Effect of NaCN:ZnSO4 Mixture Molar Ratio and Particle-Size Distribution on Pb-Zn and Fe Selective Separation by Froth Flotation

A large amount of carbon dust is generated in the process of aluminum smelting by molten salt electrolysis. The carbon dust is solid hazardous waste but contains a large quantity of recyclable components such as carbon and fluoride. How to recycle carbon dust more effectively is a challenge in the aluminum electrolysis field. In this study, X-ray diffraction, scanning electron microscope, and other methods were used to analyze the phase composition of electrolytic aluminum carbon dust. The effects of particle size distribution of carbon dust, impeller speed, reagent addition, mixing time, and flotation time on the flotation recovery of carbon dust were studied. The optimal flotation conditions were obtained and the flotation products were analyzed. The results show that the optimal particle size distribution is 70% of particles below 200 mesh, corresponding to a grinding time of 11 min. The optimum speed of the flotation machine was to be between 1600 and 1800 r/min with the best slurry concentration of 20–30% and 5 min mixing time, and the collector kerosene was suitable for adding in batches. Under the above conditions, the recovered carbon powder with a carbon content of 75.6% was obtained, and the carbon recovery rate was 86.9%.

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Preparation of Potassium Niobate/Barium Titanate Nanocomposite Ceramics with a Wide Barium Titanate Particle Size Distribution and their Dielectric Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.582.76 ◽

2013 ◽

Vol 582 ◽

pp. 76-79

Author(s):

Ichiro Fujii ◽

Kenta Yamashita ◽

Kouichi Nakashima ◽

Yoshinori Fujikawa ◽

Daisuke Tanaka ◽

...

Keyword(s):

Crystal Structure ◽

Particle Size ◽

Barium Titanate ◽

Particle Size Distribution ◽

Size Distribution ◽

Molar Ratio ◽

Narrow Particle Size Distribution ◽

Potassium Niobate ◽

Barium Titanate Powder ◽

Wide Particle Size Distribution

Denser, solvothermally synthesized KNbO3 (KN) / BaTiO3 (BT) composites with heteroepitaxial interfaces were prepared using the barium titanate powder with a wide particle size distribution. The relative density was 68 - 80 %, which was larger than that of the composites prepared using the barium titanate powder with a narrow particle size distribution. The dielectric constant was 300 450 and it was maximized at the KN/BT molar ratio of 0.5. The origin was discussed with the microstructure and crystal structure.

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EFFECT OF REVERSE MICELLE WATER POOL IN SYNTHESIS OF ZIRCONIA STABILIZED COPPER NANOCOMPOSITE

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512002474 ◽

2012 ◽

Vol 05 ◽

pp. 559-567

Author(s):

H. Abdizadeh ◽

Y. Vahidshad ◽

H. R. Baharvandi ◽

M. Akbari Baseri

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Physical Properties ◽

Size Distribution ◽

Anionic Surfactant ◽

Reverse Micelle ◽

Sol Gel ◽

Molar Ratio ◽

Water Pool ◽

20 Nm

In the water-in-oil (W/O) microemulsions based on anionic (AOT) surfactants, the ω value (molar ratio of water to surfactant), precursor, and surfactant could remarkably affect the synthesis of CuO - ZrO 2 nanocomposite and the morphologies of the sol-gel products simultaneously. In this study, CuO - ZrO 2 nanoparticles are synthesized using microreactors made of surfactant/water/n-hexane microemulsions and discusses the effect of different microemulsion variables on the particle size and particle size distribution by water-to-surfactant molar ratio. The obtained powders are characterized by DTA, XRD, SEM, EDS, and TEM and their physical properties are compared. For AOT surfactant the particle size increased with increasing the water to surfactant molar ratio. The particles size of CuO - ZrO 2 nanocomposite in sample with anionic surfactant with molar ratio of 6 that calcined at 600°C is between 15-20 nm.

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The Influence of the Peptide Molar Ratios on the Functionalization of Gold Nanoparticles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.872.94 ◽

2013 ◽

Vol 872 ◽

pp. 94-105

Author(s):

Mayra C. Ramirez-Camacho ◽

Inga Tuzovskaya ◽

Nina Bogdanchikova ◽

Alexey Pestryakov ◽

Arturo Susarrey-Arce ◽

...

Keyword(s):

Particle Size ◽

Gold Nanoparticles ◽

Particle Size Distribution ◽

Size Distribution ◽

Sodium Citrate ◽

Red Shift ◽

Molar Ratio ◽

Narrow Particle Size Distribution ◽

Plasmon Peak ◽

Vis Spectroscopy

Au nanoparticles (NPs) functionalized with L-cysteine (Cys) and cysteine-glycine (Cys-Gly) were synthetized. The AuNPs were prepared using sodium citrate as reducing agent. The influence of the molar concentrations of Cys and Cys-Gly, as well as the sodium citrate is studied on particle size and particle size distribution. TEM measurements revealed the formation of AuNPs with diameter in the range 5-35 nm which corresponds to nontoxic sizes [we should add a reference here, perhaps number one]. The optimal particle size for biomedical application along with narrow particle size distribution was observed for samples prepared with molar ratio of CAu:Ccitrate = 1:10. The results of UV-Vis spectroscopy revealed the interaction of the AuNPs with Cys and Gly-Cys demonstrated by a visible change in the absorption intensities of the plasmon peak located at 520 nm after AuNP functionalization and a slight shifting of this gold nanoparticles plasmon peak. Thus, any dielectric shell on surface of particles with more refraction index (and, correspondingly, dielectric function) can produce the particles with the red shift. Such effect of the surface shell with red-shift in the range of few nanometers observed for the AuNPs functionalized with Cys and Cys-Gly (Fig. 4) can be interpreted as thin or discontinuous layer of aminoacid molecules according to the data of optical spectra simulation.

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Sol-Gel Synthesis of Amorphous Silica Nanoparticles: Study of the Process Parameters Influence on Structure and Particle Size Distribution

Materials Science Forum ◽

10.4028/www.scientific.net/msf.912.77 ◽

2018 ◽

Vol 912 ◽

pp. 77-81

Author(s):

Renata Deliberato Aspasio ◽

Jairo Freitas da Silva Jr. ◽

Roger Borges ◽

Juliana Marchi

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Silica Nanoparticles ◽

Size Distribution ◽

Functional Groups ◽

Process Parameters ◽

Amorphous Silica ◽

Sol Gel ◽

Molar Ratio ◽

Sol Gel Synthesis

The synthesis of silica particles at the nanoscale through the sol-gel method is of great interest due to their potential use in industrial applications. The Stöber method is the most used method for the silica nanoparticles production using ammonia as a catalyst. This work studied the sol-gel synthesis of amorphous silica nanoparticles described by Stöber, in order to evaluate the influence of the variation of the process parameters (molar ratio water/TEOS = 25 and 55, reagent feed rate = 0.6 mL/min and 18 mL/min, pH = 12 and 9 and reaction time of 0, 5, 30, 60 and 120 minutes) on the particle size distribution and structural functional groups. The particle size distribution was analyzed by dynamic light scattering (DLS) and the structural functional groups was analyzed by infrared spectroscopy through Fourier transform (FTIR). The molar ratio water/TEOS influenced the functional groups presents and the time influenced the particle diameter distribution. It was not possible to identify the influence of the feed rate and pH in the results. The particle diameters found were between 200-500nm. This result may be occurred due to mass diffusion and/or nanoparticles aggregation.

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