工业纯铁/盐酸体系中聚丙烯酸的缓蚀作用机理

利用稳态极化曲线测量和恒电位方波测极化阻力Rp 的方法研究了聚丙烯酸 (PAAC)在工业纯铁 / 0 .5mol·L-1HCl中的缓蚀行为及其吸附特征 .结果表明 ,PAAC作为阻滞剂参与并阻滞了铁在盐酸溶液中的阳极溶解过程 ,但对阴极过程几乎无作用 .推导了PAAC参与并阻滞铁的阳极溶解过程的动力学方程 ,提出了相应的缓蚀机理 .

CORROSION RESISTANCE MECHANISM OF POLYACRYLIC ACID FOR PURE IRON IN HCl SOLUTION

The corrosion inhibition by polyacrylic acid for industrial pure iron in HCl solution was studied by using stable state polarization curves and polarization resistance ( R p). The results show that polyacrylic acid resisted and participated in iron’s anodic dissolution process, but it was not effective on irons cathodic process. The adsorption of polyacrylic acid in lower concentrations at the iron / HCl solution interface followed Temkin isotherm equation and its inhibition efficiency was found to be of a geometric blocking effect. However the inhibition efficiency of polyacrylic acid in higher concentrations was attributed to the inhibition effect on the anodic dissolution reaction of iron. The possible model for adsorption of polyacrylic acid at the iron/HCl solution interface was established. The kinetic equation of polyacrylic acid resisting and participating in the anodic dissolution process was deduced. The possible inhibition mechanism was discussed.