Electrolytic reductions of oxygenic functional groups (OFGs) on coal surface and coal model compounds with OFGs in an aqueous NaCl solution are studied by electrochemical methods combined with GC/MS, GC and FFIR ana...Electrolytic reductions of oxygenic functional groups (OFGs) on coal surface and coal model compounds with OFGs in an aqueous NaCl solution are studied by electrochemical methods combined with GC/MS, GC and FFIR analyses. Different electrode reactions, their corresponding potentials and dynamic equations during the processes are investigated. The results show that benzoic acid, benzaldehyde, benzalcohol and hypnone are reduced to benzaldehyde and benzalcohol, methoxybenzene and benzal- cohol, toluene and styrene, respectively, at the cathode. The corresponding electrode potentials and dynamic equations are deter- mined. The.electrolytic reduction also leads to an increase in the contents of hydroxyl groups and aliphatic moieties and a corresponding decrease in those of carboxyl and carbonyl groups in Nantong coal, a high-sulfur coal, an enhancement in the flotation desulfurization of the coal. ER also reduces organic sulfur and FeS2 in the coal.展开更多
YbSO4 purification by an electrolytic reduction method from Tm-Yb-Lu concentrates in sulphate medium was studied, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode respectively under normal atmos...YbSO4 purification by an electrolytic reduction method from Tm-Yb-Lu concentrates in sulphate medium was studied, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode respectively under normal atmosphere without nitrogen or argon gas protection. The parameters of the electrodes, such as their areas, positions, and the distance between the anode and cathode were optimized for the electrolytic reduction process. By the optimal process, the product YbSO4 is purified to 99. 5% with recovery of 80%. Meanwhile, Lu is also concentrated into 50%, which is beneficial to its further purification.展开更多
In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride ...In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride molten salt as the reaction medium at 923 K.The study assessed the effects of lithium thermochemical reduction and electrolytic reduction of ZnO.The volatilization behavior of metal oxides in molten salts,the equivalent of a reducing agent,reduction time,amount of molten salt,stirring time,and the method of reduction feed were investigated for their impacts on the reduction yield and product composition.X-ray powder diffraction(XRD)analysis of the products showed that lithium reduction of ZnO not only produced metallic Zn but also formed a LiZn alloy.Electrolytic reduction can be used to obtain the metallic Zn product by controlling the potential below-2.2 V(vs Ag/Ag^(+)).Moreover,sintered oxides and higher electrode potentials could enhance the efficiency of electrolysis.Under the optimal reaction conditions determined experimentally,the lithium reduction experiment achieved a yield of 77.2%after a 12-h test,and the electrolytic reduction reached a yield of 85.4%after a 6-h test.展开更多
The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCl solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfur...The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCl solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfurization ratio was also studied. The electrochemical-reduction processed coal was examined by X-ray diffraction, Fourier transform infrared spectroscopy and wet chemical analysis. The results show that electrochemical reduction converts hydrophobic pyrite in Nantong coal into hydrophilic FeS and S2- and leads to an increase in the concentration of hydroxyl groups and aliphatic moieties and a corresponding decrease in carboxyl and carbonyl groups, which enhances the flotation desulfurization of the coal.展开更多
The cyclic voltammetry was used to study the electrochemical reaction of Sm(III) in NaCl-KCl equimolar mixture on the Co and Cu cathodes. It is reasonable to presume that the reduction of Sm(III) to Sm(II) was realize...The cyclic voltammetry was used to study the electrochemical reaction of Sm(III) in NaCl-KCl equimolar mixture on the Co and Cu cathodes. It is reasonable to presume that the reduction of Sm(III) to Sm(II) was realized on Co and Cu electrodes respectively at first step. Sm(II) was subject to the reduction and formed alloys with Co and Cu on the electrode surface.展开更多
This article studied the europium electroreduction kinetic properties in the Sm-Eu-Gd chloride system by using an electrolytic cell with membrane and constant potential method.The results indicate that within the para...This article studied the europium electroreduction kinetic properties in the Sm-Eu-Gd chloride system by using an electrolytic cell with membrane and constant potential method.The results indicate that within the parameter range of this study the europium reduction speed up with the increase of the system's temperature,the stirring intensity,feed concentration and the cathod area,and with the decrease of the cathodic potential.As the feed acidity increases,the reduction rate decreases.An empirical formula for europium's electroreduction kinetics in this experimental condition is also given.展开更多
The cyclic voltammetry was used to investigate the electrode processes of Nd(III) reduced on iron electrode and Nd(III),Fe(II) reduced on molybdenum electrode in molten chlorides. The Nd-Fe and Nd-rich RE-Fe alloys co...The cyclic voltammetry was used to investigate the electrode processes of Nd(III) reduced on iron electrode and Nd(III),Fe(II) reduced on molybdenum electrode in molten chlorides. The Nd-Fe and Nd-rich RE-Fe alloys contained rare earth up to 90wt% were prepared by consumable cathode and electrolytic codeposition. The mechanism of electrochemical formation of Nd-Fe alloy had been discussed.展开更多
Electrolytic reduction is a crucial process during the pyroprocessing of oxide spent fuel.This paper investigates the effects of different concentrations of Li_(2)O on the properties of the LiCl^(-)UCl_(3)-Li_(2)O mol...Electrolytic reduction is a crucial process during the pyroprocessing of oxide spent fuel.This paper investigates the effects of different concentrations of Li_(2)O on the properties of the LiCl^(-)UCl_(3)-Li_(2)O molten salt system during electrolytic reduction using first-principles molecular dynamics simulations.The study reveals that increasing Li_(2)O concentration lowers the ion diffusion coefficients of Li^(+),Cl^(-),and O^(2-)in the electrolyte,which has negative effect on the transport property of the system.A thorough analysis of the ligand structures formed by various components in the molten salt was conducted,including radial distribution functions and angular distribution functions.The analysis reveals that oxygen ions compete with chloride ions for coordination with cations.This competitive interaction has a significant impact on the coordination between Li-Cl and U-Cl elements,thereby influencing the microstructure.The analysis of electronic structures shows that the addition of Li_(2)O affects the charge transfer among lithium,uranium,and chlorine,impacting the bond strength between anions and cations.Finally,the calculation of redox potential shows that an appropriate concentration of Li_(2)O is beneficial to the electrochemical reduction process.The research results provide a theoretical basis for the design of molten salts in the electrolytic reduction process.展开更多
基金Project 2004CB217601 supported by the Special Fund for Major State Basic Research Projects
文摘Electrolytic reductions of oxygenic functional groups (OFGs) on coal surface and coal model compounds with OFGs in an aqueous NaCl solution are studied by electrochemical methods combined with GC/MS, GC and FFIR analyses. Different electrode reactions, their corresponding potentials and dynamic equations during the processes are investigated. The results show that benzoic acid, benzaldehyde, benzalcohol and hypnone are reduced to benzaldehyde and benzalcohol, methoxybenzene and benzal- cohol, toluene and styrene, respectively, at the cathode. The corresponding electrode potentials and dynamic equations are deter- mined. The.electrolytic reduction also leads to an increase in the contents of hydroxyl groups and aliphatic moieties and a corresponding decrease in those of carboxyl and carbonyl groups in Nantong coal, a high-sulfur coal, an enhancement in the flotation desulfurization of the coal. ER also reduces organic sulfur and FeS2 in the coal.
文摘YbSO4 purification by an electrolytic reduction method from Tm-Yb-Lu concentrates in sulphate medium was studied, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode respectively under normal atmosphere without nitrogen or argon gas protection. The parameters of the electrodes, such as their areas, positions, and the distance between the anode and cathode were optimized for the electrolytic reduction process. By the optimal process, the product YbSO4 is purified to 99. 5% with recovery of 80%. Meanwhile, Lu is also concentrated into 50%, which is beneficial to its further purification.
文摘In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride molten salt as the reaction medium at 923 K.The study assessed the effects of lithium thermochemical reduction and electrolytic reduction of ZnO.The volatilization behavior of metal oxides in molten salts,the equivalent of a reducing agent,reduction time,amount of molten salt,stirring time,and the method of reduction feed were investigated for their impacts on the reduction yield and product composition.X-ray powder diffraction(XRD)analysis of the products showed that lithium reduction of ZnO not only produced metallic Zn but also formed a LiZn alloy.Electrolytic reduction can be used to obtain the metallic Zn product by controlling the potential below-2.2 V(vs Ag/Ag^(+)).Moreover,sintered oxides and higher electrode potentials could enhance the efficiency of electrolysis.Under the optimal reaction conditions determined experimentally,the lithium reduction experiment achieved a yield of 77.2%after a 12-h test,and the electrolytic reduction reached a yield of 85.4%after a 6-h test.
基金supported by the Special Fund for Major State Basic Research Program of China (Project 2004CB217601).
文摘The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCl solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfurization ratio was also studied. The electrochemical-reduction processed coal was examined by X-ray diffraction, Fourier transform infrared spectroscopy and wet chemical analysis. The results show that electrochemical reduction converts hydrophobic pyrite in Nantong coal into hydrophilic FeS and S2- and leads to an increase in the concentration of hydroxyl groups and aliphatic moieties and a corresponding decrease in carboxyl and carbonyl groups, which enhances the flotation desulfurization of the coal.
文摘The cyclic voltammetry was used to study the electrochemical reaction of Sm(III) in NaCl-KCl equimolar mixture on the Co and Cu cathodes. It is reasonable to presume that the reduction of Sm(III) to Sm(II) was realized on Co and Cu electrodes respectively at first step. Sm(II) was subject to the reduction and formed alloys with Co and Cu on the electrode surface.
基金The project was supported by the National Natural Science Foundation of China
文摘This article studied the europium electroreduction kinetic properties in the Sm-Eu-Gd chloride system by using an electrolytic cell with membrane and constant potential method.The results indicate that within the parameter range of this study the europium reduction speed up with the increase of the system's temperature,the stirring intensity,feed concentration and the cathod area,and with the decrease of the cathodic potential.As the feed acidity increases,the reduction rate decreases.An empirical formula for europium's electroreduction kinetics in this experimental condition is also given.
基金supported by the Ministry of Science and Technology of China(Nos.2016YFA0204100 and 2016YFA0200200)the National Natural Science Foundation of China(Nos.21321002,21573220 and 21303191)the strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA09030100)
基金Project supported by the Science Fund of the Chinese Academy of Sciences.
文摘The cyclic voltammetry was used to investigate the electrode processes of Nd(III) reduced on iron electrode and Nd(III),Fe(II) reduced on molybdenum electrode in molten chlorides. The Nd-Fe and Nd-rich RE-Fe alloys contained rare earth up to 90wt% were prepared by consumable cathode and electrolytic codeposition. The mechanism of electrochemical formation of Nd-Fe alloy had been discussed.
基金financial support provided by the National Natural Science Foundation of China(22476130 and 12205190)。
文摘Electrolytic reduction is a crucial process during the pyroprocessing of oxide spent fuel.This paper investigates the effects of different concentrations of Li_(2)O on the properties of the LiCl^(-)UCl_(3)-Li_(2)O molten salt system during electrolytic reduction using first-principles molecular dynamics simulations.The study reveals that increasing Li_(2)O concentration lowers the ion diffusion coefficients of Li^(+),Cl^(-),and O^(2-)in the electrolyte,which has negative effect on the transport property of the system.A thorough analysis of the ligand structures formed by various components in the molten salt was conducted,including radial distribution functions and angular distribution functions.The analysis reveals that oxygen ions compete with chloride ions for coordination with cations.This competitive interaction has a significant impact on the coordination between Li-Cl and U-Cl elements,thereby influencing the microstructure.The analysis of electronic structures shows that the addition of Li_(2)O affects the charge transfer among lithium,uranium,and chlorine,impacting the bond strength between anions and cations.Finally,the calculation of redox potential shows that an appropriate concentration of Li_(2)O is beneficial to the electrochemical reduction process.The research results provide a theoretical basis for the design of molten salts in the electrolytic reduction process.