针对不加Ce和添加Ce的Fe-4%Si合金,采用NETZSCH STA 449C型综合热分析仪测定其示差扫描量热(DSC)曲线,探讨添加Ce对Fe-4%Si合金近平衡凝固过程中特征温度的影响。利用液态金属冷却(LMC)定向凝固技术,对添加Ce的Fe-4%Si合金试样通过定向...针对不加Ce和添加Ce的Fe-4%Si合金,采用NETZSCH STA 449C型综合热分析仪测定其示差扫描量热(DSC)曲线,探讨添加Ce对Fe-4%Si合金近平衡凝固过程中特征温度的影响。利用液态金属冷却(LMC)定向凝固技术,对添加Ce的Fe-4%Si合金试样通过定向凝固实验保留固-液界面。采用岛津EPMA-1720H电子探针(EPMA),对添加Ce的Fe-4%Si合金定向凝固样品,进行长时间点定量分析,探索Ce在固-液界面处的富集。结果表明,添加Ce使Fe-4%Si合金近平衡凝固过程中液相线温度和固相线温度都有降低的趋势、结晶温度区间有增大的趋势。EPMA长时间点定量分析,证实了凝固过程中Ce能够以原子或夹杂物形式在固-液界面前沿的液相富集。界面处Ce的富集,可能阻碍凝固生长过程中原子的供应,进而影响Fe-4%Si合金的近平衡凝固特征温度及结晶温度区间。展开更多
To remove the fluoride in zinc sulfate electrolyte to an appropriate level,mitigate environmental fluoride pollution,and drive the development of the hydrometallurgy industry of zinc,a novel Fe_(3)O_(4)@SiO_(2)@Fe-MIL...To remove the fluoride in zinc sulfate electrolyte to an appropriate level,mitigate environmental fluoride pollution,and drive the development of the hydrometallurgy industry of zinc,a novel Fe_(3)O_(4)@SiO_(2)@Fe-MIL-101 magnetic composite material was successfully synthesized via the one-pot method.Preparation conditions were optimized and structural characterization of this material conducted using FTIR,SEM,EDS,XRD and Hysteresis analysis.The results show that this composite exhibits a more rapid fluoride adsorption dynamics and a higher fluoride adsorption capacity(18.34 mg/g)and its adsorption behavior fitted for the first order dynamic model and the Freundlich isotherm model.The adsorption of fluorine by this composite is mainly physical adsorption according to the mean adsorption energy(1.216 kJ/mol).The interfering ions co-existed in fluoride-containing solutions,like HCO_(3)^(-),NO^(-)and Cl^(-),have a significant effect on fluorine adsorption.This composite has also been proved with magnetism,higher adsorption selectivity and satisfactory reusability.When this composite is employed as an adsorbent for adsorption removing fluoride in zinc sulfate electrolyte,it exhibits higher pH-dependent behavior as well as high fluoride removal efficiency at pH 6.5.展开更多
文摘针对不加Ce和添加Ce的Fe-4%Si合金,采用NETZSCH STA 449C型综合热分析仪测定其示差扫描量热(DSC)曲线,探讨添加Ce对Fe-4%Si合金近平衡凝固过程中特征温度的影响。利用液态金属冷却(LMC)定向凝固技术,对添加Ce的Fe-4%Si合金试样通过定向凝固实验保留固-液界面。采用岛津EPMA-1720H电子探针(EPMA),对添加Ce的Fe-4%Si合金定向凝固样品,进行长时间点定量分析,探索Ce在固-液界面处的富集。结果表明,添加Ce使Fe-4%Si合金近平衡凝固过程中液相线温度和固相线温度都有降低的趋势、结晶温度区间有增大的趋势。EPMA长时间点定量分析,证实了凝固过程中Ce能够以原子或夹杂物形式在固-液界面前沿的液相富集。界面处Ce的富集,可能阻碍凝固生长过程中原子的供应,进而影响Fe-4%Si合金的近平衡凝固特征温度及结晶温度区间。
基金National Natural Science Foundation of China(21865011)2024 Innovation and Entrepreneurship Project of College Student in Jishou University(JDCX20241122)。
文摘To remove the fluoride in zinc sulfate electrolyte to an appropriate level,mitigate environmental fluoride pollution,and drive the development of the hydrometallurgy industry of zinc,a novel Fe_(3)O_(4)@SiO_(2)@Fe-MIL-101 magnetic composite material was successfully synthesized via the one-pot method.Preparation conditions were optimized and structural characterization of this material conducted using FTIR,SEM,EDS,XRD and Hysteresis analysis.The results show that this composite exhibits a more rapid fluoride adsorption dynamics and a higher fluoride adsorption capacity(18.34 mg/g)and its adsorption behavior fitted for the first order dynamic model and the Freundlich isotherm model.The adsorption of fluorine by this composite is mainly physical adsorption according to the mean adsorption energy(1.216 kJ/mol).The interfering ions co-existed in fluoride-containing solutions,like HCO_(3)^(-),NO^(-)and Cl^(-),have a significant effect on fluorine adsorption.This composite has also been proved with magnetism,higher adsorption selectivity and satisfactory reusability.When this composite is employed as an adsorbent for adsorption removing fluoride in zinc sulfate electrolyte,it exhibits higher pH-dependent behavior as well as high fluoride removal efficiency at pH 6.5.
