scholarly journals Assessment of Graphitized Coal Ash Char Concentrates as a Potential Synthetic Graphite Source

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 986
Author(s):  
Charlotte Badenhorst ◽  
Cláudia Santos ◽  
Juan Lázaro-Martínez ◽  
Barbara Białecka ◽  
Mihai Cruceru ◽  
...  
Keyword(s):  
Raw Materials ◽  
Coal Ash ◽  
Proximate Analysis ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Natural Graphite ◽  
X Ray ◽  
Petrographic Analyses ◽  
Synthetic Graphite ◽  
Magnetic Resonance Scanning

Coal ash char concentrates from four countries (Portugal, Poland, Romania, and South Africa) were prepared, characterised, and graphitized under the scope of the Charphite project (Third ERA-MIN Joint Call (2015) on the Sustainable Supply of Raw Materials in Europe). Coal ash chars may be a secondary raw material to produce synthetic graphite and could be an alternative to natural graphite, which is a commodity with a high supply risk. The char concentrates and the graphitized material derived from the char concentrates were characterised using proximate analysis, X-ray fluorescence, X-ray diffraction (structural), Raman microspectroscopy, solid-state nuclear magnetic resonance, scanning electron microscopy, and petrographic analyses to determine if the graphitization of the char was successful, and which char properties enhanced or hindered graphitization. Char concentrates with a lower proportion of anisotropic particles and a higher proportion of mixed porous particles showed greater degrees of graphitization. It is curious to see that embedded Al2O3 minerals, such as glass and clay, influenced graphitization, as they most likely acted as catalysts for crystal growth in the basal direction. However, the graphitized samples, as a whole, do not compare well against a reference natural graphite sample despite some particles in select char concentrates appearing to be graphitized following graphitization.

scholarly journals Improving the quality of silicon metal by the method of x-ray radiometric separation of raw material and finished products

2020 ◽  
Vol 24 (5) ◽  
pp. 1137-1149
Author(s):  
Nikolay Zobnin ◽  
◽  
Sergey Korobko ◽  
Dmitry Vetkovsky ◽  
Andrey Moiseev ◽  
...  
Keyword(s):  
Raw Materials ◽  
Coal Ash ◽  
Product Yield ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Fe2o3 Content ◽  
X Ray ◽  
Initial Iron ◽  
Fluorescence Spectrometer

In this research, we investigate the process of X-ray radiometric separation of both raw materials (quartz, carbonaceous reducing agent) used for silicon smelting in ore-smelting furnaces and the resulting smelting products. The research objects were quartz from the Aktas field (Kazakhstan), coal from the Shubarkol field and silicon metal of various grades smelted at the Tau-Ken Temir LLP (Karaganda, Kazakhstan). X-ray diffraction analysis was performed using a Philips powder diffractometer. To determine the SiO2 and Fe2O3 content, an ARL PERFORM’X X-ray fluorescence spectrometer was used. To remove impurities, a СРF1-150М single-strand radiometric separator was used. We found that the radiometric separation of original quartz samples with the Fe2O3 content of ~ 0.1-0.15% produces pure quartz with the Fe2O3 content of ≤ 0.05% and a yield of 65-70%. Provided that the Fe2O3 content in the original quartz sample does not exceed 0.5%, concentrates with the Fe2O3 content of 0.05% and a yield of 35-55% can be obtained. The yield of pure quartz with the Fe2O3 content of 0.01% does not exceed 15-20%. The use of radiometric separation is established to reduce the amount of phosphorus in the final product by 2-3 times. This method is effective for obtaining coal concentrates of varying ash content (2.0, 4.1 and 7.3%); the resulting concentrated product obtained with a yield of 25% contains 1.5% of ash. Separation of silicon metal (with the initial iron content of 1.2-1.5%) yields a product matching silicon grade 773 (product yield ~ 50%), 553 (~ 35%) or 441 (20%). It is concluded that radiometric separation allows the content of impurities in quartz, silicon metal and coal ash to be reduced, thus facilitating the production of higher-grade silicon.

scholarly journals Use of basaltic waste as red ceramic raw material

Cerâmica ◽  
2016 ◽  
Vol 62 (362) ◽  
pp. 157-162 ◽  
Author(s):  
T. M. Mendes ◽  
G. Morales ◽  
P. J. Reis
Keyword(s):  
Size Distribution ◽  
Mechanical Performance ◽  
Raw Materials ◽  
Raw Material ◽  
Metropolitan Region ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructure Evaluation ◽  
Firing Shrinkage ◽  
Physical And Chemical

Abstract Nowadays, environmental codes restrict the emission of particulate matters, which result in these residues being collected by plant filters. This basaltic waste came from construction aggregate plants located in the Metropolitan Region of Londrina (State of Paraná, Brazil). Initially, the basaltic waste was submitted to sieving (< 75 μm) and the powder obtained was characterized in terms of density and particle size distribution. The plasticity of ceramic mass containing 0%, 10%, 20%, 30%, 40% and 50% of basaltic waste was measured by Atterberg method. The chemical composition of ceramic formulations containing 0% and 20% of basaltic waste was determined by X-ray fluorescence. The prismatic samples were molded by extrusion and fired at 850 °C. The specimens were also tested to determine density, water absorption, drying and firing shrinkages, flexural strength, and Young's modulus. Microstructure evaluation was conducted by scanning electron microscopy, X-ray diffraction, and mercury intrusion porosimetry. Basaltic powder has similar physical and chemical characteristics when compared to other raw materials, and contributes to ceramic processing by reducing drying and firing shrinkage. Mechanical performance of mixtures containing basaltic powder is equivalent to mixtures without waste. Microstructural aspects such as pore size distribution were modified by basaltic powder; albite phase related to basaltic powder was identified by X-ray diffraction.

Effect of Barium Aluminates on Acid Resistance of Fracturing Proppants

2011 ◽  
Vol 383-390 ◽  
pp. 3291-3297
Author(s):  
Shiao Zhao ◽  
Bo Lin Wu ◽  
Shuo Qin ◽  
Yan Rong Zhao ◽  
Zu Sheng Hu
Keyword(s):  
Mass Fraction ◽  
Barium Carbonate ◽  
Raw Materials ◽  
Acid Resistance ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Free System ◽  
X Ray ◽  
Acid Solubility ◽  
Industrial Standards

In order to explore the effect of removing siliceous components on acid resistance of fracturing proppants, acid resistance of fracturing proppants in a new silicon-free system was studied in this paper. The fracturing proppants were made by pressureless sintering using high-purity alumina and barium carbonate as the basic raw material. Acid resistance test was carried out in 12 wt% HCl + 3 wt% HF at 65 oC for 30 minutes according to The Petroleum and Gas Industrial Standards of China (SY/T5108-2006) and morphology, structure and chemical analysis of the samples were investigated using X-ray diffraction and scanning electron microscopy. Experiments show that fracturing proppants that contain barium aluminates have better acid resistance. The acid solubility of the samples is less than 3%, especially when the content of barium carbonate is about 10% (mass fraction, the same below), the acid solubility of the sample reaches 0.52% which is far beyond the demands (5%) of the Standards of SY/T5108-2006. Results prove that the removal of siliceous components of raw materials can prominently improve the acid resistance of fracturing proppants. It can provide a new referential thought for improving the acid resistance of fracturing proppants.

scholarly journals Modifying admixtures to cement compositions produced from local raw materials

2018 ◽  
Vol 143 ◽  
pp. 02006
Author(s):  
Daria Vasileva ◽  
Egor Protodiakonov ◽  
Anastasia Egorova ◽  
Svetlana Antsupova
Keyword(s):  
Cement Paste ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Raw Material ◽  
Free Calcium ◽  
Hardened Cement ◽  
X Ray Diffraction ◽  
Hardened Cement Paste ◽  
X Ray ◽  
Insoluble Compounds

Durability of hardened cement paste depends on chemical and mineralogical composition of Portland cement. The main factor for hardened cement paste is higher content of calcium aluminate and free calcium hydroxide, binding of which into water-insoluble compounds causes increase in resistance to water, frost and corrosion. The purpose of this research is to develop modifying admixtures to cement compositions based on local raw material - rock sand. Chemical and mineralogical properties of the source materials were studied using X-ray spectroscopy and X-ray diffraction analysis. Standard methods were used for defining physico-mechanical properties of sand and binder. Influence of the degree of mechanochemical activation of modifying admixture on the properties of binder and hardened cement paste made on its basis was studied. Research methods of scanning electron microscopy and spectral measurements were applied. The possibility of using admixture based on rock sand as a modifier was determined, its usage providing increase of strength, sulphate and frost resistance, which causes higher durability of cement concrete.

Size Effect of Expandable Graphite

2012 ◽  
Vol 499 ◽  
pp. 72-75 ◽  
Author(s):  
Yan Lu
Keyword(s):  
Particle Size ◽  
Raman Spectroscopy ◽  
Raw Materials ◽  
Structural Disorder ◽  
Expandable Graphite ◽  
X Ray Diffraction ◽  
Natural Graphite ◽  
X Ray ◽  
Intercalating Agents ◽  
Scanning Electron

Using three natural graphites with different particle size, 35, 50 and 80 mesh, as raw materials, expandable graphites were prepared by intercalating, water-washing and drying the natural graphites. The products were characterized by X-ray diffraction, Infrared spectroscopy, scanning electron microscope and Raman spectroscopy. Results show that the structure of expandable graphite is affected strongly by the particle size of natural graphite. With increasing the particle size of natural graphite, for expandable graphite, the expansion degree of graphite flakes along the c-axis and the relative ratio of intercalating agents increase, while the structural disorder increases.

Quality Characterization of Iron Dust Exhaust Thermal as Alternative Ceramic Coating Raw Materials in a Brazilian Company

2014 ◽  
Vol 1077 ◽  
pp. 135-138
Author(s):  
Luiz Oliveira Veriano dalla Valentina ◽  
Marilena Valadares Folgueras ◽  
Wanessa Rejane Knop ◽  
Maria Cristina Pacheco do Nascimento ◽  
Glaucia Aparecida Prates
Keyword(s):  
Ceramic Coating ◽  
Raw Materials ◽  
Ceramic Materials ◽  
Raw Material ◽  
Silica Sand ◽  
Commercial Application ◽  
X Ray Diffraction ◽  
X Ray ◽  
Materials Used

As the raw materials used in the ceramic materials manufacturing are natural, it is important to use them as a alternative materials, thus decreasing the elements demand taken from nature. This paper aims the characterization of foundry solid powder exhaust from a brazilian company located in Joinville - SC as an alternative raw material for ceramic coating by X-ray diffraction (XRD), thermal analysis (DSC) and thermogravimetric (TG). The dust depletion is caused in the manufacturing mold sand process, when the bentonita (clay), silica sand and coal during the metal parts production are mixed in green sand production. The raw materials were characterized through X-ray diffraction (XRD), thermal (DSC) and thermogravimetric analisys (TG). The atomized powder thermogravimetric analysis curve shows three intervals associated with the mass loss and it is typical of clay commercial application.

scholarly journals Characterization of Limestone as Raw Material to Hydrated Lime

2018 ◽  
Vol 34 ◽  
pp. 02042 ◽  
Author(s):  
Rajeb Salem Hwidi ◽  
Tengku Nuraiti Tengku Izhar ◽  
Farah Naemah Mohd Saad
Keyword(s):  
Raw Materials ◽  
Hydrated Lime ◽  
Raw Material ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Main Chemical Composition ◽  
The Difference

In Malaysia, limestone is essentially important for the economic growth as raw materials in the industry sector. Nevertheless, a little attention was paid to the physical, chemical, mineralogical, and morphological properties of the limestone using X-ray fluorescence (X-RF), X-ray diffraction (X-RD), Fourier transform infrared spectroscopy (FTIR), and Scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM-EDS) respectively. Raw materials (limestone rocks) were collected from Bukit Keteri area, Chuping, Kangar, Perlis, Malaysia. Lab crusher and lab sieved were utilized to prepare five different size of ground limestone at (75 µm, 150 µm, 225 µm, 300, and 425 µm) respectively. It is found that the main chemical composition of bulk limestone was Calcium oxide (CaO) at 97.58 wt.% and trace amount of MnO, Al2O3, and Fe2O3 at 0.02%, 0.35%, and 0.396% respectively. XRD diffractograms showed characteristic peaks of calcite and quartz. Furthermore, main FTIR absorption bands at 1,419, 874.08 and 712.20 cm-1 indicated the presence of calcite. The micrographs showed clearly the difference of samples particle size. Furthermore, EDS peaks of Ca, O, and C elements confirmed the presence of CaCO3 in the samples.

Soil-Lime Blocks Using Construction Residues - Durability Study

2012 ◽  
Vol 727-728 ◽  
pp. 1422-1427
Author(s):  
Suélen Silva Figueiredo ◽  
Cibelle Guimarães Silva ◽  
Izabelle Marie Trindade Bezerra ◽  
Suellen Lisboa Dias ◽  
Gelmires Araújo Neves ◽  
...  
Keyword(s):  
Construction Industry ◽  
Raw Materials ◽  
Raw Material ◽  
Partial Replacement ◽  
Distribution Analysis ◽  
X Ray Diffraction ◽  
New Techniques ◽  
X Ray ◽  
Curing Period ◽  
Alternative Materials

The construction industry in addition to being considered one of the biggest natural resources consumers is still responsible for generating large quantities of residues. The impacts caused by these residues have motivated research aimed at developing new techniques for reuse and recycling this material by using as raw material to make alternative materials. The introduction of demolition residues (DR) in soil-lime bricks replacing part of the pozzolan becomes possible due to the cementing properties that these residues may present when finely grounded. This study aims to evaluate the durability of soil-lime blocks embedded with demolition residues. For this study the raw materials were characterized by particle size distribution analysis, X-ray diffraction and chemical analysis. Then test specimens were prepared using mixes in a 1:10 ratio of lime:soil and embedded with residue in partial replacement of lime, in the proportions of 25%, 50% and 75% with curing period of 90 days. Later, the test specimens were evaluated for durability. The results showed that soil-lime bricks embedded with contents above 50% of residues had their durability affected.

Chemically Treated Submicron Illite Clays for Product with Improved Strength

2015 ◽  
Vol 1117 ◽  
pp. 152-155
Author(s):  
Liga Grase ◽  
Gundars Mezinskis ◽  
Inta Vitina
Keyword(s):  
Electron Microscopy ◽  
Raw Materials ◽  
Nitrogen Adsorption ◽  
Raw Material ◽  
Industrial Minerals ◽  
X Ray Diffraction ◽  
Adsorption Method ◽  
X Ray ◽  
Different Temperatures ◽  
Scanning Electron

A variety of industrial minerals, such as kaolinite, feldspars, and etc., have been used as solid raw materials in the geopolymerization technology. The illite-containing raw material in this study was obtained by the use of sedimentation method. Clay and dust fractions was subjected to the treatment with NaOH alkaline solution and afterwards treated at different temperatures. Results obtained by X-ray diffraction, Scanning electron microscopy, nitrogen adsorption method confirmed the usability of Liepas deposit homogenized gray and red clays for possible realization of geopolymer method.

Research on the Effect of High-Temperature Melting β-SiC by Raw Materials and Power Supply

2017 ◽  
Vol 727 ◽  
pp. 294-296
Author(s):  
Ze Min Wu ◽  
Xiao Gang Wang ◽  
Zi Min Fan ◽  
Li Rong Deng ◽  
Shu He Lu
Keyword(s):  
High Temperature ◽  
Raw Materials ◽  
Electrical Power ◽  
Raw Material ◽  
X Ray Diffraction ◽  
High Quality ◽  
X Ray ◽  
Smelting Method ◽  
Powder Samples ◽  
Temperature Melting

Using high quality carbon raw material,high quality silica raw material , the β-SiC powder are prepared by high-temperature vacuum smelting method. The effects of different materials and electrical power to the product of β-SiC quality has been studied. The microstructure and phase analysis of β-SiC powder samples were observed by Scanning Electron Microscopy and X-ray diffraction. The result shows that the raw materials are better, the product quality are better. In addition, the result also indicates that the β-SiC powder have better quality when the power are 3000W.

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