Interference Films on Glass: II, Some Observations During Acid Leaching of X-Ray Plate Glass

Timahdit oil shale was subjected to firing transformation via ceramics processing followed by alkali activation to synthesis a materials combining the mechanical properties of ceramics and Zeolites. The mineralogical transformations during firing oil shale have been studied. The main crystalline phases found in oil shale ash (OSA) were wollastonite, gehlenite and augite. Modified oil shale ash (MOSA) was obtained with HNO3acid-leaching in the aim to diminish Ca content. Our experimental approach required a NaOH alkaline activating solution with different concentrations (0.5; 1; 2; 4; 6 and 8M). In our study, X-ray diffraction (XDR), Fourier transform infrared (FTIR) and SEM/EDS analysis were used to evaluate the effect of alkali activation on the structural arrangement of the starting materials (OSA and MOSA) in our study. The quantity and the type of the produced zeolites depended critically on the starting materials and on the NaOH concentration.

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Pengaruh Suhu dan Konsentrasi terhadap Proses Pemisahan Nikel dari Logam Pengotor Menggunakan Metode Leaching

FLUIDA ◽

10.35313/fluida.v13i2.2388 ◽

2020 ◽

Vol 13 (2) ◽

pp. 81-92

Author(s):

Ade Yanti Nurfaidah ◽

Dheana Putri Lestari ◽

Rheisya Talitha Azzahra ◽

Dian Ratna Suminar

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Sulfuric Acid ◽

Atmospheric Pressure ◽

Operating Temperature ◽

Acid Leaching ◽

X Ray Diffraction ◽

X Ray ◽

Pressure Acid Leaching ◽

Scanning Electron

Abstrak Nikel merupakan unsur logam yang penggunaannya sudah dikenal dalam industri, terutama pada pelapisan logam dan paduan. Pengolahan nikel dari bijih nikel laterit (jenis Limonit) menggunakan proses hidrometalurgi Atmospheric Pressure Acid Leaching (APAL) yang dinilai lebih ekonomis karena pemakaian energi dan biaya operasional cukup rendah. Media pelarut yang digunakan berupa larutan asam sulfat (H2SO4). Sebelum dilakukan pengolahan, karakterisasi bijih dilakukan menggunakan X-Ray Diffraction (XRD), X-Ray Flourscence (XRF), dan Scanning Electron Microscopy (SEM). Metode penelitian yang dilakukan yaitu literature review. Hasil review dari beberapa artikel jurnal menunjukkan bahwa kadar nikel yang terkandung pada suatu bijih sekitar 1,42%, 2,94 dan 0,95% serta sisanya adalah pengotor. Kondisi operasi yang tepat akan menghasilkan pemurnian nikel yang cukup tinggi. Parameter kondisi operasi yang dapat memengaruhi proses pemisahan nikel diantaranya suhu operasi yang ditunjukan dengan semakin meningkatnya % ekstraksi nikel seiring dengan kenaikan suhu. Selain suhu operasi, konsentrasi pelarut juga salah satu parameter yang mempengaruhi % ekstraksi karena semakin tinggi ion H+ akan memudahkan proses pelarutan sehingga akan mengikat Nikel Oksida yang terdapat pada bijih. Suhu paling optimal untuk menghasilkan nikel dengan kemurnian tinggi dalam operasi pelindian atmosferik adalah 90°C dan konsentrasi asam sulfat 5 M. Kata Kunci: Nikel, pelindian, suhu, konsentrasi Abstract Nickel is a metal element whose use is well known in industry, especially in metal and alloy plating. The processing of nickel from laterite nickel ore (Limonite type) uses a hydrometallurgical process of Atmospheric Pressure Acid Leaching (APAL) which is considered more economical because energy consumption and operational costs are quite low. The solvent medium used is a solution of sulfuric acid (H2SO4). Prior to processing, ore characterization was carried out using X-Ray Diffraction (XRD), X-Ray Flourscence (XRF), and Scanning Electron Microscopy (SEM). The research method literature review article. The results of reviews from several journal articles show that the nickel content contained in an ore is around 1.42%, 2.94% and 0.95% and the rest is impurity. The right operating conditions will result in relatively high nickel refining. The operating condition parameters that can affect the nickel separation process include the operating temperature which is indicated by the increasing % nickel extraction along with the increase in temperature. In addition to operating temperature, solvent concentration is also one of the parameters that affects the% extraction because the higher the H+ ion will facilitate the dissolving process so that it will bind to the Nickel Oxide contained in the ore. The optimal temperature to produce high-purity nickel in atmospheric leaching operations is 90°C and a sulfuric acid concentration of 5 M. Keywords: Nickel, leaching, temperature, concentration

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Research of Polymetallic Sulfide Industrial Waste Nitric Acid Treatment

KnE Materials Science ◽

10.18502/kms.v2i2.966 ◽

2017 ◽

Vol 2 (2) ◽

pp. 174

Author(s):

Rogozhnikov D.A. ◽

Dizer O.A. ◽

Shoppert A.A.

Keyword(s):

Nitric Acid ◽

Industrial Waste ◽

Mutual Influence ◽

Acid Leaching ◽

Raw Material ◽

X Ray Diffraction ◽

Mathematical Methods ◽

X Ray ◽

Nitric Acid Leaching ◽

Kinetic Features

<p>Thermodynamic and kinetic features studies of polymetallic sulfide industrial waste nitric acid leaching were carried out. Elemental and phase composition of investigated raw material were studied with X-ray diffraction and electron microscopy methods. Calculations of the Gibbs energy change for the likely reactions of sulfide minerals with nitric acid were performed. In order to determine the most probable conditions of the sulfide industrial waste leaching in nitric acid, as well as the mutual influence of the produced pulp components on the performance of the process, the kinetics evaluation of multicomponent sulfide industrial waste in a nitric medium was studied using mathematical methods.</p>

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Use of Retorted Shale as Sulfur Adsorbent

Materials Science Forum ◽

10.4028/www.scientific.net/msf.930.562 ◽

2018 ◽

Vol 930 ◽

pp. 562-567

Author(s):

Rodolfo Luiz Bezerra de Araújo Medeiros ◽

Maria de Fátima Dantas e Silva ◽

Rodrigo César Santiago ◽

Gilvan Pereira de Figueredo ◽

Heloísa Pimenta de Macedo ◽

...

Keyword(s):

Acid Leaching ◽

Gas Production ◽

Liquid Fuels ◽

Test Results ◽

X Ray Diffraction ◽

Adsorptive Desulfurization ◽

Wet Impregnation ◽

X Ray ◽

Chemically Modified ◽

Alternative Material

The aim of this work is to use a residue from shale gas production, known as retorted shale (RS), as an alternative material for processes of sulfur adsorptive desulfurization in liquid fuels such as gasoline or diesel. Therefore, retorted shale samples were chemically modified. Two methods were applied: acid leaching and impregnation. The first method (RS-HCl) was an acid treatment with HCl solution (3M) in proportion of 1.5: 10. The second method (RS-Fe) was a wet impregnation of 20%wt. of Fe followed by calcination at 700°C for 2 h. The adsorbents were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The adsorption tests were performed using a solution of n-heptane and thiophene to simulate a fuel with an initial concentration of 500 ppm of sulfur. The results showed that both methods significantly altered the structure of the retorted shale, mainly the amount of Fe2O3. The adsorption test results indicated that the adsorbents prepared can remove up to 90% of the sulfur present.

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X-ray diffraction line profile analysis of acid-resistant goethite in Western Australian nickel laterite ore

Journal of Applied Crystallography ◽

10.1107/s1600576715006275 ◽

2015 ◽

Vol 48 (3) ◽

pp. 814-826

Author(s):

Xiaodong Wang ◽

Jian Li ◽

Robbie G. McDonald ◽

Arie van Riessen ◽

Robert D. Hart

Keyword(s):

Size Distribution ◽

Size Fraction ◽

Acid Leaching ◽

Domain Size ◽

Line Profile Analysis ◽

Nickel Laterite ◽

X Ray ◽

Peak Broadening ◽

Nickel Laterite Ore ◽

Laterite Ore

The goethite peaks in synchrotron and laboratory X-ray powder diffraction (XRPD) patterns of an acid-resistant nickel laterite ore sample from a site in Western Australia exhibit a `super-Lorentzian' shape. The method for extracting the coherently scattering domain size distribution published by Leoni & Scardi [J. Appl. Cryst.(2004),37, 629–634] is adapted to fit the asymmetric goethite peak profiles, allowing the refinement of lattice parameters for multiple goethite structural models while maintaining their relationships. The anisotropic peak broadening due to the acicular shape of the goethite crystals is addressed using spherical harmonics predefined from an XRPD pattern of a synthetic goethite sample. A bimodal coherently scattering domain size distribution of goethite crystals is predicted from the goethite profile fitting and agrees with previous transmission electron microscopy findings that two goethite populations with different domain sizes and metal substitutions exist in the ore sample. The small goethite size fraction dissolved slowly during atmospheric acid leaching, while the large goethite fraction barely dissolved. Caustic pre-treatment by KOH digestion significantly enhanced the acid-leaching performance of the small goethite fraction, but had no effect on the large goethite fraction. This study demonstrates that quantitative phase analysis on designated goethite size fractions can successfully fit the super-Lorentzian shaped line profiles of natural goethite crystals with a confirmed bimodal domain size distribution.

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Fabrication of Porous YSZ from ZnO-YSZ Cermet

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.235 ◽

2007 ◽

Vol 124-126 ◽

pp. 235-238

Author(s):

Moon Jin Hwang ◽

Chong Soo Han

Keyword(s):

Electron Microscope ◽

Gas Permeability ◽

Acid Leaching ◽

Yttria Stabilized Zirconia ◽

X Ray Diffraction ◽

Stabilized Zirconia ◽

Scanning Electron Microscope Image ◽

X Ray ◽

Electron Microscope Image ◽

Scanning Electron

Porous YSZ(8 mol% yttria-stabilized zirconia) was prepared by an acid leaching of ZnO-YSZ composite. The ZnO-YSZ composites were obtained by two different methods, a 1450 °C sintering of the mechanical mixture of ZnO and YSZ powders or a decomposition of Zn(NO3)2 deposited on YSZ and a subsequent sintering. The XRD (X-ray diffraction) pattern of the composite indicated that it was a mixture of ZnO and YSZ even after the sintering. Sharp edge or round edge of YSZ was observed in SEM (Scanning Electron Microscope) image of the porous-YSZ from the mixture of ZnO and YSZ, or Zn(NO3)2 deposited on YSZ, respectively. The porous YSZ from the composite having ZnO component greater than 60 wt% shows low mechanical strength. As the ZnO content of the composite increased, the porosity and gas permeability of the porous YSZ increased. From the result, it was suggested that ZnO is a candidate to generate pores in YSZ bulk or membrane.

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Investigation on the quality of silicon extracted from the Padma river sand using magnesio-aluminothermic process

Bangladesh Journal of Physics ◽

10.3329/bjphy.v26i2.49304 ◽

2020 ◽

Vol 26 (2) ◽

pp. 33-40

Author(s):

Abdul Kuddus ◽

SM Mahabubuzzaman ◽

Abu Bakar Md Ismail

Keyword(s):

Polycrystalline Silicon ◽

Low Cost ◽

Acid Leaching ◽

Eutectic Mixture ◽

X Ray Diffraction ◽

River Sand ◽

X Ray ◽

Aluminothermic Reaction ◽

Padma River

Investigation on the quality of the extracted Silicon (Si) from the sand of the Padma river of Bangladesh using the Magnesio-Aluminothermic process has been presented in this work. Magnesio-Aluminothermic process, which is low-energy, low-cost and CO2 free compared to conventional carbothermic process, was used for the extraction of Si from the sand. By performing the thermite process, Si was extracted as a eutectic mixture of Aluminium and Si, following that, several cycles of acid leaching were used to obtain highly pure polycrystalline silicon. After grinding the cleaned sand and making a homogeneous mixture with associated chemicals and ignition materials, modified Aluminothermic reaction was performed to produce a eutectic mixture of Si and Al. Grinded eutectic mixture of Si and Al was then purified with acid leaching and finally above 97% pure crystalline Si was extracted. XRD (X-ray diffraction) and Raman Spectroscopy confirmed the polycrystalline nature of Si where XRF (X-ray fluorescence) and EDX (Energy Dispersive X-ray Spectroscopy) corroborated the high purity of extracted Si describing the chemical composition. Bangladesh Journal of Physics, 26(2), 33-40, December 2019

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Effect of Oxalic Acid Leaching on Photocatalytic Activity of Natural Sphalerite

10.21203/rs.3.rs-117664/v1 ◽

2020 ◽

Author(s):

Chukwunonso Onyenanu ◽

Lovet Emembolu

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Visible Light ◽

Irradiation Time ◽

Acid Leaching ◽

Blue Dye ◽

Light Illumination ◽

X Ray Diffraction ◽

X Ray ◽

Visible Light Illumination

Abstract Photocatalytic activity of the natural semiconducting sphalerite mineral from Abuni, Nasarawa State, Nigeria was studied for the degradation of methylene blue (MB). Natural Sphalerite as a visible – light responsive photocatalyst was characterized by X ray diffraction (XRD), X ray fluorescence (XRF) and surface area analysis. To further enhance the photocatalytic activity of natural Sphalerite, the chemical composition of the sphalerite was varied via leaching with oxalic acids. The photocatalytic activity of the Natural sphalerite, leached sphalerite and as well as the calcined leachates was tested for MB degradation under visible light illumination. The result shows a very high percentage of MB degradation by natural sphalerite after 60mintues of light irradiation time. A composite of ZnO -α –Fe2O3 -ϒ-Fe2O3 with traces amount of MoO and MnO2 was synthesized by calcination of the obtained leachates at 1000°C for 4hours. The photocatalytic degradation of methylene blue dye follows pseudo first order kinetics.

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Kinetics Study of Al Extraction from Desilicated Coal Fly Ash by NaOH at Atmospheric Pressure

Materials ◽

10.3390/ma14247700 ◽

2021 ◽

Vol 14 (24) ◽

pp. 7700

Author(s):

Andrei Shoppert ◽

Irina Loginova ◽

Dmitry Valeev

Keyword(s):

Fly Ash ◽

Atmospheric Pressure ◽

Inductively Coupled Plasma ◽

Coal Fly Ash ◽

Acid Leaching ◽

Emission Spectrometry ◽

Pressure Leaching ◽

Water Leaching ◽

X Ray ◽

Promising Source

The most promising source of alumina in the 21st century is the coal fly ash (CFA) waste of coal-fired thermal plants. The methods of alumina extraction from CFA are often based on the pressure alkaline or acid leaching or preliminary roasting with different additives followed by water leaching. The efficiency of the alumina extraction from CFA under atmospheric pressure leaching is low due to the high content of acid-insoluble alumina phase mullite (3Al2O3·2SiO2). This research for the first time shows the possibility of mullite leaching under atmospheric pressure after preliminary desilication using high liquid to solid ratios (L:S ratio) and Na2O concentration. The analysis of the desilicated CFA (DCFA) chemical and phase composition before and after leaching has been carried out by inductively coupled plasma optical emission spectrometry (ICP-OES) and X-ray diffraction (XRD). The morphology and elemental composition of solid product particles has been carried out by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). An automated neural network and a shrinking core model (SCM) were used to evaluate experimental data. The Al extraction efficiency from DCFA has been more than 84% at T = 120 °C, leaching time 60 min, the L/S ratio > 20, and concentration of Na2O-400 g L−1. The kinetics analysis by SCM has shown that the surface chemical reaction controls the leaching process rate at T < 110 °C, and, at T > 110 °C after 15 min of leaching, the process is limited by diffusion through the product layer, which can be represented by titanium compounds. According to the SEM-EDX analysis of the solid residue, the magnetite spheres and mullite acicular particles were the main phases that remained after NaOH leaching. The spheric agglomerates of mullite particles with non-porous surface have also been found.

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