemical and physical composition of the superficial decorative glazed coatings. For this purpose, different analytical methods were used, such as polarising optical microscope (POM), X-ray diffraction (XRD), micro-Raman spectroscopy, X-Ray fluorescence (XRF), and electron microprobe analysis coupled with energy dispersive spectrometry (EMPA-EDS). The results of such a multidisciplinary approach allowed us to achieve important results crucial to recognise the shards as majolica of the Renaissance period, improving knowledge about manufacturing processes of these renowned painted ceramic artefacts.

scholarly journals Microstructures and Mechanical Properties of Al/Fe and Cu/Fe Joints by Continuous Drive Friction Welding

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Yanni Wei ◽  
Fu Sun
Keyword(s):  
Tensile Test ◽  
Reaction Layer ◽  
Friction Welding ◽  
Welding Process ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Friction Pressure ◽  
Pure Metals ◽  
Joining Strength

The dissimilar pure metals Al/Fe and Cu/Fe with different metallurgical compatibility were joined by continuous drive friction welding. The friction weldability was investigated. The microstructure of the joining interface was analyzed by scanning electron microscopy, and the chemical compositions were tested by energy-dispersive spectroscopy. The joining strength was evaluated by tensile test, and the fracture was detected by X-ray diffraction analysis. The results show that sound joints of Al/Fe and Cu/Fe can be obtained by continuous drive friction welding process. A discontinuous reaction layer was formed on Al/Fe interface, and no obvious reaction layer appeared on Cu/Fe interface. The tensile strength of the joints increased with increasing friction pressure, and the highest strength could reach up to 70 MPa for Al/Fe joint and 222 MPa for Cu/Fe joint. All the Al/Fe friction-welded samples failed at the friction interface, while the Cu/Fe joint under 36 and 44 MPa friction pressure failed at Cu matrix during the tensile test.

Development of Photoactive Nano TiO2 Thin Film-Geopolymer Based on Laterite Soils Deposit Gowa Regency as Self-Cleaning Material

2019 ◽  
Vol 967 ◽  
pp. 274-280
Author(s):  
Anita Dewi Permatasari ◽  
Nursalfaul Fahira ◽  
Nurul Husna Muslimin ◽  
Subaer
Keyword(s):  
Thin Film ◽  
Milling Process ◽  
The Self ◽  
Alkali Activation ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spray Method ◽  
Self Cleaning ◽  
Uv Lamp

The main objectives of this study is to investigate the properties of photoactive Nano TiO2 thin film-geopolymer based on laterite soils deposit Gowa regency as self-cleaning material. The soil was clean, grounded, sieves 200 mesh and dehydroxylated at 750 for 2 hours. Nano TiO2 was prepared through ball milling process for 10 hours. The geopolymers was synthesized through alkali activation method by adjusting the molar oxide ratios of SiO2/(Al2O3+Fe2O3), Na2O/SiO2 and H2O/Na2O in accordance with the chemical compositions of the soils. Nano TiO2 was added into geopolymers paste at different concentration namely 0.5% and 1.0% (relative to the mass of laterite soils) by using spray method. The self-cleaning properties of the sample were observed by immersing the sample into clays solution then irradiated under UV lamp for 24 hours. The X-Ray Diffraction (XRD) was performed to examine the structure and phase of the sample. The surface morphology of geopolymers was studied by using scanning electron microscopy (SEM). The measurements results showed that photoactive Nano TiO2-geopolymers composite can be applied as self-cleaning materials.

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