摘要
Samarium(Sm) has been widely used in making aluminum(Al)-Sm magnet alloy materials. The research team for this study developed a molten salt electrolyte system which directly produces AI-Sm alloy to replace the energy intensive conventional distillation technology. In this study, molten melt density was measured and operation conditions were optimized to separate AI-Sm alloy product from the fluoride molten melt electrolysis media based on density differences, Archimedes' principle was applied to measure density for the basic molten fluoride system(BMFS: Na_3 AlF_6-AlF_3-LiF-MgF_2)electrolysis media in the temperature range from 905 to 1055 ℃.The impact of temperature(t) and the Al_2O_3 and Sm_2O_3 addition ratio(w_((Al2O3)),w_((Sm2O3)) in the basic fluoride system on molten melt density was examined. The fluoride molten melt density relationship was determined to be:ρ=3.11701-0.00802 w_((Al2O3))+0.027825 w_((Sm2O3))-0.00117 t. The test results showed that molten density decreases with increase in temperature and Al_2O_3 addition ratio, and increases with the addition of Sm_2O_3, and/or Al_2O_3+Sm_2O_3. The separation of Al-Sm(density 2.3 g/cm^3) product melt from the BMFS melt is achieved by controlling the BMFS density to less than 2.0 g/cm3. It is concluded that the optimal operation conditions to control the BMFS molten salt density to less than 2.0 g/cm^3 are:maintain addition of Al_2O_3+Sm_2 O_3(w_((Al2O3))+w_((Sm2O3))〈9% of Na_3AlF_6,Al_2O_3/Sm_2O_3 ratio(w_((Al2O3)):w_((Sm2O3)))〉 7:3, and temperature between 965 and 995 ℃.
Samarium(Sm) has been widely used in making aluminum(Al)-Sm magnet alloy materials. The research team for this study developed a molten salt electrolyte system which directly produces AI-Sm alloy to replace the energy intensive conventional distillation technology. In this study, molten melt density was measured and operation conditions were optimized to separate AI-Sm alloy product from the fluoride molten melt electrolysis media based on density differences, Archimedes' principle was applied to measure density for the basic molten fluoride system(BMFS: Na_3 AlF_6-AlF_3-LiF-MgF_2)electrolysis media in the temperature range from 905 to 1055 ℃.The impact of temperature(t) and the Al_2O_3 and Sm_2O_3 addition ratio(w_((Al2O3)),w_((Sm2O3)) in the basic fluoride system on molten melt density was examined. The fluoride molten melt density relationship was determined to be:ρ=3.11701-0.00802 w_((Al2O3))+0.027825 w_((Sm2O3))-0.00117 t. The test results showed that molten density decreases with increase in temperature and Al_2O_3 addition ratio, and increases with the addition of Sm_2O_3, and/or Al_2O_3+Sm_2O_3. The separation of Al-Sm(density 2.3 g/cm^3) product melt from the BMFS melt is achieved by controlling the BMFS density to less than 2.0 g/cm3. It is concluded that the optimal operation conditions to control the BMFS molten salt density to less than 2.0 g/cm^3 are:maintain addition of Al_2O_3+Sm_2 O_3(w_((Al2O3))+w_((Sm2O3))〈9% of Na_3AlF_6,Al_2O_3/Sm_2O_3 ratio(w_((Al2O3)):w_((Sm2O3)))〉 7:3, and temperature between 965 and 995 ℃.
基金
Project supported by the National Natural Science Foundation of China(51564015,51674126)
Graduate Student Innovation Special Fund of Jiangxi Province(YC2015-B064)
Science and Technology Research Project of Jiangxi Department of Education(GJJ150664)
Outstanding doctoral dissertation project fund of JXUST(YB2016007)
Scientific Research Fund of JXUST(NSFJ2014-G09)