Tantalum and niobium powder preparation from their oxides by calciothermic reduction in the molten CaCl2

被引:67
作者
Baba, M [1 ]
Ono, Y [1 ]
Suzuki, RO [1 ]
机构
[1] Kyoto Univ, Dept Energy Sci & Technol, Sakyo Ku, Kyoto 6068501, Japan
关键词
electronic materials; chemical synthesis; crystal growth;
D O I
10.1016/j.jpcs.2004.06.042
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Calciothermic reductions of Ta2O5 and Nb2O5 are proposed aiming at the fine powder preparation for the larger capacitance of condensers. Because the molten CaCl2 can coexist stably with metallic Ca, and because it can dissolve a few mol%Ca and about 20 mol%CaO, the reductant Ca can be supplied to the oxide via molten CaCl2, and the reaction by-product CaO can be in situ eliminated from the reaction interface. The metallic powder was obtained after an hour at 1173 K. In the prolonged time the particles sintered together, but oxygen was gradually removed to the level of a few thousands ppm. (c) 2004 Elsevier Ltd. All rights reserved.
引用
收藏
页码:466 / 470
页数:5
相关论文
共 21 条
[1]   THERMODYNAMIC PROPERTIES OF CALCIUM + CALCIUM-CHLORIDE SYSTEM MEASURED BY AN ELECTROCHEMICAL TECHNIQUE [J].
DOSAJ, V ;
AKSARANAN, C ;
MORRIS, DR .
JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS I, 1975, 71 (05) :1083-1098
[2]   THERMODYNAMIC DATA FOR LIQUID CA-CAF2 AND CA-CACL2 SLAGS [J].
FISCHBACH, H .
STEEL RESEARCH, 1985, 56 (07) :365-368
[3]  
HORZ G, 1981, PHYSIK DATEN GASES 8, P24
[4]   Solid state deoxidation of niobium by calcium and magnesium [J].
Liu, S ;
Suzuki, RO ;
Ono, K .
JOURNAL OF ALLOYS AND COMPOUNDS, 1998, 266 (1-2) :247-254
[5]   DETERMINATION OF THE GIBBS ENERGY OF SOLUTION OF OXYGEN IN NIOBIUM [J].
NIIYAMA, H ;
TSUKIHASHI, F ;
SANO, N .
JOURNAL OF ALLOYS AND COMPOUNDS, 1992, 179 :L1-L5
[6]   DEOXIDATION EQUILIBRIUM OF SOLID TITANIUM, ZIRCONIUM AND NIOBIUM WITH CALCIUM [J].
NIIYAMA, H ;
TAJIMA, Y ;
TSUKIHASHI, F ;
SANO, N .
JOURNAL OF THE LESS-COMMON METALS, 1991, 169 (02) :209-216
[7]  
Okabe T.H., 1992, B JAPAN I METALS, V31, P315
[8]   PRODUCTION OF EXTRA LOW OXYGEN TITANIUM BY CALCIUM HALIDE FLUX DEOXIDATION [J].
OKABE, TH ;
SUZUKI, RO ;
OISHI, T ;
ONO, K .
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN, 1991, 77 (01) :93-99
[9]   Production of niobium powder by electronically mediated reaction (EMR) using calcium as a reductant [J].
Okabe, TH ;
Park, I ;
Jacob, KT ;
Waseda, Y .
JOURNAL OF ALLOYS AND COMPOUNDS, 1999, 288 (1-2) :200-210
[10]   THERMODYNAMIC PROPERTIES OF DILUTE TITANIUM-OXYGEN SOLID-SOLUTION IN BETA PHASE [J].
OKABE, TH ;
SUZUKI, RO ;
OISHI, T ;
ONO, K .
MATERIALS TRANSACTIONS JIM, 1991, 32 (05) :485-488