乙腈溶剂中三氯化苄在银阴极上的脱氯反应  

Dechlorination of Benzenyltrichloride in CH_3CN Solvent at a Silver Cathode

作　　者：徐颖华[1] 马红星[1] 蔡倩倩[1] 朱英红[1] 马淳安[1] 

机构地区：[1]浙江工业大学化学工程与材料学院,绿色化学合成技术国家重点实验室培养基地,杭州310032

出　　处：《物理化学学报》2013年第5期973-980,共8页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(21106133);国家重点基础研究发展规划项目(973)(2012CB722604)资助~~

摘　　要：用常规循环伏安(CV)法和恒电位电解法研究了含0.1mol·L-1四丁基高氯酸铵(TBAP)乙腈溶剂中三氯化苄在银电极上的还原脱氯机理;用以银和氯离子的氧化还原反应为基础的阳极区拓宽CV法探测了还原脱氯反应生成氯离子在银电极上的吸附情况.循环伏安实验表明:(1)银电极对三氯化苄的电还原脱氯反应具有比汞电极更优良的电催化活性;(2)三氯化苄在低扫描速率(v)下得到的第一个还原峰对应反应受吸附控制,电子转移系数约为0.25,遵守协同电子转移机理;(3)三氯化苄还原脱氯反应生成氯离子在银电极上的吸附电位为-0.75--1.75V(vsAg/Ag+).电解实验表明,通过改变银电极电位可以有效控制三氯化苄还原反应的电解产物.The reductive dechlorination mechanism of benzenyltrichloride at an Ag cathode was investigated using cyclic voltammetry （CV） and potentiostatic electrolysis, in CH3CN solvent containing 0.1 mol·L^-1 tetrabutylammonium perchlorate （TBAP）. The adsorption of CI- generated during dechlorination was detected using wide anode region CV, based on its anodic reaction with Ag. The CV results indicated that： （1） Ag exhibited better etectrocatalytic activity than Hg for the dechlorination; （2） the first reduction peak, which was divided from the reduction peak of benzenyltrichloride at -1.19 V （vs Ag/Ag＊） when the scan rate was -〈50 mV·s^-1, is an adsorption controlled process and its electron transfer occurred in a concerted way, and the electron transfer coefficient is approximately 0.25; （3） the potential region where departing CI- adsorbed on Ag ranged from-0.75 to-1.75 V （vs Ag/Ag＋ ）. The electrolysis results indicated that dechlorination product selectivity was strongly dependent on the Ag electrode potential.

关 键 词：银电极 还原脱氯 脱氯机理 阳极区拓宽的循环伏安法 氯离子吸附 

分 类 号：O646.54[理学—物理化学]