The high-temperature requirement for liquid iron smelting via molten oxide electrolysis presents significant challenges.This study investigates the electrochemical reduction of Fe(Ⅲ)in a novel low-temperature electro...The high-temperature requirement for liquid iron smelting via molten oxide electrolysis presents significant challenges.This study investigates the electrochemical reduction of Fe(Ⅲ)in a novel low-temperature electrolyte,Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3),utilizing cyclic voltammetry and square wave voltammetry techniques.The results show that Fe(Ⅲ)reduction occurs in two steps:Fe(Ⅲ)+e^(−)→Fe(Ⅱ),Fe(Ⅱ)+2e^(−)→Fe,and that the redox process of Fe(Ⅲ)/Fe(Ⅱ)at the tungsten electrode is an irreversible reaction controlled by diffusion.The diffusion coefficients of Fe(Ⅲ)in the molten Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3)in the temperature range of 1248–1278 K are between 1.86×10^(−6)cm^(2)/s and 1.58×10^(−4)cm^(2)/s.The diffusion activation energy of Fe(Ⅲ)in the molten salt is 1825.41 kJ/mol.As confirmed by XRD analysis,potentiostatic electrolysis at−0.857 V(vs.O_(2)/O_(complex)^(2-))for 6 h produces metallic iron on the cathode.展开更多
This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction betwee...This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction between various structural materials and molten salts.The apparatus enables accurate detection of every phase change during hightemperature experiments,including strong reaction processes like corrosion.Molten salts,such as chlorides or fluo⁃rides,together with the structure materials,are inserted into either quartz or boron nitride capillaries,where X-ray diffraction pattern can be continuously collected,as the samples are heated to high temperature.The replacement re⁃action,when molten ZnCl2 are etching Ti3AlC2,can be clearly observed through changes in diffraction peak intensity as well as expansion in c-axis lattice parameter of the hexagonal matrix,due to the larger atomic number and ionic ra⁃dius of Zn2+.Furthermore,we investigated the high-temperature corrosion process when GH3535 alloy is in FLiNaK molten salt,and can help to optimize its stability for potential applications in molten salt reactor.Additionally,this high temperature apparatus is fully compatible with the combined usage of X-ray diffraction and Raman technique,providing both bulk and surface structural information.This high temperature apparatus has been open to users and is extensively used at BL14B1 beamline of the Shanghai Synchrotron Radiation Facility.展开更多
The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na<sub>2</sub>CO<sub>3</sub>−NaCl molten salt used for Sb smelting was investigated in the tempera...The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na<sub>2</sub>CO<sub>3</sub>−NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 ºC. The saturated amount of dissolved ZnO in the molten salt remained constant at 0.02% and was unaffected by temperature; additionally, ZnO did not react with the molten salt. In contrast, the saturated amount of dissolved ZnS in the eutectic molten salt increased with increasing temperature, and the content of ZnS was 0.53% at 1000 ºC. In addition, ZnS reacted with Na<sub>2</sub>CO<sub>3</sub> above 900 ºC to give ZnO. The sedimentation rates of these three species in the molten salt followed the order of Sb>ZnS>ZnO. It was thus concluded that ZnO is an appropriate sulfur-fixing agent for low-temperature Sb smelting in a Na<sub>2</sub>CO<sub>3</sub>−NaCl molten medium, and that the optimal smelting temperature is below 900 ºC.展开更多
We report here the top-seeded solution growth of KTiOPO_(4)crystals from the K_(2)O-P_(2)O_(5)-TiO_(2)-WO_(3) system.KTiOPO_(4) crystallizes as the single stable phase over the ternperature range 930-700℃.Growth rate...We report here the top-seeded solution growth of KTiOPO_(4)crystals from the K_(2)O-P_(2)O_(5)-TiO_(2)-WO_(3) system.KTiOPO_(4) crystallizes as the single stable phase over the ternperature range 930-700℃.Growth rates up to 0.9mm/d could be used to grow optical quality crystals.展开更多
高炉铁口铁水温度场(Molten iron temperature field,MITF)是表征铁水质量、判断炉温状况的重要信息.然而高炉出铁场动态粉尘的干扰使得铁水温度场的在线准确获取充满挑战.为此,首次提出基于红外与可见光视觉的高炉铁口铁水温度场检测方...高炉铁口铁水温度场(Molten iron temperature field,MITF)是表征铁水质量、判断炉温状况的重要信息.然而高炉出铁场动态粉尘的干扰使得铁水温度场的在线准确获取充满挑战.为此,首次提出基于红外与可见光视觉的高炉铁口铁水温度场检测方法,利用可见光图像为红外视觉测温提供先验粉尘干扰情况.首先,设计红外与可见光视觉协同的测温系统,同步获取高炉铁口铁水流的红外图像和可见光图像,铁水流红外图像表征铁水原始温度场信息,可见光图像为量化粉尘透射率提供数据基础.其次,构建基于色彩一致性的可见光图像中粉尘透射率估计模型和基于雾线先验的红外图像中粉尘透射率估计模型,得到红外波段下粉尘透射率.最后,结合红外辐射测温原理,构建基于粉尘透射率的红外测温近似补偿模型,实现铁水温度场的针对性补偿,获取误差较小的铁水温度.工业实验表明,相比于仅利用红外视觉测量铁水温度场,所提方法能够显著降低粉尘造成的测温误差,为高炉调控提供连续可靠的铁水温度数据.展开更多
基金Project(52074084)supported by the National Natural Science Foundation of China。
文摘The high-temperature requirement for liquid iron smelting via molten oxide electrolysis presents significant challenges.This study investigates the electrochemical reduction of Fe(Ⅲ)in a novel low-temperature electrolyte,Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3),utilizing cyclic voltammetry and square wave voltammetry techniques.The results show that Fe(Ⅲ)reduction occurs in two steps:Fe(Ⅲ)+e^(−)→Fe(Ⅱ),Fe(Ⅱ)+2e^(−)→Fe,and that the redox process of Fe(Ⅲ)/Fe(Ⅱ)at the tungsten electrode is an irreversible reaction controlled by diffusion.The diffusion coefficients of Fe(Ⅲ)in the molten Na_(2)SiO_(3)-SiO_(2)-Fe_(2)O_(3)in the temperature range of 1248–1278 K are between 1.86×10^(−6)cm^(2)/s and 1.58×10^(−4)cm^(2)/s.The diffusion activation energy of Fe(Ⅲ)in the molten salt is 1825.41 kJ/mol.As confirmed by XRD analysis,potentiostatic electrolysis at−0.857 V(vs.O_(2)/O_(complex)^(2-))for 6 h produces metallic iron on the cathode.
基金CAS Photon Science Research Center for Carbon DioxideCAS President’s International Fellowship Initiative(2024PVA0097)+1 种基金National Key Research and Development Program of China(2017YFA0403000,2017YFA0402800)National Natural Science Foundation of China(U1932201,U1732121)。
文摘This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction between various structural materials and molten salts.The apparatus enables accurate detection of every phase change during hightemperature experiments,including strong reaction processes like corrosion.Molten salts,such as chlorides or fluo⁃rides,together with the structure materials,are inserted into either quartz or boron nitride capillaries,where X-ray diffraction pattern can be continuously collected,as the samples are heated to high temperature.The replacement re⁃action,when molten ZnCl2 are etching Ti3AlC2,can be clearly observed through changes in diffraction peak intensity as well as expansion in c-axis lattice parameter of the hexagonal matrix,due to the larger atomic number and ionic ra⁃dius of Zn2+.Furthermore,we investigated the high-temperature corrosion process when GH3535 alloy is in FLiNaK molten salt,and can help to optimize its stability for potential applications in molten salt reactor.Additionally,this high temperature apparatus is fully compatible with the combined usage of X-ray diffraction and Raman technique,providing both bulk and surface structural information.This high temperature apparatus has been open to users and is extensively used at BL14B1 beamline of the Shanghai Synchrotron Radiation Facility.
基金Projects(51104128,51234009)supported by the National Natural Science Foundation of China
文摘The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na<sub>2</sub>CO<sub>3</sub>−NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 ºC. The saturated amount of dissolved ZnO in the molten salt remained constant at 0.02% and was unaffected by temperature; additionally, ZnO did not react with the molten salt. In contrast, the saturated amount of dissolved ZnS in the eutectic molten salt increased with increasing temperature, and the content of ZnS was 0.53% at 1000 ºC. In addition, ZnS reacted with Na<sub>2</sub>CO<sub>3</sub> above 900 ºC to give ZnO. The sedimentation rates of these three species in the molten salt followed the order of Sb>ZnS>ZnO. It was thus concluded that ZnO is an appropriate sulfur-fixing agent for low-temperature Sb smelting in a Na<sub>2</sub>CO<sub>3</sub>−NaCl molten medium, and that the optimal smelting temperature is below 900 ºC.
文摘We report here the top-seeded solution growth of KTiOPO_(4)crystals from the K_(2)O-P_(2)O_(5)-TiO_(2)-WO_(3) system.KTiOPO_(4) crystallizes as the single stable phase over the ternperature range 930-700℃.Growth rates up to 0.9mm/d could be used to grow optical quality crystals.
文摘高炉铁口铁水温度场(Molten iron temperature field,MITF)是表征铁水质量、判断炉温状况的重要信息.然而高炉出铁场动态粉尘的干扰使得铁水温度场的在线准确获取充满挑战.为此,首次提出基于红外与可见光视觉的高炉铁口铁水温度场检测方法,利用可见光图像为红外视觉测温提供先验粉尘干扰情况.首先,设计红外与可见光视觉协同的测温系统,同步获取高炉铁口铁水流的红外图像和可见光图像,铁水流红外图像表征铁水原始温度场信息,可见光图像为量化粉尘透射率提供数据基础.其次,构建基于色彩一致性的可见光图像中粉尘透射率估计模型和基于雾线先验的红外图像中粉尘透射率估计模型,得到红外波段下粉尘透射率.最后,结合红外辐射测温原理,构建基于粉尘透射率的红外测温近似补偿模型,实现铁水温度场的针对性补偿,获取误差较小的铁水温度.工业实验表明,相比于仅利用红外视觉测量铁水温度场,所提方法能够显著降低粉尘造成的测温误差,为高炉调控提供连续可靠的铁水温度数据.
