熔盐氯化用熔体组分对体系物性的影响研究

Study on the influences of melt components on the physical properties of molten salt chlorination system

氯化物熔盐物性对于熔盐氯化法制备四氯化钛效率至关重要。为了考察氯化用熔盐组分含量变化对熔盐体系物性的影响规律,以工业生产中的熔盐为对象,对正常原盐、泡沫盐和过滤熔盐的电导率和粘度物性进行了测试以及XRD物相分析、化学成分分析。根据实际生产中的组分配比以及化学分析结果,设置了三因素为FeCl_(2)、FeCl_(3)以及MgCl_(2):NaCl的正交试验,研究不同组分配比下熔盐体系的物性变化。结果表明:FeCl_(2)含量对熔盐体系电导率影响最为显著,每5%的FeCl_(2)增加量会使熔盐整体电导率提高0.33 S/cm;FeCl_(3)含量对熔盐体系粘度影响最大,其组分占比在10%~15%区间内的影响最为明显。最后,利用综合评分法评估出最佳的熔盐氯化组分方案为:CaCl_(2) 4%、FeCl_(2) 20%、FeCl_(3) 5%、MgCl_(2):NaCl=1:1。

The physical properties of chloride molten salt are very important for the preparation efficiency of titanium tetrachloride produced by molten salt chlorination.To investigate the influence of changes in chloride-containing molten salt composition on the physical properties of molten salt systems,this study conducted the physical property tests including conductivity and viscosity on normal raw salt,foam salt and filtered molten salt.Furthermore,XRD analysis and chemical composition analysis were also performed.Based on the component ratios in actual production and chemical analysis results,an orthogonal experiment with three factors including FeCl_(2),FeCl_(3),and MgCl_(2):NaCl was designed to study the changes of physical properties of molten salt systems under different component ratios.The results indicate that the FeCl_(2) content has the most significant effect on the conductivity of the molten salt system,with an increase of 5% FeCl_(2) resulting in a 0.33 S/cm increase in overall molten salt conductivity.The FeCl_(3) content has the greatest impact on the viscosity of the molten salt system,with the effect being most pronounced within the 10% to 15% range of its composition.Finally,utilizing a comprehensive scoring method,the optimal chlorinated component scheme for molten salt was determined to be CaCl_(2) 4%,FeCl_(2) 20%,FeCl_(3) 5% and MgCl_(2):NaCl = 1:1.