阴极结构对熔盐电脱氧法制备金属钛影响及杂质研究

辛学松; 张强; 张姗姗; 张敏

doi:10.7513/j.issn.1004-7638.2021.06.007

阴极结构对熔盐电脱氧法制备金属钛影响及杂质研究

doi: 10.7513/j.issn.1004-7638.2021.06.007

辛学松^1,,
张强^{1, 2, 3, ,},
张姗姗¹,
张敏⁴

1.
商丘工学院机械工程学院, 河南商丘 476000
2.
贵州大学材料与冶金学院, 贵州贵阳 550025
3.
贵州省冶金工程与过程节能重点试验室, 贵州贵阳 550025
4.
清华大学天津高端装备研究院洛阳先进制造产业研发基地, 河南洛阳 471000

基金项目: 国家自然科学基金（51764007）资助项目。

详细信息

作者简介:
辛学松（1977—），男，河南商丘人，本科，实验师，主要研究方向为钛资源综合利用，E-mail：1179045396@qq.com

通讯作者:
张强（1994—），男，硕士，助教，主要研究方向为资源综合利用、冶金过程中多相模拟，E-mail：861638378@qq.com

中图分类号: TF823
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出版历程
- 收稿日期: 2021-08-21
- 录用日期: 2021-11-19
- 刊出日期: 2021-12-31

Study on the effect of molten salt electro-deoxidation on the preparation of titanium metal

Xin Xuesong^1
,,
Zhang Qiang^{1, 2, 3
, ,},
Zhang Shanshan¹,
Zhang Min⁴

1.
College of Mechanical Engineering, Shangqiu Institute of Technology, Shangqiu 476000, Henan, China
2.
College of Material and Metallurgy, Guizhou University, Guiyang 550025, Guizhou, China
3.
Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving, Guiyang 550025, Guizhou, China
4.
Tianjin Advanced Equipment Research Institute of Tsinghua University Luoyang Advanced Manufacturing Industry Research and Development Base, Luoyang 471000, Henan, China

摘要

摘要: 在高纯氩气气氛下，在CaCl₂熔盐中电解高钛渣制备金属钛，研究了成型压力与阴极片孔隙率的关系以及对电解过程的影响，并采用 XRD、 SEM等分析手段对阴极片及电解后的物相和微观形貌结构进行表征。结果表明：成型压力对阴极片孔隙率有直接影响，随着成型压力升高，阴极孔隙率下降；阴极片的孔隙率直接影响电脱氧过程，适当的孔隙率有利于形成中间产物CaTiO₃和提高电还原速率。4 MPa压制的阴极1050 ℃烧结2 h，孔隙率为34.79%，电解12 h 产物氧含量降低至1.75%，钛含量为95.72%，此时阴极片的电化学性能较好。
- 金属钛 /
- 高钛渣 /
- 熔盐电脱氧法 /
- 成型压力 /
- 阴极结构 /
- 孔隙率 /
- 电化学性能
Abstract: Titanium metal was prepared by electrolysis of high titanium slag in CaCl₂ molten salt under a high-purity argon atmosphere. The relationship between forming pressure and porosity of cathode sheet as well as the influence on the electrolysis process were studied. The phases and microstructures of the cathode sheet and that after electrolysis were characterized by XRD and SEM. The results showed that the forming pressure had a direct influence on the porosity of the cathode sheet, which decreased with the increase of the forming pressure. The porosity of the cathode sheet directly affected the electrode deoxidation process, and an appropriate porosity was beneficial to the formation of intermediate product CaTiO₃ and the increase of the electroreduction rate. The porosity of the cathode pressed by 4 MPa is 34.79% when sintered at 1 050 ℃ for 2 h, and the oxygen content of the product is reduced to 1.75% and titanium content is 95.72% when electrolyzed for 12 h, which shows a better electrochemical performance of the cathode sheet.
- titanium metal /
- high titanium slag /
- molten salt electro-deoxidation method /
- forming pressure /
- cathode structure /
- porosity /
- electrochemical performance

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图 1 电解装置示意

Figure 1. Schematic diagram of the electrolysis cell

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图 2 不同成型压力下阴极的SEM形貌

(a) 2 MPa；(b) 4 MPa；(c) 6 MPa；(d) 8 MPa

Figure 2. SEM images of the cathodes under different molding pressure

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图 3 阴极孔隙率和密度随成型压力变化关系

Figure 3. Plot of the cathode porosity and density as a function of the forming pressure

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图 4 不同压力制备阴极1050 ℃烧结后的SEM形貌

(a) 2 MPa；(b) 4 MPa；(c) 6 MPa；(d) 8 MPa

Figure 4. SEM images of the cathodes sintered at 1 050 ℃ at different pressures

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图 5 不同成型压力阴极产物的XRD物相

Figure 5. XRD spectra of the cathode products under different pressures

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图 6 不同压力下阴极电解产物的SEM形貌

Figure 6. SEM images of the cathode products at different pressure

(a) 2 MPa；(b) 4 MPa；(c) 6 MPa；(d) 8 MPa

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图 7 不同成型压力阴极电流—时间曲线

Figure 7. The current-time curve under different molding pressures

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图 8 吉布斯自由能和标准电解电压随温度变化曲线

Figure 8. Plot of the change of Gibbs free energy and standard electrolytic voltage with temperature

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表 1 高钛渣化学成分

Table 1. Chemical compositions of the high titanium slag %

O	Al	Si	Ti	Fe	Ca
47.45	2.26	1.94	38.53	8.61	1.21

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表 2 不同压力电解后的阴极化学成分

Table 2. Chemical composition of the cathodes after electrolysis under different pressure

成型压力/MPa	w/%
成型压力/MPa	O	Al	Si	Ti	Fe	Ca
2	5.43	0.71	1.09	90.56	1.71	0.50
4	1.75	0.49	0.76	95.72	0.80	0.48
6	3.96	0.45	1.03	93.14	0.92	0.54
8	4.29	0.57	1.05	93.06	0.47	0.56

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表 3 各处理过程的杂质元素含量

Table 3. Impurity element content of various treatment processes mg

	Fe	Al	Si
杂质总量	172.2	45.2	38.8
CaCl₂熔盐	110.41	36.21	26.54
HCl洗涤液	35.12	5.32	6.24
尾气吸收液	1.2	0.62	0.53

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