Direct Electrolytic Reduction of Solid Cr2O3 to Cr Using SOM Process

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Cr metal directly from Cr2O3 in molten CaCl2. The sintered porous Cr2O3 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. The particle sizes and porosity of the cathode pellets are important factors that have significant impact on the electrolysis process. The optimal experimental condition is pellet forming pressure 4MPa, sintering and electrolytic temperature 1150°C, cell voltage 3.5V, electrolysis time 2h.

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Extraction of Tantalum from Ta2O5 Using SOM Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.25 ◽

2013 ◽

Vol 690-693 ◽

pp. 25-29 ◽

Cited By ~ 1

Author(s):

Chao Yi Chen ◽

Ying Lu Lv ◽

Jun Qi Li

Keyword(s):

Liquid Copper ◽

Cell Voltage ◽

Graphite Powder ◽

Yttria Stabilized Zirconia ◽

Particle Sizes ◽

Electrolysis Time ◽

Stabilized Zirconia ◽

Experimental Conditions ◽

Oxygen Ion ◽

Ion Conducting

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Ta metal directly from Ta2O5 in molten CaCl2. The sintered porous Ta2O5 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. The particle sizes and porosity of the cathode pellets are important factors that have significant impact on the electrolysis process. The optimal experimental conditions is pellet sintering and electrolytic temperature 1100°C, cell voltage 3.5V, electrolysis time 2h.

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Direct Preparation of Tantalum Metal from Ta2O5

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.2312 ◽

2013 ◽

Vol 275-277 ◽

pp. 2312-2316

Author(s):

Chao Yi Chen ◽

Jun Qi Li ◽

Xiong Gang Lu

Keyword(s):

Liquid Copper ◽

Graphite Powder ◽

Electrochemical Process ◽

Solid Oxide ◽

Yttria Stabilized Zirconia ◽

Stabilized Zirconia ◽

Oxygen Ion ◽

Direct Preparation ◽

Ion Conducting ◽

Electrolysis Potential

A novel process of solid-oxide-oxygen-ion conducting membrane (SOM) technique has been investigated to produce Ta metal directly from solid Ta2O5 in mixture molten of 55.5MgF2-44.5CaF2 (in wt%). The sintered porous Ta2O5 pellet was employed as the cathode while liquid copper, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. An electrolysis potential higher than that in Fray–Farthing–Chen (FFC) Cambridge process could be applied to this process because YSZ membrane blocked the electrolysis of the melts and there was no need for flux to dissolve Ta2O5. The results demonstrated that the electrolytic temperature have played important roles in this electrochemical process. Furthermore, this process can be used to efficiently produce Ta metal without the expensive pre-electrolysis and generation of harmful byproducts.

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Direct Extraction of Ti and Ti Alloy from Ti-Bearing Dust Slag in Molten CaCl2

High Temperature Materials and Processes ◽

10.1515/htmp-2014-0235 ◽

2016 ◽

Vol 35 (6) ◽

pp. 591-597

Author(s):

Chaoyi Chen ◽

Chong Zhao ◽

Junqi Li ◽

Shufeng Yang

Keyword(s):

Liquid Copper ◽

Pure Titanium ◽

Graphite Powder ◽

Yttria Stabilized Zirconia ◽

Stabilized Zirconia ◽

Direct Extraction ◽

Oxygen Ion ◽

Porous Cathode ◽

Ion Conducting ◽

Impurity Elements

AbstractUsing process of solid oxygen-ion conducting membrane (SOM), titanium metal and its alloy can be prepared directly from Ti-bearing dust slag by immersing it in the molten CaCl2 at 1,100℃, which has been proposed by constant voltage of 3.5 V for 2–6 h. The dust slag was ball-milled and pressed into pellets, then employed as the cathode, while the liquid copper, which was saturated with graphite powder and encased in yttria-stabilized zirconia (YSZ) tube, acted as the anode. The effect of forming pressure and electrolytic time on products was analyzed. The results show that the content of titanium increased with electrolytic time and the characteristic morphology presents as granule. Ti–Fe alloy can be obtained from Ti–Fe residue by 6 h electrolysis. For titanium-rich residue, when the forming pressure of pellets decreased from 6 to 3 MPa, only electrolysis for more than 4 h can completely remove the oxygen, and pure titanium is obtained by 6 h electrolysis. Besides, there is an unprecedented finding that the porous cathode is conducive to the removal of impurity elements.

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Electro-Reduction of Ilmenite to FexTi Alloys in Molten CaCl2

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.548-549.172 ◽

2014 ◽

Vol 548-549 ◽

pp. 172-176

Author(s):

Xing Li Zou ◽

Xiong Gang Lu ◽

Wei Xiao ◽

Shan Lin Gu ◽

Bin Shen

Keyword(s):

Phase Composition ◽

Reaction Mechanism ◽

Reduction Process ◽

Solid Oxide ◽

Particle Sizes ◽

Green Method ◽

Oxygen Ion ◽

Ti Alloys ◽

Reduction Experiment ◽

Ion Conducting

This paper reports the preparation of FexTi alloys from natural ilmenite by electro-reduction in molten CaCl2. The electro-reduction experiment was carried out at 1000 °C and potential of 3.8 V, and an inert solid oxide oxygen-ion-conducting membrane (SOM) anode system was used to control the electrochemical experiment. The phase composition and morphology of the final product were investigated. The reaction mechanism involved in the electro-reduction process is discussed based on our experimental results and thermodynamic analysis. It is suggested that FexTi alloys powder with different Fe contents (FexTi, 0 ≤ x ≤ 2) and particle sizes can be obtained by controlling electrolysis conditions strictly. The result implies that the SOM process is a promising green method for the preparation of ferrotitanium alloys direct from natural ilmenite.

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Extraction of Ti and Ti Alloy from Titaniferous Residue Using SOM Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.550-553.1811 ◽

2012 ◽

Vol 550-553 ◽

pp. 1811-1816 ◽

Cited By ~ 1

Author(s):

Chao Yi Chen ◽

Jun Qi Li ◽

Xiong Gang Lu

Keyword(s):

Liquid Copper ◽

Graphite Powder ◽

Ti Alloy ◽

Constant Voltage ◽

Characteristic Morphology ◽

Oxygen Ion ◽

Solid Oxygen ◽

Ion Conducting

Using process of Solid Oxygen-ion conducting Membrane (SOM), to produce Ti and Ti alloy directly from Titaniferous residue in molten CaCl2 were proposed by constant voltage (3.0～3.5V) for electrolysis 2~6h at 1100°C. The residues were ball-milled and pressed into pellets as the cathode, and the liquid copper was saturated with graphite powder and encased in YSZ tube as the anode. The results show that the content of Ti increase with electrolytic time, the characteristic morphology present as granule. Ti-Fe alloy is obtained from Ti-Fe residue during electrolysis 6h. For Ti -rich residue, when the forming pressure of pellets from 6MPa decrease to 3MPa, only electrolysis for 4h can completely remove the oxygen, and pure Ti is obtained for electrolysis 6h, this is an unprecedented finding.

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