铁在盐酸中的缓蚀剂的两种作用类型的研究  

A STUDY ON TWO MODES OF INTERFACE INHIBITORS FORTHE CORROSION OF IRON IN HYDROCHLORIC ACID SOLUTION

作　　者：曹楚南[1] 张鸣镝[1] 林海潮[1] 

机构地区：[1]中国科学院金属腐蚀与防护研究所腐蚀科学开放实验室,沈阳110015

出　　处：《腐蚀科学与防护技术》1992年第1期1-8,共8页Corrosion Science and Protection Technology

基　　金：国家自然科学基金。

摘　　要：通过腐蚀电位、极化曲线与交流阻抗测量研究了3种伯胺和丙炔醇对铁在盐酸中的缓蚀作用类型。结果表明,3种伯胺的缓蚀作用是几何覆盖效应,而丙炔醇的缓蚀作用则来自负催化效应。还证明,在强阳极极化的 Tafel 直线区间,十二烷胺吸附在电极表面的覆盖率θ不随电位改变,十四烷胺的θ随电位的升高而增大。丙炔醇使铁阳极溶解反应活化能位垒增高的量.fa(θ)随电位升高而减小,其数值为 df_a(θ)/dE=-73J·mol_-1.mV-1。For interface inhibitors in acid solutions,the inhibition may be divided into two modes, namely,that caused by geometrical blocking effect and that caused by negative catalytic effect.It can de- duced that for the former,ΔE_(corr),the difference between corrosion potentials of the metal in solutions with and without inhibitor,is nearly zero and the inhibition efficiency is proportional to the relative coverage esti- mated by interracial capacitance measurements,while for the latter,usually ΔE_(corr) is marked and the inhibi- tion efficiency cannot be proportional to the relative coverage.It was found that for iron in 1mol/l HCl. the inhibition was attributed to geometrical blocking effect for primary aliphatic amines and to negative catalytic effect for propargyl alcohol.In strong anodic polarization region where the Tafel law is followed, the coverage of adsorbed species does not change with electrode potential E for dodecyl amine while is in- creasing with the raising of E for tetradecyl amine.For propargyl alcohol as inhibitor for iron in HCl,the activation energy barrier of anodic dissolution of iron is decreasing with the raising of E with a value of ca.-73J·mol^(-1)·mV^(-1).

关 键 词：缓蚀剂 酸 铁 阻抗 吸附 

分 类 号：TG174.42[金属学及工艺—金属表面处理]