磷酸溶液中DDA在锌表面的吸附及其缓蚀作用

Adsorption of DDA in Phosphoric Acid Solution on Zinc Surface and Its Corrosion Inhibition

采用失重法及电化学法研究了锌在含或不含十二烷基胺(DDA)的磷酸溶液中的腐蚀作用,得出相应的动力学方程,求得有关的动力学及热力学参数.用光电子能谱(XPS)检测发现,在40～70℃区间,锌在磷酸溶液中生成Zn(OH)x覆盖层,表现出较强的自缓蚀效果,而在30～40℃区间,因DDA以及HPO42-,H2PO4-等微粒同时吸附在锌表面,DDA在磷酸溶液中表现出较强的缓蚀作用.用吸附理论讨论了这种缓蚀作用产生的原因.

The weight-loss and electrochemica l me thods were used to investigate th e corrosion behavior of metallic zinc in phos phoric acid sol utions with or without dodecyl amine(DDA).The corrosion rate expressions were formulated and the correspondi ng kinetic parameters and thermo dyn amic constants were calculated.Fro m the results of electron spectroscop y for chemical analysis(XPS),it was found that,over the temperature range of 40～70℃,zinc showed good self corrosion inhibition due to the coverage of Zn(OH) x produced.On the other hand,in the temperature range of 30 ～40℃,since DDA-H 3 PO 4 and several other compounds were adsorbed on zinc surface,DDA exhibited pow erfu l corrosion inhibition.The mechani sm for corrosion inhibition was dis-cu ssed by the adsorption theory.