Research on Effect Factors of Current Efficiency in the Process of Sponge Titanium Production by Electrolytic Method

This paper systematically analyzes the various factors that affect the current efficiency in the process of sponge titanium production by vacuum molten salt electrolysis method. The research result shows that firstly, when electrolysis is undertaken in CaCl2 molten salt system under the condition that the pressure is under 101Pa, temperature is at 850°C, space between electrodes is 5 cm, cathodic current density is 1.05 A.cm-2 and anodic current density is 0.8A.cm-2 , the reoxidation of sponge titanium can be effectively avoided, the loss of electric current can be reduced and current efficiency can be greatly improved. Secondly, current efficiency can be greatly improved when mix molten salt system CaCl2+A is adopted, which can greatly reduce the electrolysis temperature and the resistance of molten salt. Thirdly, current efficiency can be greatly improved through selecting appropriate vacuum degree, appropriate molten salt system, appropriate space between electrodes, appropriate current density; in addition, keeping tidy reduction cell inside and adopting high-purity molten salt and raw material TiO2 are another ways for current efficiency improvement.

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Electrolytic Preparation of Al-Sm Alloy in SmF3-LiF-Sm2O3 Molten Salt System

Materials Science ◽

10.5755/j01.ms.25.4.20437 ◽

2019 ◽

Vol 25 (4) ◽

pp. 466-470

Author(s):

Xiaolian ZHANG ◽

Chubin YANG ◽

Hongxia LIU ◽

Guanghuai PENG

Keyword(s):

Current Efficiency ◽

Molten Salt ◽

Current Density ◽

Cathode Current Density ◽

Electrolyte Composition ◽

Salt System ◽

Liquid Cathode ◽

Cathode Current ◽

Electrolytic Preparation ◽

Molten Salt System

In the present paper, an Al rod as liquid cathode was added into the SmF3-LiF-Sm2O3 molten salt system and subsequently the Al-Sm alloy was prepared by the liquid cathode electrolysis method. The effects of electrolysis temperature, cathode current density and electrolyte composition on the current efficiency were studied. The results demonstrated that the maximum content of Sm in the Al-Sm interalloy could reach up to 32.8 wt.%, whereas the alloy was mainly composed of the Al substrate, Al4Sm and Al3Sm phases. The current efficiency increased first subsequently decreased as the electrolysis temperature and cathode current density increased. Simultaneously, the electrolyte composition had a high impact on the current efficiency. When the mass ratio of SmF3and LiF was 4, the current efficiency was 62.8 %.

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Thermodynamic Assessment of the NaCl-DyCl3 Molten Salt System

High Temperature Material Processes An International Quarterly of High-Technology Plasma Processes ◽

10.1615/hightempmatproc.v3.i1.70 ◽

1999 ◽

Vol 3 (1) ◽

pp. 77-89

Author(s):

F. Da Silva

Keyword(s):

Molten Salt ◽

Thermodynamic Assessment ◽

Salt System ◽

Molten Salt System

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Molecular Dynamics Simulation Study of the Effect of Ni, Fe, Cu on Cryolite Molten Salt System 78% Na3AlF6-9.5%AlF3-5.0%CaF2-7.5%-Al2O3

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1026.39 ◽

2021 ◽

Vol 1026 ◽

pp. 39-48

Author(s):

Han Bing He ◽

Yu Si Wang ◽

Ze Xiang Luo ◽

Jing Zeng

Keyword(s):

Molecular Dynamics ◽

Diffusion Coefficient ◽

Molten Salt ◽

Diffusion Mechanism ◽

Research Work ◽

Dynamics Simulation ◽

Salt System ◽

Electrolyte System ◽

Aluminum Composite ◽

Molten Salt System

The effect of different additives Ni, Fe, Cu on the structure and properties of electrolyte system 78% Na3AlF6- -9.5%AlF3-5.0%CaF2-7.5%Al2O3 at 1200K and 1.01Mpa was studied by molecular dynamics method. The radial distribution function, coordination number, diffusion coefficient, conductivity, and viscosity of the system were discussed in detail. The results demonstrated that the order of the self-diffusion coefficient of ions in the electrolyte system is: Na+ > F- > O2- > Ca2+ >Al3+. The addition of Ni and Fe connected the free aluminum composite ion groups in the system through fluorine bridges, which enhanced the interaction between Al3+ and Al3+. The addition of Cu weakened the interaction between Al3 + and Al3+ and the F-. The interaction between Al3+ and Na+, [AlF7]4- ionic groups might appeared in the melt system. After adding NiO, Fe2O3, and Cu, the electrical conductivity of the system increased, and the viscosity decreased. The research work revealed the influence of Ni, Fe, Cu on the ion existence form, mobility, inter-ion interaction and diffusion mechanism of cryolite molten salt system, which has important guiding significance for aluminum electrolysis production.

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First-principles molecular dynamics investigation on KF-NaF-AlF3 molten salt system

Chemical Physics Letters ◽

10.1016/j.cplett.2019.06.060 ◽

2019 ◽

Vol 730 ◽

pp. 587-593 ◽

Cited By ~ 1

Author(s):

Hui Guo ◽

Jie Li ◽

Hongliang Zhang ◽

Tianshuang Li ◽

Jiawei Luo ◽

...

Keyword(s):

Molecular Dynamics ◽

Molten Salt ◽

First Principles ◽

Salt System ◽

Molten Salt System ◽

First Principles Molecular Dynamics

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ChemInform Abstract: Experimental Observations of a Thoria Oxide-Ion Sensor in a Molten Salt System.

ChemInform ◽

10.1002/chin.200220015 ◽

2010 ◽

Vol 33 (20) ◽

pp. no-no

Author(s):

S. X. Li ◽

S. D. Herrmann

Keyword(s):

Molten Salt ◽

Salt System ◽

Ion Sensor ◽

Molten Salt System ◽

Oxide Ion

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Effect of Na3WO3F3 Content on the Liquidus Temperature of NaCl-KCl-Na3WO3F3 Molten Salt System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.908.159 ◽

2014 ◽

Vol 908 ◽

pp. 159-162

Author(s):

Jie Li ◽

Yang Pei ◽

Ya Bin Liu ◽

Yun Gang Li

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

Molten Salt ◽

Liquidus Temperature ◽

Eutectic Composition ◽

Eutectic Temperature ◽

Salt System ◽

Molten Salt System

The liquidus temperature of molten salt NaCl-KCl-Na3WO3F3 system was measured by differential thermal analysis. The results show that in the molten salt system when XNaCl:XKCl=1:1, XNa3WO3F3<0.6 the liquidus temperature decreased with increase of Na3WO3F3 content; when XNaCl:XKCl=1:1, XNa3WO3F3> 0.6 the liquidus temperature increased with the increase of Na3WO3F3 content; the eutectic temperature is 612.9 °C, the eutectic composition is XNaCl=0.2, XKCl=0.2, XNa3WO3F3=0.6.

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Preparation of Al-Sc Alloy by LiF-ScF3-ScCl3 Molten Salt Electrolysis

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.1125 ◽

2011 ◽

Vol 675-677 ◽

pp. 1125-1128 ◽

Cited By ~ 1

Author(s):

Rui Guo ◽

Xiu Jing Zhai ◽

Ting An Zhang

Keyword(s):

Molten Salt ◽

Base Alloy ◽

Process Condition ◽

Cell Voltage ◽

Scandium Oxide ◽

Raw Material ◽

Electrolysis Time ◽

Molten Salt Electrolysis ◽

Aluminum Base Alloy ◽

Aluminum Base

The paper studied the preparation of Al-Sc alloy by molten salt electrolysis. LiF-ScF3-ScCl3 as the electrolyte, Sc2O3 as raw material, liquid Al as cathode and graphite as anode. The process condition of preparating Al-Sc alloy includes the influence of current density, electrolysis time, temperature of electrolysis, Back EMF, content of Sc in alloy and current efficiency.The content of Sc in alloy prepared by this method has reached to the maximum of 3.437%. The components of alloys showed by SEM were uniform, it is applicable for commercial purposes. Preparation of Al-Sc alloys with scandium oxide as raw materials, it not only reduce environment pollution, but also decease the cost of production. It is reported in many documents, preparing aluminum base alloy by the method of molten salt electrolysis[1-3], people could make many alloys such as Al-Ce、Al-La、Al-RE、Al-Ti、Al-Si-Ti in the aluminum cell, also the method to prepare some rare earth alloys such as Al-Sr、Nd-Fe、La-Ni was reported[4,5]. Use the method of electrolysis to produce some aluminum base alloy with high-melting-point , difficult to restore , high-priced element is a good method because it is technological process is brief, economy is rational, the technology is feasible, this viewpoint is broadly approved in the world[6]. It isn’t necessary to use high-priced Sc as raw material in preparing Al-Sc alloy with molten salt electrolysis, it could control the Sc amounts in the alloy through the different current efficiency and electrolysis time, production in this method could be continuous or semi-continuous, so it is easy to be automatic controlled. A new molten salt system is used in this paper, we use molten salt electrolysis to produce Al-Sc alloy, take scandium oxide as raw material, through the study of the effect of the current intensity，electrolysis time and the electrolysis temperature , Back EMF and cell voltage, the final production Al-Sc alloy contains Sc 2~6%.

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