| Titanium is a kind of structural and functional material, which has many desirable properties, such as being light, strong, corrosion-resistant, and widely temperature adaptability. But the extraction of titanium is difficult. Even more, the purity of titanium that industry has required is high, which makes the process of preparation of Ti more complicated. At present, as a traditional process, Kroll method is utilized in industry, but there also exist a lot of problems, such as, complexity of the technology; long production cycle; intermittent operation and so on. From 2000 to now, electrochemical reduction of titanium dioxide has drawn great attention for the metallurgical researchers at home and abroad. It is a kind of new metallurgical process, which is low energy consumption and friendly to the environment. At present, based on this new process, there are many new extraction processes of titanium, such as FFC, EMR, OS and so on, in all of which FFC will be the most promising process.In this article, technical process and experimental apparatus were improved and perfected based on FFC. Finally, titanium was prepared through a series of experiments of molten salt electrolysis. Experiment can be proceeded well through the improvement of experimental apparatus, the pretreatment of molten salt and argon. In the preparation of cathode, it is shown that the porosity of TiO2 was augmented through the agglomeration technology of TiO2 mixed with carbon powder. And through the relevant calculation, the porisuty of TiO2 mixed with carbon powder or not are respectively 36.45% and 34.61%. Oxygen pressure needed in the experiment is very low, through the calculation, it is shown that increasing the current velocity and time of inlet of argon made the oxygen pressure reduce low enough, which ensured the experiment proceeded well.Through thermodynamics calculation,theoretical decomposition voltages about step-by-step reduction of TiO2 have been achieved. It is shown that the theoretical decomposition voltage at which TiO2 is directly electrolyzed is high, but the theoretical decomposition voltages at which TiO2 is electrolyzed step-by-step are relatively low. So the preparation of Ti by direct electrochemical reduction of solid TiO2 is conducted step by step. Loading different voltages in different stages can improve current efficiency. Experimental results have shown that, high purity of titanium have been gotten through preparation of Ti by molten salt electrolysis of TiO2. The electrolysis of TiO2 is... |
