Thermodynamic analysis and the mechanism of the solid-phase reduction of Cr2O3 with carbon: Part 1

L10 ordered FePt and FePtCu nanoparticles (NPs) with a good dispersion were successfully fabricated by a simple, green, one-step solid-phase reduction method. Fe (acac)3, Pt (acac)2, and CuO as the precursors were dispersed in NaCl and annealed at different temperatures with an H2-containing atmosphere. As the annealing temperature increased, the chemical order parameter (S), average particle size (D), coercivity (Hc), and saturation magnetization (Ms) of FePt and FePtCu NPs increased and the size distribution range of the particles became wider. The ordered degree, D, Hc, and Ms of FePt NPs were greatly improved by adding 5% Cu. The highest S, D, Hc, and Ms were obtained when FePtCu NPs annealed at 750 °C, which were 0.91, 4.87 nm, 12,200 Oe, and 23.38 emu/g, respectively. The structure and magnetic properties of FePt and FePtCu NPs at different annealing temperatures were investigated and the formation mechanism of FePt and FePtCu NPs were discussed in detail.

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Study of the Conversion of Carbon-containing and Organochlorine Impurities in the Process of Hydrogen Reduction of Silicon Tetrachloride by RF (40.68 MHz) Arc Discharge.

Plasma Physics and Technology Journal ◽

10.14311/ppt.2019.2.111 ◽

2019 ◽

Vol 6 (2) ◽

pp. 111-114

Author(s):

R. Kornev ◽

P. Sennikov ◽

V. Nazarov ◽

A. Kut'in ◽

A. Plekhovich

Keyword(s):

Field Strength ◽

Electric Field ◽

Electric Field Strength ◽

Thermodynamic Analysis ◽

Atmospheric Pressure ◽

Hydrogen Reduction ◽

Solid Phase ◽

Arc Discharge ◽

Silicon Tetrachloride ◽

High Electric Field Strength

A contracted RF (40.68 MHz) arc discharge of atmospheric pressure, stabilized between two rod electrodes, was used to obtain trichlorosilane by the reaction of hydrogen reduction of silicon tetrachloride (SiCl4). In model mixtures of macro-composition in the ratio H2/SiCl4/CCl4=10/1/1, it was shown that C and SiC are the main solid-phase product which are deposited on the surface of electrodes in the form of dendrides. The temperature of the ends of the electrodes determined using emission thermometry is 1600 K. The thermodynamic analysis of H2+SiCl4+CCl4 system confirms that the formation of C and SiC occurs in the temperature range of 1600 K. The deposition of solid-phase products occurs on the electrodes in the zone of high electric field strength.

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The Metallurgical Characterization of Iron-Containing Concentrate

Materials Science Forum ◽

10.4028/www.scientific.net/msf.989.428 ◽

2020 ◽

Vol 989 ◽

pp. 428-433

Author(s):

B.M. Myrzaliev ◽

Kulgamal A. Nogaeva ◽

E.B. Kolmachikhina

Keyword(s):

Solid Phase ◽

Metallic Copper ◽

Iron Alloys ◽

Metallic Phase ◽

Phase Reduction ◽

Slag Copper ◽

Metallurgical Characterization ◽

Two Phases ◽

Metallization Process

The expediency of processing iron-containing concentrate with low iron content, increased content of manganese and copper is considered in the article. To process such a concentrate, a metallization process is proposed to produce sponge iron with a reducing agent - carbon. It was found that in solid-phase reduction at 1150 °C iron is reduced to a greater extent, as well as small particles with a copper content of about 95%, manganese is not recovered. The simulation process of metallization with carbon at a temperature of 1250 °C shows that iron is mainly distributed in the metallic phase, to a lesser extent in slag phases, manganese is distributed in two phases - metal and slag, copper is presented as a separate phase of metallic copper in the composition with iron alloys, and also composes a part of iron alloys. The reduction degree from concentrate to the metallic part is 80 - 91% for iron and 95 - 98% for copper. The presence of metallized particles of various sizes, representing phases of iron with manganese and copper was found in the slags.

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