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
Electrochemical oxidation of hydroquinone（1a） has been studied in the presence of 6-methyl-2-thiouracil（3a） and 6-propyl-2-thiouracil（3b） as nucleophiles in a DMF/buffer mixture,using cyclic voltammetry and cont...Electrochemical oxidation of hydroquinone（1a） has been studied in the presence of 6-methyl-2-thiouracil（3a） and 6-propyl-2-thiouracil（3b） as nucleophiles in a DMF/buffer mixture,using cyclic voltammetry and controlled-potential coulometry.The results indicated that the p-quinone（2a） derived from 1a participates in a 1 4-Michael addition reaction with the thiouracil derivatives（3a–b） to form the corresponding hydroquinonethioether derivatives（6a–6b）.The electrosynthesis of these compounds（6a–b） has been successfully performed on carbon rod electrodes in an undivided cell in good yield and purity.展开更多
The electrochemical oxidation of chlorimuron-ethyl on metry. The electrochemical behaviour of the electrode in a sodium Ti/SnO2-Sb2O5/PbO2 electrode was studied by cyclic voltamsulfate solution and in the mixture solu...The electrochemical oxidation of chlorimuron-ethyl on metry. The electrochemical behaviour of the electrode in a sodium Ti/SnO2-Sb2O5/PbO2 electrode was studied by cyclic voltamsulfate solution and in the mixture solution of sodium sulfate and chlorimuron-ethyl was studied. The experimental results of cyclic voltammetry show that the acidic medium was suitable for the efficient electrochemical oxidation of chlorimuron-ethyl. Some electro-generated reagent was formed in the electrolysis process and chlorimuron-ethyl could be oxidized by the electro-generated reagent. A Ti/SnO2-Sb2O5/PbO2 electrode was used as the anode and the electrolysis experiment was carried out under the optimized conditions. The electrolysis process was monitored by UV-Vis spectrometry and high performance liquid chromatography（HPLC）, and the chemical oxygen demand（COD） was determined by the potassium dichromate method. The mechanism of chlorimuron-ethyl to be oxided was studied primarily by the cyclic voltammetry and UV-Vis spectrometry. The results of electrolysis experiment demonstrate the possibility of the electrode to be used as an anode for the electrochemical treatment of chlorimuron-ethyl contained in waste water.展开更多
Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath in the presence of fine MgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of m...Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath in the presence of fine MgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of methanol and ethanol in alkaline medium was investigated and compared with that of carbon coated pure Ni （Ni/C）. The chemical composition, phase structure, and surface morphology of the deposited nano‐composites were studied by energy dispersive X‐ray spectros‐copy, X‐ray diffractometry, and scanning electron microscopy, respectively. Different electrochemi‐cal techniques were used to estimate the catalytic activity of the prepared electrocatalyst anodes, including cyclic voltammetry （CV）, chronoamperometry, and electrochemical impedance spectros‐copy （EIS）. The Ni/C electrocatalyst alone exhibited remarkably low catalytic activity and poor stability toward the electrooxidation process. The inclusion of MgO significantly promoted the cata‐lytic activity of the Ni catalyst for the alcohol electrooxidation and enhanced its poisoning re‐sistance. The EIS results confirmed those of CV and revealed a lower charge transfer resistance and enhanced roughness for the Ni–MgO/C nano‐composite electrodes compared with those of Ni/C.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Semnan University Research Council for financial supports of this work
文摘Electrochemical oxidation of hydroquinone（1a） has been studied in the presence of 6-methyl-2-thiouracil（3a） and 6-propyl-2-thiouracil（3b） as nucleophiles in a DMF/buffer mixture,using cyclic voltammetry and controlled-potential coulometry.The results indicated that the p-quinone（2a） derived from 1a participates in a 1 4-Michael addition reaction with the thiouracil derivatives（3a–b） to form the corresponding hydroquinonethioether derivatives（6a–6b）.The electrosynthesis of these compounds（6a–b） has been successfully performed on carbon rod electrodes in an undivided cell in good yield and purity.
基金Supported by the Science and Technology Foundation of the Education Department of Liaoning Province,China (No.2009A557)
文摘The electrochemical oxidation of chlorimuron-ethyl on metry. The electrochemical behaviour of the electrode in a sodium Ti/SnO2-Sb2O5/PbO2 electrode was studied by cyclic voltamsulfate solution and in the mixture solution of sodium sulfate and chlorimuron-ethyl was studied. The experimental results of cyclic voltammetry show that the acidic medium was suitable for the efficient electrochemical oxidation of chlorimuron-ethyl. Some electro-generated reagent was formed in the electrolysis process and chlorimuron-ethyl could be oxidized by the electro-generated reagent. A Ti/SnO2-Sb2O5/PbO2 electrode was used as the anode and the electrolysis experiment was carried out under the optimized conditions. The electrolysis process was monitored by UV-Vis spectrometry and high performance liquid chromatography（HPLC）, and the chemical oxygen demand（COD） was determined by the potassium dichromate method. The mechanism of chlorimuron-ethyl to be oxided was studied primarily by the cyclic voltammetry and UV-Vis spectrometry. The results of electrolysis experiment demonstrate the possibility of the electrode to be used as an anode for the electrochemical treatment of chlorimuron-ethyl contained in waste water.
文摘Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath in the presence of fine MgO reinforcement particles. Their performance as electrocata‐lysts for the oxidation of methanol and ethanol in alkaline medium was investigated and compared with that of carbon coated pure Ni （Ni/C）. The chemical composition, phase structure, and surface morphology of the deposited nano‐composites were studied by energy dispersive X‐ray spectros‐copy, X‐ray diffractometry, and scanning electron microscopy, respectively. Different electrochemi‐cal techniques were used to estimate the catalytic activity of the prepared electrocatalyst anodes, including cyclic voltammetry （CV）, chronoamperometry, and electrochemical impedance spectros‐copy （EIS）. The Ni/C electrocatalyst alone exhibited remarkably low catalytic activity and poor stability toward the electrooxidation process. The inclusion of MgO significantly promoted the cata‐lytic activity of the Ni catalyst for the alcohol electrooxidation and enhanced its poisoning re‐sistance. The EIS results confirmed those of CV and revealed a lower charge transfer resistance and enhanced roughness for the Ni–MgO/C nano‐composite electrodes compared with those of Ni/C.
