Dodecane Decomposition in a Radio-Frequency (RF) Plasma Reactor

2005 ◽  
Vol 3 (1) ◽  
Author(s):  
Laura Merlo-Sosa ◽  
Gervais Soucy
Keyword(s):  
Carbon Black ◽  
Plasma Reactor ◽  
Average Particle Size ◽  
Plasma Temperature ◽  
Experimental Results ◽  
Rf Plasma ◽  
Average Particle ◽  
Statistical Experimental Design ◽  
Operational Conditions ◽  
Carbon Molecules

The research outlined here includes a study of the production of carbon black (CB) in an inductive plasma reactor, using dodecane (C12H26) as the starting material. Thermodynamic and kinetic studies were carried out to predict the species concentrations likely to be obtained in the pyrolysis process at plasma temperatures. A thorough statistical experimental design was undertaken to investigate the influence of the different operational conditions such as: the feed rates of dodecane, the reactor pressure, the plate power applied to the plasma torch and the composition of the plasma gas, on the production of carbon black and gaseous acetylene-like compounds. Thermodynamic and kinetic models were compared with experimental results, a kinetic reaction model best representing the experimental results. Morphological analysis of the solid product using Transmission Electron Microscopy (TEM) indicates that a high plasma temperature is the most important factor affecting the final morphology of the carbon black formed during the reaction. Carbon black with average particle size of 10-30 nm and specific surface of 130 m2/g was obtained. Morphological analyses also demonstrated the presence of new structures ranging from carbon black to fullerenes and including certain “graphitized” carbon molecules.

ER Properties of a Suspension of Polymer Graft Carbon Black Particles

1999 ◽  
Vol 13 (14n16) ◽  
pp. 1682-1688
Author(s):  
Masayoshi Konishi ◽  
Teruhisa Nagashima ◽  
Yoshinobu Asako
Keyword(s):  
Shear Stress ◽  
Carbon Black ◽  
Electric Field ◽  
Silicone Oil ◽  
Average Particle Size ◽  
Average Particle ◽  
Zero Field ◽  
Average Value ◽  
Time Period ◽  
Micron Size

We newly developed ER particles with sub-micron size. The particle was polymer graft carbon black (GCB1) composed of carbon black particles and a polymer. The average particle size of GCB1 was found to be 81 nm. An ER suspension (ER1) was obtained by mixing GCB1 (30 wt%) with silicone oil (70 wt%). The ER1 showed excellent dispersion stability. Further, GCB1 particles did not settle under centrifuging at 9000G. The zero-field viscosity was 80 mPa·s at 25°C. The kinetic friction coefficient of ER1 was 0.15, while that of the silicone oil used was 0.23. When the electric field of 3 kV/mm (AC 1000 Hz) at the temperature of 25°C and the shear rate of 700 s -1 was applied to ER1, the shear stress of 116Pa was induced. The induced shear stress did not change for a long period of time period. In the temperature range between 25 and 150°C the induced shear stress and the current density were almost constant at any electric field. When 3 kV/mm (AC 50Hz) at 25°C and 700s-1 was applied to ER1, the shear stress of 88Pa was induced but the deviation of the induced shear stress from the average value was pluses and minuses 3 Pa.

scholarly journals The effect of gamma radiation on the ageing of sulfur cured NR/CSM and NBR/CSM rubber blends reinforced by carbon black

2009 ◽  
Vol 15 (4) ◽  
pp. 291-298 ◽  
Author(s):  
Gordana Markovic ◽  
Milena Marinovic-Cincovic ◽  
Vojislav Jovanovic ◽  
Suzana Samardzija-Jovanovic ◽  
Jaroslava Budinski-Simendic
Keyword(s):  
Carbon Black ◽  
Average Particle Size ◽  
Accelerated Ageing ◽  
Average Particle ◽  
Aromatic Rings ◽  
Rubber Blends ◽  
Rubber Blend ◽  
Infrared Measurements ◽  
Elastomeric Materials ◽  
Elastomeric Composites

In this work the effect of the ?-radiation dose on ageing of carbon black reinforced elastomeric materials was studied. The compounds based on natural rubber/chlorosulfonated rubber blend (NR/CSM) and butadiene acrylonitrile rubber/chlorosulfonated rubber blend (NBR/CSM) (50:50, w/w) with different loadings (0, 20, 40, 50, 60, 80 and 100 phr) of the filler with the average particle size of 40 nm were cured by sulfur. The obtained elastomeric composites were subjected to radiation doses (100, 200, 300 and 400 kGy) in the presence of oxygen. The changes of material mechanical properties were estimated after radiation accelerated ageing. By using Fourier transform infrared measurements (ATR-FTIR) it was assessed that after exposure to doses of 100 kGy alcohols, ethers, lactones, anhydrides, esters and carboxylic acids are formed in materials. The formation of shorter polyene sequences and aromatic rings in aged samples are assumed on the basis of the obtained spectra.

Controlled Growth of Silicon Particles via Plasma Pulsing and their Application as Battery Material

2021 ◽  
Author(s):  
Joseph Schwan ◽  
Brandon Wagner ◽  
Minseok Kim ◽  
Lorenzo Mangolini
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
Critical Size ◽  
Coulombic Efficiency ◽  
Plasma Reactor ◽  
Average Particle Size ◽  
Lithium Ion ◽  
Stable Operation ◽  
Average Particle ◽  
Plasma Reactors

Abstract The use of silicon nanoparticles for lithium-ion batteries requires a precise control over both their average size and their size distribution. Particles larger than the generally accepted critical size of 150 nm fail during lithiation because of excessive swelling, while very small particles (<10 nm) inevitably lead to a poor first cycle coulombic efficiency because of their excessive specific surface area. Both mechanisms induce irreversible capacity losses and are detrimental to the anode functionality. In this manuscript we describe a novel approach for enhanced growth of nanoparticles to ~20 nm using low-temperature flow-through plasma reactors via pulsing. Pulsing of the RF power leads to a significant increase in the average particle size, all while maintaining the particles well below the critical size for stable operation in a lithium-ion battery anode. A zero-dimensional aerosol plasma model is used to investigate the dynamics of particle agglomeration and growth in the pulsed plasma reactor. The accelerated growth correlates with the shape of the particle size distribution in the afterglow, which is in turn controlled by parameters such as metastable density, gas and electron temperature. The accelerated agglomeration in each afterglow phase is followed by rapid sintering of the agglomerates into single-crystal particles in the following plasma-on phase. This study highlights the potential of non-thermal plasma reactors for the synthesis of functional nanomaterials, while also underscoring the need for better characterization of their fundamental parameters in transient regimes.

Effect of Poly(Vinyl Pyrrolidone) on Dispersing Carbon Black Particles

2013 ◽  
Vol 796 ◽  
pp. 432-436
Author(s):  
Xia Yuan
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Carbon Black ◽  
Ultrasonic Method ◽  
Aqueous Media ◽  
Average Particle Size ◽  
Sodium Dodecyl ◽  
Vinyl Pyrrolidone ◽  
Average Particle ◽  
Poly Vinyl Pyrrolidone

The effects of poly (vinyl pyrrolidone)(PVP) on dispersing carbon black (CB) particles were investigated by measuring Z-average particle size, Zeta potential and centrifugal stability of CB dispersions. Addition of PVP in a dispersing medium significantly reduces the size of suspended CB particles, especially in water. The dispersing efficiency of PVP was found to have been enhanced by adding an anionic surfactant, sodium methylenedinaphthalene disulphonate (NNO) in the aqueous media. The particle size of CB dispersed with PVP and NNO was 175.7 nm, significantly smaller than that dispersed with PVP and sodium dodecyl sulfate (SDS). The performance of PVP-encapsulated CB particles and that of PVP-adsorbed CB particles were also compared. The particle size and Zeta potential of PVP-encapsulated CB particles were similar to those of PVP-adsorbed CB particles using ultrasonic method, but the centrifugal stability of PVP-encapsulated CB dispersions was significantly improved. The relative absorbency of PVP/CB dispersions was increased from 42.0% to 63.7%. However, the PVP-encapsulated layer can be destroyed by prolonged ultrasonic treatment because the ultrasound over a long period of time can not only break up the flocculation bridge in the crosslinking matrix of PVP, but also flake off the PVP shells on the surface of CB particles.

Carbon Black in Rubber Compounding

1941 ◽  
Vol 14 (1) ◽  
pp. 98-112 ◽  
Author(s):  
D. Parkinson
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Fine Particle ◽  
Average Particle Size ◽  
Average Particle ◽  
Small Particles ◽  
Surface Development ◽  
Fine Particle Size ◽  
Filler Reinforcement ◽  
Methods Of Measurement

Abstract The mechanism of filler reinforcement has not yet been fully explained, but there is general agreement that an important, probably the most important, factor is the enormous surface development between the rubber and filler due to the fine particle size of the filler. Explanations have been attempted to show how small particles can cause reinforcement, but a complete theory of the phenomenon which accounts for all the facts is still awaited. Particle size oj carbon blacks.—A knowledge of this property is important in an understanding of the mechanism of reinforcement by carbon black. Because of the difficulty of distinguishing between ultimate particles and compact aggregates, and because the particles themselves are too small to be resolved in an ordinary microscope, the usual microscopical methods of measurement are inapplicable. Ultramicroscopical methods have been used with some success, the results obtained by the method of Gehman and Morris being probably the most reliable. These authors quote an average particle size of 61µµ for a sample of a standard rubber gas black (Micronex). The figures given for P-33 black, Shawinigan acetylene black and Thermatomic black are 159µµ, 130µµ and 1120µµ, respectively.

scholarly journals Effective Removal of Amido Black and Eosin B Dyes in Aqueous Solution by MWCNT/ZrO2/Pb Nanocomposites: Isotherm, Reusability and Kinetic Studies

2021 ◽  
Author(s):  
Marjan Sheibani ◽  
Mehrorang Ghaedi ◽  
Vahid Zare-Shahabadi ◽  
Arash Asfaram
Keyword(s):  
Aqueous Solution ◽  
High Efficiency ◽  
Average Particle Size ◽  
Theoretical Data ◽  
Kinetic Studies ◽  
Average Particle ◽  
Operational Conditions ◽  
Eosin B ◽  
Amido Black ◽  
Multi Walled Carbon Nanotubes

This research illustrates modification of multi-walled carbon nanotubes (MWCNT) by ZrO2/Pb to construct nanocomposites (MWCNT/ZrO2/Pb-NCs) by simple precipitation technique and subsequently examine its ability for adsorption of Amido black (AB) and Eosin B (EB) dyes in binary system. The present nanocomposites investigation by FESEM, XRD, FTIR, and EDX analysis, reveal its as-synthesized crystalline nature with cubic morphology and average particle size 30&ndash;50 nm. The present nano-adsorbent represent high efficiency for AB and EB adsorption from aqueous solution, while dependency of variables including pH, initial concentration of dyes, contact time and MWCNT/ZrO2/Pb-NCs mass were analyzed by central composite design (CCD). The predicted maximum removal percentage was 95% removal for both dyes is consequence of adjustment of operational conditions at pH of 6.0; 0.05 g MWCNT/ZrO2/Pb-NCs; 15&thinsp;min stirring at 15 mg L-1 for both dyes. The Langmuir as applicable for representation and description of reveal data of adsorption with adsorption capacity of 15.46 and 16.92 mg g-1 for AB and EB, respectively. Pseudo-first order model owing to its high correlation coefficient and closeness of experimental and theoretical data well represented behavior of corresponding adsorption system. Mechanism examination strongly proof high contribution of external mass transference as the main rate-controlling step. The successful regeneration of MWCNT/ZrO2/Pb-NCs suggested their usefulness in wastewater treatment and its ability of environmental management.

scholarly journals Effect of the stirring speed on the struvite formation using the centrate from a WWTP

2019 ◽  
pp. 42-50 ◽  
Author(s):  
Carolina Gonzalez Morales ◽  
Miller Alonso Camargo-Valero ◽  
Francisco José Molina Pérez ◽  
Belén Fernández
Keyword(s):  
Particle Size ◽  
Wastewater Treatment Plants ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Mean Values ◽  
X Ray ◽  
Operational Conditions ◽  
Significant Difference ◽  
Speed Range

The formation of struvite (MgNH4PO4·6H2O) for nutrient recovery in wastewater treatment plants has been widely investigated; however, little attention has been paid to the effect of stirring speeds on the resulting particle size, which could affect its agronomic value as a slow-release fertilizer. In this study, struvite formation from the centrate of sewage digestate was performed under six stirring speeds (0, 100, 200, 300, 400, 500 rpm). The resulting struvite crystals were characterised using X-ray diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy. The average particle size of struvite crystals increased from 55 µm at 0 rpm to 127 µm at 100 rpm and 128 μm at 200 rpm.  Further increments in stirring speeds resulted in smaller crystal sizes. These results indicated that the largest particle size can be obtained at stirring speeds ranging from 100 to 200 rpm, equivalent to a velocity gradient between 79 and 188 s-1, as there was no statistically significant difference between mean values (t-test, p<0.05). The optimum stirring speed range reported herein can be used to set operational conditions for struvite crystallisation with the benefit of producing large crystals and reducing energy consumption in stirring tanks.

Microwave Synthesis of Nano-Titanium Carbide

2011 ◽  
Vol 399-401 ◽  
pp. 561-564 ◽  
Author(s):  
Ping An Liu ◽  
Qing Song Yang ◽  
An Ze Shui ◽  
Hui Wang ◽  
Xiao Su Cheng ◽  
...  
Keyword(s):  
Particle Size ◽  
Low Temperature ◽  
Carbon Black ◽  
Titanium Carbide ◽  
Microwave Synthesis ◽  
Average Particle Size ◽  
Synthesis Method ◽  
Synthesis Temperature ◽  
Synthesis Rate ◽  
Average Particle

A new synthesis technology of titanium carbide with microwave is introduced in this article. Microwave synthesis technology is a fast and relatively low temperature of synthesis method. Nano-titanium carbide powders were synthesized by carbothermal reduction of titanium dioxide and carbon black with the microwave synthesis method at 1100°C-1400°C in argon gas atmosphere. Nano-TiO2powder and carbon black were used as raw materials. The TiC powders were characterized with the XRD and TEM. The experimental results show that the synthesis rate is quick, even at relatively low synthesis temperature. The average particle size of the TiC powders synthesized by the microwave synthesis technology under low temperature (<1300°C) is less than 50nm, and the average particle size augments with increasing the microwave synthesis temperature and time.

Measurement of Average Particle Size of Fine Pigments

1932 ◽  
Vol 5 (2) ◽  
pp. 202-215 ◽  
Author(s):  
S. D. Gehman ◽  
T. C. Morris
Keyword(s):  
Particle Size ◽  
Zinc Oxide ◽  
Carbon Black ◽  
Wave Length ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Carbon Blacks ◽  
Count Method

Abstract A method of obtaining excellently dispersed suspensions of rubber pigments of accurate concentration is described in which the pigment is milled into rubber and the stock then dissolved in a solvent. The average particle sizes of carbon blacks measured by the Zsigmondy count method were found to range from 0.061μ for rubber gas black to 2.22μ for the coarsest one measured. The zinc oxide pigments had average particle sizes from 0.076μ to 0.57μ.. Measurements on several other pigments of interest are included. Because of the high visibility in the ultra-microscope, this method gives smaller values for average particle size than the photomicrographic methods. The results have been used to calibrate a microturbidimeter of the extinction type for use in measuring average particle size. Curves are included showing how the turbidities of suspensions of zinc oxide and carbon black vary with the average particle size, concentration, and wave length of light used.

Amorphous calcium phosphate nano-powders made from radio frequency (RF) plasma spraying

2003 ◽  
Vol 777 ◽  
Author(s):  
Xu Jinling ◽  
Rajendra Kumar ◽  
K.A. Khor ◽  
P. Cheang
Keyword(s):  
Calcium Phosphate ◽  
Radio Frequency ◽  
Amorphous Calcium Phosphate ◽  
Rietveld Method ◽  
Average Particle Size ◽  
Rf Plasma ◽  
Quantitative Phase Analysis ◽  
Average Particle ◽  
Rf Plasma Spraying ◽  
Spray Dried

AbstractPredominantly amorphous nano powders of calcium phosphate were produced by radio frequency (RF) plasma and subsequently characterised by SEM, TEM and XRD. Quantitative phase analysis was carried out by the Rietveld method. The starting feedstock was comprised of hydroxyapatite (HA) powders spray dried from a suspension. The input parameters were varied to produce predominantly amorphous calcium phosphate powders. Results showed that as the plate power was increased and the flow rate of feedstock was decreased the as-sprayed powders produced were predominantly amorphous. The average particle size of the powders was about 20-40 nm, depending on process parameters, as confirmed by TEM observation. These powders are thought to have excellent bio-resorbability and are targetted for use in gene and drug delivery technologies. These nano-sized powders are also envisioned to enhance the mechanical properties of bulk products sintered by appropriate techniques.

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