Extraction of titanium from different titania precursors by the FFC Cambridge process
Extraction of titanium from different titania precursors by the FFC Cambridge process
复制标题
通过 FFC 剑桥工艺从不同的二氧化钛前体中提取钛
DOI：
10.1016/j.jallcom.2005.10.048
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发表时间：
2006-08-31
影响因子：
6.2
通讯作者：
Chen, George Z.
中科院分区：
文献类型：
--
作者：
Ma, Meng;Wang, Dihua;Chen, George Z.
以廉价的二氧化钛前驱体，包括二氧化钛粉尘、偏钛酸(固体)和富钛渣为原料，在实验室规模的FFC剑桥工艺中进行了试验。利用恒压电解法(2.9~3.1V)，在氯化钙熔体(900℃)中，成功地将前驱体的多孔球(直径约20 mm，厚度约2.0~3.0 mm)还原为钛金属或钛合金。还原过程与前驱体的初始晶体结构无关。更重要的是，电解后富钛渣中的一些金属杂质，如铝和锰，被部分或全部去除。电流效率随着电解时间的延长而降低，对于2 mm厚的TiO2微球，电流效率一般从前5h的40%下降到12h的20%。当生产的金属含氧量降至3000ppm以下时，电解能耗约为33kWh/kg钛。对部分还原氧化物球团的电解数据和物相组成的分析表明，在球团表面金属化后，电还原强烈依赖于球团的质量(离子)传递。将较早提出的“双熔盐电解法”与电解数据进行了比较，重点讨论了背景电流的来源和影响。(C)2005 Elsevier B.V.保留所有权利。
Cheap titania precursors including titania dust, metatitanic acid (solid) and titanium-rich slag were tested as the feeding materials in the FFC Cambridge process (laboratory scale). Porous pellets (similar to 20 mm in diameter, 2.0-3.0 mm in thickness) of the precursor were successfully reduced to titanium metal or alloy by constant voltage electrolysis (2.9-3.1 V) in molten calcium chloride (similar to 900 degrees C). The reduction was independent of the initial crystal structure of the precursor. More importantly, some metallic impurities in the titanium-rich slag, such as aluminium and manganese, were found to be partly or completely removed after electrolysis. The current efficiency decreased with electrolysis time, typically from 40% in the first 5 It to 20% in 12 h for the 2 mm thick TiO2 pellets. The energy consumption of electrolysis was about 33 kWh/kg Ti when the oxygen level in the produced metal was reduced to below 3000 ppm. Analyses of the electrolysis data and of the phases and compositions in partially reduced oxide pellets suggested strong dependence of the electro-reduction on mass (ion) transfer in the pellet after metallisation of the pellet's surface. An earlier proposed "double-melt electrolysis" was compared with the electrolysis data, focusing on the origin and influence of background current. (c) 2005 Elsevier B.V. All rights reserved.