Direct Electrochemical Extraction of Ti5Si3 from Ti/Si-Containing Metal Oxide Compounds in Molten CaCl2

doi:10.1007/s12204-013-1373-6

Abstract

Abstract: Direct electrochemical extraction of Ti5Si3 from pressed cathode pellets comprising of powdered Ti/Sicontaining metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three groups of mixtures including TiO2 mixed with SiO2, Ti-bearing blast furnace slag (TBFS) mixed with TiO2, and TBFS mixed with high-titanium slag (HTS) were prepared at the same stoichiometric ratio (Ti : Si = 5 : 3) corresponding to the target composition of Ti5Si3, and used as the starting materials in this experiment, respectively. The pressed porous cylindrical pellet of the Ti/Si-containing compounds served as a cathode, and two different anode systems, i.e., the inert solid oxide oxygen-ion-conducting membrane (SOM) based anode system and graphite-based anode system were used contrastively. The electrochemical experiment was carried out at 900—1 050℃ and 3.0—4.0 V in molten CaCl2 electrolyte. The results show that the oxide components were electro-deoxidized effectively and Ti5Si3 could be directly extracted from these complex Ti/Si-containing metal oxide compounds.

Key words: electro-deoxidation| oxide compounds| Ti5Si3| molten salts| solid oxide oxygen-ion-conducting membrane(SOM)

摘要： Direct electrochemical extraction of Ti5Si3 from pressed cathode pellets comprising of powdered Ti/Sicontaining metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three groups of mixtures including TiO2 mixed with SiO2, Ti-bearing blast furnace slag (TBFS) mixed with TiO2, and TBFS mixed with high-titanium slag (HTS) were prepared at the same stoichiometric ratio (Ti : Si = 5 : 3) corresponding to the target composition of Ti5Si3, and used as the starting materials in this experiment, respectively. The pressed porous cylindrical pellet of the Ti/Si-containing compounds served as a cathode, and two different anode systems, i.e., the inert solid oxide oxygen-ion-conducting membrane (SOM) based anode system and graphite-based anode system were used contrastively. The electrochemical experiment was carried out at 900—1 050℃ and 3.0—4.0 V in molten CaCl2 electrolyte. The results show that the oxide components were electro-deoxidized effectively and Ti5Si3 could be directly extracted from these complex Ti/Si-containing metal oxide compounds.

关键词: electro-deoxidation| oxide compounds| Ti5Si3| molten salts| solid oxide oxygen-ion-conducting membrane(SOM)

CLC Number:

ZOU Xing-li1 (邹星礼), LU Xiong-gang1* (鲁雄刚), XIAO Wei1 (肖玮), ZHOU Zhong-fu1,2 (周忠福), ZHONG Qing-dong1 (钟庆东), DING Wei-zhong1 (丁伟中). Direct Electrochemical Extraction of Ti5Si3 from Ti/Si-Containing Metal Oxide Compounds in Molten CaCl2[J]. Journal of shanghai Jiaotong University (Science), 2013, 18(1): 111-117.

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