Recovery of Molybdenum and Rhenium Using Selective Precipitation Method from Molybdenite Roasting Dust in Alkali Leaching Solution

AbstractIn order to extract molybdenum (Mo) from alkali leaching solution of low-grade Mo concentrate, static and dynamic ion exchange experiments were performed. The static experiments results indicated that the adsorption capacity of D201 resins reached 93.50% at pH 3.5, while the adsorption capacity of D314 resins was 95.47%. Therefore, D314 resin was adopted for further experiments. The dynamic experiments results indicated that the adsorption capacity of Mo reached 96.77% when the flow rate of leaching solution was 1 ml/min. The loaded resin could be desorbed by 10% ammonia solution. In consequence, the maximum concentration of Mo in eluate was 122 g/l. In the precipitation process, the Mo recovery reached 97.81%, and the obtained Mo oxide products met the requirement of YMo 55 national standard in GB/T24482-2009 and Grade A standard of ASTM A146-04 (2014).

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Immobilization of Cr(VI) in Soil Using a Montmorillonite-Supported Carboxymethyl Cellulose-Stabilized Iron Sulfide Composite: Effectiveness and Biotoxicity Assessment

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17176087 ◽

2020 ◽

Vol 17 (17) ◽

pp. 6087

Author(s):

Dading Zhang ◽

Yanqiu Xu ◽

Xiaofei Li ◽

Zhenhai Liu ◽

Lina Wang ◽

...

Keyword(s):

Soil Remediation ◽

Contaminated Soil ◽

Photoelectron Spectroscopy ◽

Carboxymethyl Cellulose ◽

Iron Sulfide ◽

Soil Mass ◽

Precipitation Method ◽

Removal Capacity ◽

Leaching Solution ◽

Co Precipitation

A novel composite of montmorillonite-supported carboxymethyl cellulose-stabilized nanoscale iron sulfide (CMC@MMT-FeS), prepared using the co-precipitation method, was applied to remediate hexavalent chromium (Cr(VI))-contaminated soil. Cr(VI)-removal capacity increased with increasing FeS-particle loading. We tested the efficacy of CMC@MMT-FeS at three concentrations of FeS: 0.2, 0.5, and 1 mmol/g, hereafter referred to as 0.2 CMC@MMT-FeS, 0.5 CMC@MMT-FeS, and 1.0 CMC@MMT-FeS, respectively. The soil Cr(VI) concentration decreased by 90.7% (from an initial concentration of 424.6 to 39.4 mg/kg) after 30 days, following addition of 5% (composite–soil mass proportion) 1.0 CMC@MMT-FeS. When 2% 0.5 CMC@MMT-FeS was added to Cr(VI)-contaminated soil, the Cr(VI) removal efficiency, as measured in the leaching solution using the toxicity characteristic leaching procedure, was 90.3%, meeting the environmental protection standard for hazardous waste (5 mg/kg). The European Community Bureau of Reference (BCR) test confirmed that the main Cr fractions in the soil samples changed from acid-exchangeable fractions to oxidable fractions and residual fractions after 30 days of soil remediation by the composite. Moreover, the main complex formed during remediation was Fe(III)–Cr(III), based on BCR and X-ray photoelectron spectroscopy analyses. Biotoxicity of the remediated soils, using Vicia faba and Eisenia foetida, was analyzed and evaluated. Our results indicate that CMC@MMT-FeS effectively immobilizes Cr(VI), with widespread potential application in Cr(VI)-contaminated soil remediation.

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Synthesis of Magnesium Aluminate Spinel Powder from the Purified Sodium Hydroxide Leaching Solution of Black Dross

Processes ◽

10.3390/pr7100741 ◽

2019 ◽

Vol 7 (10) ◽

pp. 741 ◽

Cited By ~ 1

Author(s):

Nguyen ◽

Lee

Keyword(s):

Sodium Hydroxide ◽

Ball Milling ◽

Calcination Temperature ◽

Precipitation Method ◽

Magnesium Aluminate ◽

Magnesium Aluminate Spinel ◽

Complete Conversion ◽

Milling Method ◽

Leaching Solution ◽

Co Precipitation

Synthesis of magnesium aluminate spinel (MgAl2O4) was investigated by employing ball milling and co-precipitation methods. The starting materials (aluminum hydroxides) were obtained from the purified sodium hydroxide leaching solution of black dross. The characteristics of the synthesized spinel was analyzed through X-ray diffraction (XRD), scanning electron microscopy (SEM) images. In this work, the effect of calcination temperature and time on the formation of spinel by the two methods was compared. Calcination temperature showed a great effect on the formation of spinel in both methods. The results showed that the co-precipitation method has many advantages over the ball milling method. In ball milling method, complete conversion of the starting materials to spinel was impossible even at 1500 °C, while complete conversion to spinel was accomplished at 1000 °C for 5 h by the co-precipitation method. The average size of the spinel synthesized at these optimum conditions of the co-precipitation method was about 17 nm. A process can be developed to synthesize spinel from the black dross which is regarded as hazardous materials.

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Studies on uranium recovery from a U-bearing Radoniów Dump

Nukleonika ◽

10.2478/nuka-2021-0017 ◽

2021 ◽

Vol 66 (4) ◽

pp. 115-119

Author(s):

Katarzyna Kiegiel ◽

Otton Roubinek ◽

Dorota Gajda ◽

Paweł Kalbarczyk ◽

Grażyna Zakrzewska-Kołtuniewicz ◽

...

Keyword(s):

Uranium Concentration ◽

Precipitation Method ◽

Mechanical Mixing ◽

Uranium Recovery ◽

Uranium Ions ◽

Work Volume ◽

Uranium Bioleaching ◽

Leaching Solution ◽

Two Stages ◽

Dump Leaching

Abstract This work reports the possibility of uranium recovery from a post-mining uranium ore dump in Poland by a bioleaching method. The studies were conducted on the dump leaching model with the mass of 570 kg of uranium bearing mineral material from Radoniów pile and in the periodic bioreactor with a work volume of 80 dm3 and with mechanical mixing and aeration of the charge. The uranium concentration in the examined material was about 800 ppm. In this process, the consortium of microorganisms isolated from former mines was used. It was composed of the following microorganisms: Bacillius, Pseudomonas, Sphingomonas, Thiobacillus, Halothiobacillus, Thiomonas, and Geothrix. The efficiency of the uranium bioleaching process was 98% in the reactor, and a yield of 70% was obtained in the dump leaching model. The post-leaching solution contained significant amounts of uranium ions that were separated in two stages: (1) by ion chromatography and then (2) by a two-step precipitation method. The resulting solution was a source of ammonium diuranate, the precursor of yellowcake (uranium oxides).

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Distribution of thiobarbituric acid-reactive substances in lipoproteins and proteins in serum.

Clinical Chemistry ◽

10.1093/clinchem/35.10.2054 ◽

1989 ◽

Vol 35 (10) ◽

pp. 2054-2058 ◽

Cited By ~ 16

Author(s):

D Bonnefont ◽

A Legrand ◽

J Peynet ◽

J Emerit ◽

J Delattre ◽

...

Keyword(s):

Apolipoprotein B ◽

Thiobarbituric Acid ◽

Precipitation Method ◽

High Density Lipoproteins ◽

Separation Procedure ◽

Serum Lipoproteins ◽

Thiobarbituric Acid Reactive Substances ◽

Selective Precipitation ◽

Acid Reaction

Abstract We assessed the distribution of malondialdehyde (MDA) in lipoproteins and proteins in serum after using two procedures to separate the lipoproteins: sequential ultracentrifugation or selective precipitation with a sodium phosphotungstate and magnesium chloride reagent followed by ultracentrifugation of the supernate. MDA concentrations were determined by the thiobarbituric acid reaction and quantified by fluorometry. We found that 43% of the thiobarbituric acid-reactive substances (TBARS) was bound to the lipoproteins--27% to very-low- and low-density lipoproteins (VLDL-LDL) and 16% to high-density lipoproteins (HDL)--and from 11.5% to 15.8% to proteins, depending on the separation procedure. Residual unbound TBARS were located in the ultracentrifugation layers that contained no lipoproteins or proteins. The TBARS concentration in serum lipoproteins containing apolipoprotein B (i.e., VLDL-LDL) was the same after ultracentrifugation or selective precipitation. We therefore consider the precipitation method more suitable for routine TBARS determination in these lipoproteins, because it is easier to handle and faster. However, for determination of TBARS in HDL, selective precipitation requires subsequent ultracentrifugation at a density of 1.21 kg/L.

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REGENERATION OF ALKALI LEACHING SOLUTION THROUGH PHOSPHATE PRECIPITATION USING CALCIUM HYDROXIDE

10.37099/mtu.dc.etdr/770 ◽

2018 ◽

Author(s):

Rick Machiela

Keyword(s):

Calcium Hydroxide ◽

Alkali Leaching ◽

Leaching Solution

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Improved Purification of p55 Protein from Secreted Virus-Like Particles from Baculovirus-Infected Insect Cells by Using an Alternative Selective Precipitation Method

BioProcessing Journal ◽

10.12665/j41.cox ◽

2005 ◽

Vol 4 (1) ◽

pp. 27-29

Author(s):

Manon Cox ◽

Rick Chubet

Keyword(s):

Insect Cells ◽

Precipitation Method ◽

Selective Precipitation ◽

Virus Like Particles ◽

Infected Insect

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Treatment of Waste Cutting Oil Emulsions by Leaching Solutions of White Mud

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.1570 ◽

2011 ◽

Vol 356-360 ◽

pp. 1570-1574

Author(s):

Tao Wu ◽

De Jun Sun ◽

Yu Jiang Li ◽

Guo Chen Zhang

Keyword(s):

Low Cost ◽

High Specific Surface Area ◽

Precipitation Method ◽

Oil Emulsion ◽

Excess Surface ◽

Alkaline Conditions ◽

Leaching Solution ◽

Oil Emulsions ◽

White Mud ◽

Maximum Removal

A leaching solution of white mud was prepared from this waste material of soda production, and used for treatment of waste cutting oil emulsion. In alkaline conditions, the leaching solution of white mud generates hydroxide precipitates, which have relatively high specific surface area and excess surface energy, and readily adsorb the pollutants in waste cutting oil emulsion. The chemical composition of the white mud was determined and the hydroxide precipitates were characterized. The maximum removal efficiency (of turbidity, oil contents and TOC) was obtained at an adsorbent dosage of 4.0 g/L, pH 12.0 and 25°C. Leaching solutions of white mud could be used as an effective and low-cost material for treatment of waste cutting oil emulsion by the precipitation method.

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A rapid, high yield size-selective precipitation method for generating Au nanoparticles in organic solvents with tunably monodisperse size distributions and replaceable ligands

RSC Advances ◽

10.1039/c7ra11177k ◽

2017 ◽

Vol 7 (88) ◽

pp. 55830-55834 ◽

Cited By ~ 1

Author(s):

Steven Gravelsins ◽

Al-Amin Dhirani

Keyword(s):

Organic Solvents ◽

Au Nanoparticles ◽

Precipitation Method ◽

High Yield ◽

Size Distributions ◽

Selective Precipitation ◽

Precipitation Procedure

A fast and robust size-selective precipitation procedure by non-solvent addition has been developed to fractionalize hydrophobic-ligated Au nanoparticles with tunable sizes and monodispersities.

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