Studying of possibility for breakdown of ilmenite concentrate with ammonium sulphate

The data on investigation of the possibility of breakdown of ilmenite concentrate of the Ariadnensky deposit in Primorsky Krai with ammonium sulfate are presented in the article. For study the ilmenite concentrate and ammonium sulfate interaction, the concentrate and (NH4)2SO4 were mixed based on the formation of sulfates of the main components of the concentrate and then double sulfates of the components of the concentrate and ammonium. The interaction was carried out in glassy carbon crucibles, which were placed in a muffle furnace controller company Nabertherm GmbH (Germany). The weight of sample was 10–40 g. Thermogravimetry, X-ray diffraction and atomic absorption analyses were used in the study. It was found that when the temperature of thermal decomposition of (NH4)2SO4 (3000С) is reached, the interaction of the main components of the concentrate with (NH4)2SO4 begins and proceeds in the temperature range of 300-3600С with the formation of a mixture of double salts well soluble in water - ammonium sulfate and iron compounds (NH4)2Fe2(SO4)3 and NH4Fe(SO4)2 and ammonium sulfate and titanyl of the composition (NH4)2TiO(SO4)2. The interaction at a temperature above 3600С leads to thermal decomposition of the formed double sulfates of ammonium and titanyl and ammonium and iron to sulfates and then oxides. It was shown that water leaching of the product of the interaction of ilmenite concentrate with (NH4)2SO4 at 3600С allows to extract practically all titanium and the bulk of iron to water in the form of well soluble double salts. The conditions for the titanium dioxide separation in the form of anatase from the water leaching solution were found.

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Electron Microscopy of Human Gallstones

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065523 ◽

1971 ◽

Vol 29 ◽

pp. 296-297

Author(s):

C. Wolpers ◽

R. Blaschke

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bile Pigment ◽

X Ray Diffraction ◽

Triclinic Crystal System ◽

X Ray ◽

Follow Up Study ◽

Infra Red ◽

Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

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Leaching Studies of Cement-Glass Package Containing Sodium Borate

MRS Proceedings ◽

10.1557/proc-84-393 ◽

1986 ◽

Vol 84 ◽

Cited By ~ 3

Author(s):

Masahiro Okamoto ◽

Koichi Chino ◽

Tsutomu Baba ◽

Tatsuo Izumida ◽

Fumio Kawamura ◽

...

Keyword(s):

Sodium Silicate ◽

Liquid Waste ◽

Sodium Borate ◽

Pressurized Water Reactor ◽

X Ray Diffraction ◽

Adsorption Ability ◽

Pressurized Water ◽

X Ray ◽

Solidification Reaction ◽

Main Components

AbstractA new solidification technique using cement-glass, which is a mixture of sodium silicate, cement, additives, and initiator of the solidification reaction, was developed for sodium borate liquid waste generated from pressurized water reactor (PWR) plants. The cement-glass could solidify eight times as much sodium borate as cement could, because the solidifying reaction of the cement-glass is not hindered by borate ions.The reaction mechanism of sodium silicate and phosphoric silicate (initiator), the main components of cement-glass, was studied through X-ray diffraction and compressive strength measurements. It was found that three- dimensionally bonded silicon dioxide was produced by polymerization of the two silicates. The leaching ratio of cesium from the cement-glass package was one-tenth that of the cement one. This low value was attributed to a high cesium adsorption ability of the cement-glass and it could be theoretically predicted accordingly.

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Study on leaching kinetics of hexavalent chromium from aged calcium-free chromium slag

Main Group Chemistry ◽

10.3233/mgc-210045 ◽

2021 ◽

pp. 1-13

Author(s):

Quan Qi ◽

Liang Li ◽

Liangyu Wei ◽

Baoming Hu ◽

Zheng Liu ◽

...

Keyword(s):

Hexavalent Chromium ◽

Resource Utilization ◽

Scientific Basis ◽

Diffusion Reaction ◽

Leaching Kinetics ◽

Leaching Rate ◽

Chromium Slag ◽

Leaching Solution ◽

Main Components ◽

Kinetics Of

To provide a scientific basis for the resource utilization of chromium slag, this article studies the release law of hexavalent chromium in the aged calcium-free chromium slag. XRD (X-ray diffractometer) and MLA (Mineral Liberation Analyzer) were used to analyze the composition of the chromium slag; using sulfuric acid-nitric acid as the leaching solution, the release law of hexavalent chromium in chromium slag and the leaching kinetics were studied. The results show that main components of the chromium slag are magnesioferrite, chromite, hematite, hydrargillite, and spinel; chromium is mainly present in chromite and magnesioferrite; the leaching rate of hexavalent chromium increases with the increase of temperature or the decrease of pH. The analysis of leaching kinetics shows the leaching rate is controlled by the internal diffusion reaction, and the apparent activation energy is 11.93 kJ·mol–1. The chromium slag is aged in high temperature seasons, which is conducive to the precipitation of hexavalent chromium in the chromium slag, can increase the yield of chromate in the roasting kiln, and is conducive to resource utilization; chromium slag should be stored in order to prevent acid rain erosion which leads to environmental pollution risk (e.g. drinking water).

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Characterization and A Preliminary Study of TiO2 Synthesis from Lampung Iron Sand

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.849.113 ◽

2020 ◽

Vol 849 ◽

pp. 113-118

Author(s):

Yayat Iman Supriyatna ◽

Slamet Sumardi ◽

Widi Astuti ◽

Athessia N. Nainggolan ◽

Ajeng W. Ismail ◽

...

Keyword(s):

Food Packaging ◽

Xrd Analysis ◽

Major Elements ◽

Raw Material ◽

Solid Residue ◽

X Ray Diffraction ◽

X Ray ◽

Leaching Solution ◽

Ti Content

The purpose of this study is to characterize Lampung iron sand and to conduct preliminary experiments on the TiO2 synthesis which can be used for the manufacturing of functional food packaging. The iron sand from South Lampung Regency, Lampung Province that will be utilized as raw material. The experiment was initiated by sieving the iron sand on 80, 100, 150, 200 and 325 mesh sieves. Analysis using X-Ray Fluorescence (XRF) to determine the element content and X-Ray Diffraction (XRD) to observe the mineralization of the iron sand was conducted. The experiment was carried out through the stages of leaching, precipitation, and calcination. Roasting was applied firstly by putting the iron sand into the muffle furnace for 5 hours at a temperature of 700°C. Followed by leaching using HCl for 48 hours and heated at 105°C with a stirring speed of 300 rpm. The leaching solution was filtered with filtrate and solid residue as products. The solid residue was then leached using 10% H2O2 solution. The leached filtrate was heated at 105°C for 40 minutes resulting TiO2 precipitates (powder). Further, the powder was calcined and characterized. Characterization of raw material using XRF shows the major elements of Fe, Ti, Mg, Si, Al and Ca. The highest Ti content is found in mesh 200 with 9.6%, while iron content is about 80.7%. While from the XRD analysis, it shows five mineral types namely magnetite (Fe3O4), Rhodonite (Mn, Fe, Mg, Ca) SiO3, Quart (SiO2), Ilmenite (FeOTiO2) and Rutile (TiO2). The preliminary experiment showed that the Ti content in the synthesized TiO2 powder is 21.2%. The purity of TiO2 is low due to the presence of Fe metal which is dissolved during leaching, so that prior to precipitation purification is needed to remove impurities such as iron and other metals.

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Variation of the Chemical Composition of Waste Cooking Oils upon Bentonite Filtration

Resources ◽

10.3390/resources8020108 ◽

2019 ◽

Vol 8 (2) ◽

pp. 108 ◽

Cited By ~ 10

Author(s):

Alberto Mannu ◽

Gina Vlahopoulou ◽

Paolo Urgeghe ◽

Monica Ferro ◽

Alessandra Del Caro ◽

...

Keyword(s):

Particle Size ◽

Chemical Composition ◽

Solid Phase ◽

Volatile Fraction ◽

X Ray Diffraction ◽

Specific Chemical ◽

Waste Cooking Oils ◽

Main Components ◽

Cooking Oils ◽

Chemical Groups

The chemical composition and the color of samples of waste cooking oils (WCOs) were determined prior to and after filtration on two different pads of bentonite differing in particle size. The volatile fraction was monitored by headspace solid-phase microextraction (HS-SPME) coupled with gas-chromatography, while the variation of the composition of the main components was analyzed by 1H NMR. Both techniques allowed the detection of some decomposition products, such as polymers, terpenes, and derivatives of the Maillard process. The analysis of the chemical composition prior to and after bentonite treatment revealed a tendency for the clays to retain specific chemical groups (such as carboxylic acids or double bonds), independent of their particle size. A pair comparison test was conducted in order to detect the sensory differences of the intensity of aroma between the WCO treated with the two different bentonites. In addition, characterization of the bentonite by means of powder X-ray diffraction (XRD) and thermogravimetric measurements (TG) was performed.

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The transformation and enrichment of rare earth sulfate in Bayan Obo ore water leaching solution by dibenzyl phosphate based extraction-precipitation method

Separation and Purification Technology ◽

10.1016/j.seppur.2021.119464 ◽

2021 ◽

pp. 119464

Author(s):

Hailan Zhi ◽

Luo Feng ◽

Shuainan Ni ◽

Jianguo Cui ◽

Xiaoqi Sun

Keyword(s):

Rare Earth ◽

Precipitation Method ◽

Water Leaching ◽

Leaching Solution ◽

Bayan Obo

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Efficient Separation of Silicon and Vanadium by Sodium Roasting-Water Leaching from Vanadium Slag and CaV2O6 Preparation

Crystals ◽

10.3390/cryst11030255 ◽

2021 ◽

Vol 11 (3) ◽

pp. 255

Author(s):

Changqing Li ◽

Haichao Zhang ◽

Ma Tao ◽

Xufeng Wang ◽

Hang Li ◽

...

Keyword(s):

New Product ◽

Molar Ratio ◽

Migration Behavior ◽

Vanadium Slag ◽

Water Leaching ◽

Solid Ratio ◽

Leaching Solution ◽

Micro Morphology ◽

Precipitation Ratio ◽

Separation Behavior

Calcium vanadate (CaV2O6), a new product of vanadium precipitation, was obtained from vanadium slag by sodium roasting-water leaching and calcium precipitation. The separation behavior of vanadium and silicon in vanadium slag during sodium roasting and water leaching was systematically studied, and micro-morphology and valence migration behavior of vanadium and Fe in vanadium slag, roasting slag, and residue were revealed. The Na2CO3 was added to the vanadium slag at 20% mass fraction, roasted at 790 ℃, and kept for 120 min, the roasted sample was added to the deionized aqueous solution with a liquid-solid ratio of (L/S) 5mL/g, and then heated at 90 ℃ for 60 min, 89.54% vanadium and 1.96% chromium were extracted. Sodium carbonate tends to combine with vanadium to form sodium vanadate, while silicon is easy to combine with Fe and Na to form acmite (NaFeSi2O6). When the molar ratio of N (Ca/V) is 0.6 and CaO, is added to adjust the pH of vanadium leaching solution to 6.7 ± 0.1 and precipitate 90 min at 90 ℃, vanadium is precipitated in the form of CaV2O6 with a purity of 95.69%, under these conditions, the precipitation ratio is 95.03%.

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Double sulfates of cobalt(II), nickel(II), copper(II) and zinc(II) with trimethylammonium cation: synthesis, identification and thermal decomposition

Thermochimica Acta ◽

10.1016/0040-6031(93)80279-j ◽

1993 ◽

Vol 228 ◽

pp. 102-110

Author(s):

S. Aleksovska ◽

V. Jordanovska

Keyword(s):

Thermal Decomposition ◽

Double Sulfates

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A Facile Method to Construct MXene/CuO Nanocomposite with Enhanced Catalytic Activity of CuO on Thermal Decomposition of Ammonium Perchlorate

Materials ◽

10.3390/ma11122457 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2457 ◽

Cited By ~ 6

Author(s):

Haifeng Zhao ◽

Jing Lv ◽

Junshan Sang ◽

Li Zhu ◽

Peng Zheng ◽

...

Keyword(s):

Thermal Decomposition ◽

Catalytic Activity ◽

Ammonium Perchlorate ◽

Photoelectron Spectra ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Improved Performance ◽

Calcination Method

In this work, a mixing-calcination method was developed to facilely construct MXene/CuO nanocomposite. CuO and MXene were first dispersed in ethanol with sufficient mixing. After solvent evaporation, the dried mixture was calcinated under argon to produce a MXene/CuO nanocomposite. As characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and X-ray photoelectron spectra (XPS), CuO nanoparticles (60–100 nm) were uniformly distributed on the surface and edge of MXene nanosheets. Furthermore, as evaluated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), the high-temperature decomposition (HTD) temperature decrease of ammonium perchlorate (AP) upon addition of 1 wt% CuO (hybridized with 1 wt% MXene) was comparable with that of 2 wt% CuO alone, suggesting an enhanced catalytic activity of CuO on thermal decomposition of AP upon hybridization with MXene nanosheets. This strategy could be further applied to construct other MXene/transition metal oxide (MXene/TMO) composites with improved performance for various applications.

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Alkali Fusion-Leaching Method For Comprehensive Processing Of Fly Ash

KnE Materials Science ◽

10.18502/kms.v2i2.952 ◽

2017 ◽

Vol 2 (2) ◽

pp. 89 ◽

Cited By ~ 3

Author(s):

A.A. Shoppert ◽

I.V. Loginova ◽

L.I. Chaikin ◽

D.A. Rogozhnikov

Keyword(s):

Fly Ash ◽

Power Plant ◽

X Ray Diffraction ◽

Water Leaching ◽

X Ray ◽

Comprehensive Utilization ◽

Alkali Fusion ◽

Wet Chemical ◽

Promising Source ◽

Comprehensive Processing

Fly ash, composed of mullite, hematite, amorphous silica and quartz, is a promising source for the recovery of alumina and silica. Desilication with help of NaOH and alkali fusion-leaching method and utilization of alumina and silica in the fly ash for preparation of sodalite and silica white were explored in this research. The samples were characterized by using wet chemical analysis and X-ray diffraction. The optimal extraction of SiO2 from Reftinskaya power plant fly ash was 46.2% with leaching at 95 oC for 3 h. Sodalite was synthesized at 200 °C for 1 h followed water leaching at 95 °C for 1 h. Silica white with specific surface area 180-220 m2/g was prepared by carbonation of the Na2SiO3 solution at 40 oC for 90-120 min. The as-prepared silica has a purity of 98,8%.The proposed method is suitable for the comprehensive utilization of the fly ash.

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