氟化物体系中熔盐电解制备金属钛的研究  

Study on preparation of titanium metal by molten salt electrolysis in fluoride system

作　　者：杨永辉 颜恒维 杨光 Yang Yonghui;Yan Hengwei;Yang Guang(School of Metallurgy and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China)

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093

出　　处：《轻金属》2023年第2期40-45,共6页Light Metals

基　　金：云南省重大科技项目(No.202202AG050007);国家自然基金项目(NSFC 52064030)。

摘　　要：本方法确定了用NaF-K_(2)TiF_(6)熔体中的TiO_(2)通过熔盐电解法探究直接电解TiO_(2)制备金属钛的可行性。首先通过比较不同摩尔比NaF-K_(2)TiF_(6)体系中的初晶温度,并采用Leco氧分析法测定了TiO_(2)在NaF-K_(2)TiF_(6)体系中的溶解度(饱和浓度),选择较为合适的熔盐体系,并通过恒流电解法研究了四价钛的电还原行为。结果表明在830℃时摩尔比为1.5∶1时TiO_(2)在熔盐体系中的饱和浓度为10.2%,并对该熔盐体系进行热力学计算,发现当以活性炭作为阳极时钛的氧化物相较于氟化物的理论分解电压低,即氧化物会优先反应,通过恒流电解实验发现在电解温度为830℃,阴极电流密度为1 A/cm^(2)时可以得到金属钛,其中TiO_(2)的还原机理可能是通过TiO_(2)→TiO→Ti_(2)O→Ti三步还原反应还原为金属钛。This method determines the feasibility of using TiO_(2)in NaF-K_(2)TiF_(6)melt to explore the direct electrolysis of TiO_(2)to prepare metal titanium by molten salt electrolysis,which is a new attempt to prepare metal titanium by the direct electrolysis of TiO_(2)in fluoride system.First,by comparing the initial crystal temperature of NaF-K_(2)TiF_(6)system with different molar ratios,the solubility(saturation concentration)of TiO_(2)in NaF-K_(2)TiF_(6)system was determined by using the Leco oxygen analysis method,a more appropriate molten salt system was selected,and the electroreduction behavior of tetravalent titanium was studied by constant current electrolysis.The results show that the saturation concentration of TiO_(2)in the molten salt system is 10.2%when the mole ratio is 1.5∶1 at 830℃.The thermodynamic calculation of the molten salt system shows that when the active carbon is used as the anode,the theoretical decomposition voltage of titanium oxide is lower than that of fluoride,that is,the oxide will react preferentially.The constant current electrolysis experiment shows that metal titanium can be obtained when the electrolysis temperature is 830℃and the cathode current density is 1 A/cm^(2),The reduction mechanism of TiO_(2)may be that TiO_(2)→TiO→Ti_(2)O→Ti is reduced to metallic titanium through a three-step reduction reaction.

关 键 词：熔盐电解 NaF-K_(2)TiF_(6) 钛电解 钨棒电极 

分 类 号：TF823[冶金工程—有色金属冶金] TG146.2[一般工业技术—材料科学与工程]