应用循环伏安法研究了在乙腈和水的混合溶液中3,4,5,6-四氯-2-三氯甲基吡啶于银电极上的电化学行为及其脱氯反应.实验表明:3,4,5,6-四氯-2-三氯甲基吡啶在银电极上的电化学还原是扩散控制的不可逆过程,并有伴随后续化学反应的特征;温度对反应有促进作用.求得3,4,5,6-四氯-2-三氯甲基吡啶在乙腈和水的混合溶液(体积比5∶1)中的扩散系数D=3.0×10-5cm2/s.
The electrochemical reductive behavior of 3,4,5,6-tetrachloro-2-trichloropyridine(heptachloropyridine) on silver electrode in the mixture of acetonitrile and water solutions containing TBAP was investigated by cyclic voltammetry.The influences of scan rate,concentration and temperature on the electrochemical behavior were discussed.It was shown that the reduction of heptachloropyridine on the silver electrode was a diffusion-controlled irreversible process.The diffusion coefficient of heptachloropyridine in the acetonitrile solution was 3.0×10-5 cm2/s.The mechanism of the dechloration of 3,4,5,6-tetrachloro-2-trichloropyridine was also discussed.
[1]Sudarshan K Malhotra.Reduction of trichloromethylpyr-idines to dichloromethylpyridines:US,4499276[P].1985.
[2]James N Seiber.Electrolytic reduction of halogenatedhalomethylpyridine:US,3687827[P].1972.
[3]Leo R Morris,Midland Mich.Preparation of(dichlo-romethyl)pyridines by reductive dechlorination:US,4260766[P].1981.
[4]Wang Daquan,Ma Chun-an.Development of chinese or-ganic electrochemistry and industry[M].Beijing:Chi-na Petrochemical Press,2007.
[5]Sandra B Rondinini,Patrizia R Mussini,Federico Crip-pa,et al.Electrocatalytic potentialities of silver as acathode for organic halide reductions[J].Electrochem-istry Communications,2000,2:491-496.
[6]Sandra Rondinini,Alberto Vertova.Electrocatalysis onsilver and silver alloys for dichloromethane and trichlo-romethane dehalogenation[J].Electrochimica Acta,2004,49:4035-4046.
[7]Silvia Ardizzone,Giuseppe Cappelletti,Patrizia RomanaMussini,et al.Adsorption competition effects in theelectrocatalytic reduction of organic halides on silver[J].Journal of Electroanalytical Chemistry,2002,532:285-293.
[8]Ma Chun-an,Xu Yinghua,Zhu Yinghong,et al.Elec-trocatalytic reduction of 3,4,5,6-tetrachloropicol inicacid on roughened silver electrode[J].Journal of Zhe-jiang University of Technology,2006,34(5):473-477.
[9]Nicholson R S,Shin I.Theory of stationary electrodepolarography.Single scan and cyclic methods applied toreversible,irreversible,and kinetic systems[J].Ana-lytical Chemistry,1964,36(4):706-723.
[10]Anson F.Electrochemistry and electro analytical chem-istry[M].Beijing:Peking University Press,1981.
[11]Ma Chun-an.Introduction to synthetic organic electro-chemistry[M].Beijing:Science Press,2002.