乙腈溶剂中三氯化苄在银阴极上的脱氯反应.pdf

物理化学学报( uli Huaxue uebao)
Acta Phys. -Chim. Sin. 2013, 29(5), 973-980
73
Article
doi:10.3866/PKU. WIXB201302283
www.whxb.pku.edu.cn
乙腈溶剂中三氯化苄在银阴极上的脱氯反应
徐颖华马红星蔡倩倩朱英红马淳安
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)
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
求电极更优良的电催化活性;(2)三氯化苹在低扫描速率(の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(wsAg/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
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
中图分类号:O646
Dechlorination of Benzenyltrichloride in CH CN Solvent at a
Silver Cathode
XU Ying-hua MA Hong-xing CAL Qian-qian ZHU Ying
MA Chun-an
( State Key Laboratory Breeding Base of Green Chemistry-synthesis Technology, College ofchemical Engineering and Materials
Zhejiang University of Technology, Hangzhou 310032, Zhejiang Province, P R. China
Abstract: The reductive dechlorination mechanism of benzenyitrichloride at an Ag cathode was investigated
using cyclic voltammetry(V) and potentiostatic electrolysis, in CH CN solvent containing 0.1 mol. L
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 hii r a i activity than H for the dechlorination (2the first reduction peak,
which ws divied from the reduction peak of benzenyltrichloride at-119vvs Ag/Ag when the scan rate
was 50 mvs 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-075 to-1.75 V (Vs Ag/Ag). The electrolysis resuits indicated that
dechlorination product selectivity was strongly dependent on the Ag electrode potential
Key Words: Ag electrode; Reductive dechlorination; Dechlorination mechanism Wide anode region
CV; Adsorption of CE
1引言
理2中都有重要的应用价值.因此,该反应机理一直
肉代有机物的电还原脱卤反应是有机电化学是有机电化学家关注的焦点问题,对于惰性电极
中最重要的反应类型之一,其在有机合成'和环境处(如玻碳)上的电还原脱卤反应过程,目前已经有了
Received: January 11, 2013; Revised: February 27, 2013; Published on Web: February 28, 2013
Correspondingauthor.Emailscience(@zjut.edu.cn;Tel:+86-571-88320813
The project was supported by the National Natural Science Foundation of China(21106133 )and National Key Basic Research Program of China
(973)(2012CB722
国家自然科学基金(21106133)和国家重点基础研究发展规划项目(973)(2012CB722604)资助
C Editorial office ofacta Physico-chimica Sinica