WO_3在NaCl-KCl-NaF-Na_2WO_4熔盐体系中的溶解度及溶解机理

利用等温饱和法研究温度和熔盐组分对WO_3在KCl-Na Cl-NaF-Na_2WO_4熔盐体系中溶解度的影响。利用热力学软件Factsage6.4对该熔盐体系各物质之间可能存在的反应进行计算,结合X射线衍射对熔盐急冷试样进行分析,确定WO_3的溶解机理。结果表明,WO_3的溶解机理为52Na_2WO_4(l)+96WO_3(s)=49Na2W_2O_7(l)+2NaO_2(l)+2Na2O2(l)+50WO2.9(l),并且WO_3的溶解度随温度的升高而增大,随Na_2WO_4含量增大而减小,随Na F含量升高而先增大后减小,在xNa F=0.385时达最大值。

Solubility and dissolving mechanism of WO3in KCl-NaCl-NaF-Na2WO4molten salt

The influence of temperature and component to solubility of WO3 in KCl-NaCl-NaF-Na2WO4 molten salt was researched by isothermal saturation method. The possible reactions between the materials in the molten salt system are calculated by using the thermodynamic software Factsage6.4 and the X ray diffraction analysis is carried out for the rapid cooling of molten salt, and finally the dissolution mechanism of WO3 was determined. The results show that dissolving mechanism of 26 Na2WO4 (s) 48WO3 (s)= 24.5 Na2W2O7l) NaO2 (l) Na2O2l) 25WO2.9l), the solubility of WO3increases with the increase of temperature, reduce with the increase of Na2WO4 content, the first increased and then decreased with the increase of NaF content , and reached the maximum at XNaF=0.185.