The direct electrochemical synthesis of metal alkoxides [Ti（OEt）4, Ti（OPr-i）4, Ti（OBu）4, Ti（OEt）2（acac）, Cu（OEt）2, Cu（OBu）2, Mg（OEt）2 and Ni（OEt）2] were studied by anode dissolution of metals in abso...The direct electrochemical synthesis of metal alkoxides [Ti（OEt）4, Ti（OPr-i）4, Ti（OBu）4, Ti（OEt）2（acac）, Cu（OEt）2, Cu（OBu）2, Mg（OEt）2 and Ni（OEt）2] were studied by anode dissolution of metals in absolute ethanol in the presence of a conductive additives. The anodic behaviour of Ti electrode in ethanol was investigated by using cyclic voltammetry（CV）. These metal alkoxides were characterized by FTIR spectra. The results show that direct electrochemical synthesis of metal alkoxides have a high current efficiency and electrolysis yield. These alkoxides have a high purity and can be directly used as the precursor of nanosize oxides prepared by sol-gel procedure. The anodic behaviour of Ti electrode in alcohol is markedly the feature of the pitting corrosion. The passivation of Ti anode would occur in the presence of trace water.展开更多
Cyclic voltammetric behavior of electrooxidation of Mn(Ⅱ) under ultrasound and without ultrasound were compared. With the ultrasound irradiation the reduction peak potential of Pb(Ⅳ)/ Pb(Ⅱ) was found shifted negati...Cyclic voltammetric behavior of electrooxidation of Mn(Ⅱ) under ultrasound and without ultrasound were compared. With the ultrasound irradiation the reduction peak potential of Pb(Ⅳ)/ Pb(Ⅱ) was found shifted negatively about 0.14 V, initial electrolytic potential reduced 0.2 V and reduction peak current increased. At the same conditions,the conversion of Mn(Ⅱ) was increased. The optimum conditions for electrooxidation were 0.3 mol/L solution of Mn(Ⅱ), 6 mol/L H 2SO 4, electrolysis potential 2.3 V and 44 W ultrasound.展开更多
Based on ion chromatography technology, we have developed a new method that combines ion chromatography with a conductivity detector to separate and determine the substances of oxalic acid and glyoxalic acid, which ar...Based on ion chromatography technology, we have developed a new method that combines ion chromatography with a conductivity detector to separate and determine the substances of oxalic acid and glyoxalic acid, which are the main substances in the electrosynthesis of glyoxalic acid. The experimental results demonstrate that the detection sensitivity is ahead of 10 -6 grade, the cofficient of variation of retention time, the height of peak and the area of peak outperform 1%. All the recoveries of the detected substances are ranged between 98% and 102%. The method exhibits advantages of high selectivity, sensitivity, speediness and simple equipment. Furthermore, simultaneous determination of a mixture of several substances can be carried out by the method. We have demonstrated in the current paper that the ion chromatography is a speedy, effective, new detection method, which may be used to determine the substances existing in the electrosynthesis process of glyoxalic acid.展开更多
文摘The direct electrochemical synthesis of metal alkoxides [Ti（OEt）4, Ti（OPr-i）4, Ti（OBu）4, Ti（OEt）2（acac）, Cu（OEt）2, Cu（OBu）2, Mg（OEt）2 and Ni（OEt）2] were studied by anode dissolution of metals in absolute ethanol in the presence of a conductive additives. The anodic behaviour of Ti electrode in ethanol was investigated by using cyclic voltammetry（CV）. These metal alkoxides were characterized by FTIR spectra. The results show that direct electrochemical synthesis of metal alkoxides have a high current efficiency and electrolysis yield. These alkoxides have a high purity and can be directly used as the precursor of nanosize oxides prepared by sol-gel procedure. The anodic behaviour of Ti electrode in alcohol is markedly the feature of the pitting corrosion. The passivation of Ti anode would occur in the presence of trace water.
文摘Cyclic voltammetric behavior of electrooxidation of Mn(Ⅱ) under ultrasound and without ultrasound were compared. With the ultrasound irradiation the reduction peak potential of Pb(Ⅳ)/ Pb(Ⅱ) was found shifted negatively about 0.14 V, initial electrolytic potential reduced 0.2 V and reduction peak current increased. At the same conditions,the conversion of Mn(Ⅱ) was increased. The optimum conditions for electrooxidation were 0.3 mol/L solution of Mn(Ⅱ), 6 mol/L H 2SO 4, electrolysis potential 2.3 V and 44 W ultrasound.
文摘Based on ion chromatography technology, we have developed a new method that combines ion chromatography with a conductivity detector to separate and determine the substances of oxalic acid and glyoxalic acid, which are the main substances in the electrosynthesis of glyoxalic acid. The experimental results demonstrate that the detection sensitivity is ahead of 10 -6 grade, the cofficient of variation of retention time, the height of peak and the area of peak outperform 1%. All the recoveries of the detected substances are ranged between 98% and 102%. The method exhibits advantages of high selectivity, sensitivity, speediness and simple equipment. Furthermore, simultaneous determination of a mixture of several substances can be carried out by the method. We have demonstrated in the current paper that the ion chromatography is a speedy, effective, new detection method, which may be used to determine the substances existing in the electrosynthesis process of glyoxalic acid.
