The Application Of Lead And Lead Alloy Electrode For Organic Electrochemical Synthesis

The development history and present situation of research of lead alloy and application of lead alloy electrode for organic electrochemical synthesis were reviewed in this paper.In the point of metallurgy and electrochemical principles,experimental alloys were designed,then the electrochemical performances, hardness properties and corrosion behavior were studied systematically through different types of techniques such as electrochemical measurement techniques,hardness test and meltallograph analysis.The results of hardness test show that the addition of metal can improve the hardness. The alloy has the best effect on improving lead alloy hardness when adding of rare earth. In comparison with pure lead electrode, the corrosion resistance of the as-prepared lead alloys are improved too,among which the Pb-Ca-Sn-Al-Cd lead alloy electrode has the best performances.The results of electrochemical test show that the lead alloys of overpotential of hydrogen evolution increase after addition of Cd,but decreases with adding of rare earth. The performances of electroreduction oxalic acid and hydrogen evolution overpotential on Pb-Ca-Sn-Al-Cd lead alloy electrode is better than those of other as-prepared lead alloys electrode. 3* lead alloy electrode(Cd content is 0. 5%) has the best performances of among all studied electrode. The kinetic parameters and apparent activation energytested at 3# lead alloy electrode are showed below: (1) in oxalic acid system: i01 =0.453 mA/cm2, W10 =14.168 kJ/mol, (2) in sulfuric acid system.i20 =5.92 10-6 mA/cm2, W20 =38.542 kJ/mol.Finally,oxalic acid is electroreduced on both 3# lead electrode and pure lead electrode,the current efficiency is up to 84. 5% and 79. 5%, respectively.Our works show that the application of Pb-Ca-Sn-Al-Cd lead alloy to organic synthesis exhibits the merits of high current efficiency and hydrogen overpotential, excellent corrosion resistance and hardness. Therefore, Pb-Ca-Sn-Al-Cd lead alloy will be a good electrode materiel for organic electrochemical synthesis.