Enhanced Removal of Pb from Electrolytic Manganese Anode Slime by Vacuum Carbothermal Reduction

Abstract Electrolytic manganese anode slime (EMAS) is produced during the production of electrolytic manganese metal. In this study, a method based on vacuum carbothermal reduction was used for Pb removal in EMAS. A Pb-removal efficiency of 99.85% and MnO purity in EMAS of 97.34 wt.% was obtained for a reduction temperature of 950°C and a carbon mass ratio of 10% for a holding time of 100 min. The dense structure of the EMAS was destroyed, a large number of multidimensional pores and cracks were formed, and the Pd-containing compound was reduced to elemental Pb by the vacuum carbothermal reduction. A recovery efficiency for chemical MnO2 of 36.6% was obtained via preparation from Pd-removed EMAS through the “roasting-pickling disproportionation” process, with an acid washing time of 100 min, acid washing temperature of 70°C, H2SO4 concentration of 0.8 mol/L, liquid-solid mass ratio of 7 mL/g, calcination temperature of 60°C and calcination time of 2.5 h. Moreover, the crystal form of the prepared chemical MnO2 was found to be basically the same as that of electrolytic MnO2, and its specific surface area, micropore volume and discharge capacity were all higher than that of electrolytic MnO2. This study provides a new method for Pd removal and recycling for EMAS.

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Fabrication of titanium carbide reinforced iron matrix cermet by vacuum carbothermal reduction of ilmenite

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq171114015w ◽

2019 ◽

Vol 25 (1) ◽

pp. 21-29

Author(s):

Ke-Han Wu ◽

Hai-Peng Gou ◽

Guo-Hua Zhang ◽

Kuo-Chih Chou

Keyword(s):

Carbothermal Reduction ◽

Bending Strength ◽

Raw Materials ◽

Energy Dispersive Spectrometer ◽

Mass Ratio ◽

X Ray Diffraction ◽

Iron Matrix ◽

Vacuum Sintering ◽

Electron Probe Micro Analyzer ◽

Carbon Mass

Iron matrix cermet reinforced with TiC has been produced by vacuum carbothermal reduction of ilmenite followed by sintering processes. The influences of reduction temperature and carbon mass ratio were discussed in detail. X-Ray diffraction (XRD), electron probe micro-analyzer (EPMA) and scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) were employed to characterize the phase composition and microstructures. After carbothermic reduction, most of Mg, Mn, Ca evaporated from the sample; Si and part of Al was dissolved in the iron matrix. The obtained powders were used as the raw materials to produce TiC-Fe cermet by vacuum sintering. Density, hardness and bending strength of the samples were examined. The optimal cermet products after heat treatment had a density of 5.38 g?cm-1, a hardness of 1125.5 HV and a bending strength of 667 MPa, which was obtained at the carbon/ilmenite mass ratio of 0.378:1 at 1773 K under the pressure of 10 Pa.

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Hydroxylation of electrolytic manganese anode slime with EDTA-2Na and its adsorption of methylene blue

Separation and Purification Technology ◽

10.1016/j.seppur.2021.119526 ◽

2021 ◽

pp. 119526

Author(s):

Pengxin Su ◽

Qiuyue Wan ◽

Yong Yang ◽

Jiancheng Shu ◽

Hongyuan Zhao ◽

...

Keyword(s):

Methylene Blue ◽

Anode Slime ◽

Electrolytic Manganese

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Study on the Preparation and Amplification Experiment of Al-Pillared Montmorillonite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1440 ◽

2011 ◽

Vol 396-398 ◽

pp. 1440-1445

Author(s):

Gang Chen ◽

Chun Jie Yan ◽

Jin Feng Shou ◽

Juan Mei ◽

Nan Nan Chen

Keyword(s):

Pilot Scale ◽

Micropore Volume ◽

Bet Surface Area ◽

Scale Production ◽

Mass Ratio ◽

Optimum Conditions ◽

Technical Parameters ◽

Pillared Montmorillonite ◽

Commercial Aluminium ◽

Major Factors

A method of preparation and pilot scale production of Al-pillared montmorillonite has been developed. There is a minimum of time and amount of liquid. And it is simpler to operate than the conventional method of pillaring by using the commercial aluminium hydroxychloride(PAC) powder as the pillaring agent. Here, the effect of the major factors such as the mass ratio of PAC to montmorillonite, the concentration of montmorillonite slurry, the sodium agent pretreatment, washing times and drying temperature on the Al-pillared montmorillonite are studied. Then the optimal technical parameters is determined. XRD, BET surface area and micropore volume are applied in order to study the structure and properties of Al-pillared montmorillonite. As a result, the amplification experiment under the optimum conditions shows that this method offers the potential for extension to an industrial-scale process.

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Synthesis of Zeolite from Carbothermal Reduction Electrolytic Manganese Residue for the Removal of Macrolide Antibiotics from Aqueous Solution

Materials ◽

10.3390/ma11112133 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2133 ◽

Cited By ~ 1

Author(s):

Xuli Li ◽

Yue Zeng ◽

Fangyuan Chen ◽

Teng Wang ◽

Yixin Li ◽

...

Keyword(s):

Aqueous Solution ◽

Carbothermal Reduction ◽

Adsorption Process ◽

Hydroxyl Group ◽

Macrolide Antibiotics ◽

Adsorption Sites ◽

Electrolytic Manganese ◽

Electrolytic Manganese Residue ◽

Pseudo Second Order ◽

The Fourier Transform

Zeolite analcime (EMANA) was synthesized through the hydrothermal method by using carbothermal reduction electrolytic manganese residue (CR-EMR). The structural properties of EMANA and CR-EMR were studied using various characterization techniques. After hydrothermal synthesis, the CR-EMR became super-microporous, and the surface area increased by 4.76 times than before. Among the various synthesized zeolites, 6 h-synthesized EMANA was selected as the best adsorbent for macrolide antibiotics in aqueous solution. The adsorption performance of EMANA on the adsorption capacity was examined by using various experimental parameters, such as contact time (0–24 h), initial concentration (50–300 mg/L), temperature (30–50 °C) and pH (3–13). The experimental results were also analyzed by the Langmuir and Freundlich adsorption models, with the latter obtaining better representation. The adsorption process could be described well by the pseudo-second-order model, even under a low concentration (50 mg/L). This result suggests that the adsorption process of macrolide antibiotics is due to chemisorption. According to the Fourier Transform infrared spectroscopy (FT-IR) results, the adsorption of zeolite was mainly due to its hydroxyl group, which played an important role during the adsorption process. Moreover, EMANA is more suitable for treatment of roxithromycin (ROX) than azithromycin (AZM), because ROX has more adsorption sites for the hydroxyl group.

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Preparation, Characterization and Hemostatic Properties of Chitosan Caffeates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.814.365 ◽

2019 ◽

Vol 814 ◽

pp. 365-371

Author(s):

Si Tong Lu ◽

Dong Ying Zhang ◽

Zhang Hu ◽

Si Dong Li ◽

Pu Wang Li

Keyword(s):

Caffeic Acid ◽

Freeze Drying ◽

Water Solubility ◽

Crystal Form ◽

Positive Control ◽

Mass Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Yunnan Baiyao ◽

Better Than

In this paper, chitosan and caffeic acid were used as starting materials to prepare chitosan caffeates by reflux-heating and freeze-drying. The structures of chitosan caffeates were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and potentiometric titration. At the same time, the physical properties of chitosan caffeates were tested and the hemostatic properties were evaluated. The results showed that four chitosan caffeates with different mass ratios of chitosan and caffeic acid (1:1, 1:2, 1:4, 1:6) had been successfully prepared, which enhanced the water solubility. FTIR analysis demonstrated that caffeic acid had been successfully grafted onto chitosan chains. XRD showed that the crystal form of chitosan changed to some extent and the chain had some regularity in some directions, but its crystallinity reduced. Chitosan caffeates, particularly mass ratio of 1:1, showed excellent hemostatic properties and even better than chitosan and the positive control (Yunnan Baiyao), which were expected to be developed as an effective biomaterial for hemostasis.

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An Influence of EAF Dust Calcining Conditions on Zinc Leaching Efficiency in Ammonium-Chloride Media

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.299.963 ◽

2020 ◽

Vol 299 ◽

pp. 963-967

Author(s):

Yulia I. Toporkova ◽

D.A. Prodanova ◽

O.S. Anisimova

Keyword(s):

Extraction Efficiency ◽

Electric Arc ◽

Arc Furnace ◽

Optimal Conditions ◽

Mass Ratio ◽

Zinc Extraction ◽

Calcination Time ◽

Eaf Dust ◽

Two Stages ◽

Leaching Efficiency

An ammonium leaching of electric arc furnace dust (EAFD) was described in this paper. Ural steelmaking plants obtain EAFD of the following chemical composition, %: 23 Zn; 26 Fe; 10 Cl; 2,5 Ca; 2 Mg; 1,2 Pb; 1 Na. The most complete zinc extraction can be achieved with two-stages treatment by calcination of dusts [1], followed by leaching. The effect of calcination temperature (500-1000 °C), calcination time (1-4 hours) and Ca/Fe mass ratio on zinc extraction efficiency in ammonia solutions was studied. The optimal conditions were proposed to extract up to 87% zinc.

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Clay-organic complexes in a Polish loess soil

International Agrophysics ◽

10.1515/intag-2016-0054 ◽

2017 ◽

Vol 31 (3) ◽

pp. 447-452 ◽

Cited By ~ 1

Author(s):

Ewa A. Czyż ◽

Jerzy Rejman ◽

Anthony R. Dexter ◽

Jan Jadczyszyn ◽

Anna Rafalska-Przysucha ◽

...

Keyword(s):

Loess Soil ◽

Soil Samples ◽

Mass Ratio ◽

Loessial Soil ◽

Soil Physical Quality ◽

Organic Complexes ◽

Carbon Mass ◽

Predicted Values ◽

Strip Tillage ◽

Range Of Values

AbstractComplexes formed between clay and soil organic matter are important for carbon sequestration and for soil physical quality. Here, we use samples of loessial soil from South-East Poland to explore the phenomenon of complexing in loess. Soil samples were collected from a single catchment 8 years after the introduction of strip tillage and their compositions were characterized by traditional methods. Complexing was characterized in terms of the content of non-complexed clay which was estimated in two ways: firstly, by measurement of the content of readily-dispersible clay (which was assumed to be the non-complexed clay); and secondly, by calculation using algorithms that had been developed and evaluated previously. The calculations were based on the concept that, at carbon saturation, the clay/organic carbon mass ratio is equal ton. The calculations were done with a range of values ofn. It was assumed that the correct value ofnwas that which gave the greatest coefficient of correlation between the measured values of clay dispersion and the predicted values of non-complexed clay. For the loess used, the optimum value wasn= 14.

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Synthesis and characterization of mesoporous carbon spheres

Materials Science-Poland ◽

10.2478/msp-2019-0069 ◽

2019 ◽

Vol 37 (4) ◽

pp. 585-589

Author(s):

Shuiping Li ◽

Huajun Zhu ◽

Guilong Xu ◽

Qing Lin ◽

Chengshuang Wang ◽

...

Keyword(s):

Mesoporous Carbon ◽

Cost Effective ◽

Crystal Form ◽

Carbon Sphere ◽

Selective Leaching ◽

Mass Ratio ◽

Step Method ◽

Resorcinol Formaldehyde ◽

Structure Morphology

AbstractA three-step method was used for the synthesis of mesoporous carbon sphere (MCS) material: firstly, silica (SiO2) nanoparticles were synthesized by the modified Stöber procedure; secondly, tetraethyl orthosilicate (TEOS) and cetyltrimethylammonium chloride (CTAC) were grafted onto SiO2 core nanoparticles to prepare SiO2@SiO2-CTAC hard templates; lastly, MCS material was fabricated by carbonizing and selective leaching SiO2/resorcinol-formaldehyde (RF) composites. The influence of the mass ratio of R-F/silica on the structure, morphology and crystal form was studied. The results indicate that the MCS materials have a uniform morphology. The increase of the mass ratio of R-F/silica can increase the specific surface area and pore volume. The three-step method provides a cost-effective procedure for the fabrication of MCS materials with uniform morphology.

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