摘要
目的研究废酸液中介质离子对曼尼希碱酸化缓蚀剂缓蚀性能的影响,以解决碳钢在酸液中的腐蚀问题。方法采用静态失重法、极化曲线、扫描电镜及能谱分析法,研究SO2-4,PO3-4对曼尼希碱型酸化缓蚀剂缓蚀性能的影响,并探究其作用机理。结果在10%(质量分数)盐酸、0.1%(质量分数)曼尼希碱的缓蚀介质中,随SO2-4质量分数的增大,腐蚀电流密度由2.81μA/cm2增加至7.32μA/cm2,腐蚀速率显著增大,缓蚀效果变弱;随PO3-4质量分数的增加,腐蚀电流密度由2.81μA/cm2减小至2.41μA/cm2,腐蚀速率减小,缓蚀效果变强。结论 SO2-4会通过钢铁表面已经形成的吸附膜上的细孔和缺陷渗入膜内,使膜发生开裂,从而侵蚀和破坏已经形成的吸附膜,抑制缓蚀剂的缓蚀效果;PO3-4与腐蚀产物Fe3+络合并在钢材表面形成一层致密的保护层,使缓蚀剂形成的吸附膜更加致密,阻止腐蚀性介质与金属表面接触,同时增加对离子或溶解氧的扩散阻力,提高缓蚀剂的缓蚀效果。
Objective To explore the effects of SO42- and PO43- on the performance of mannich base hydrochloric acid corrosion inhibitor. Methods Using static weight-loss method,polarization curve,scanning electron microscope and energy spectrum analysis,the effects of SO42-and PO43-on the performance of mannich base hydrochloric acid corrosion inhibitor were studied and its mechanism was explored. Results In corrosion medium with 10% HCl and 0. 1% mannich base,with the increase of SO42-mass fraction,the corrosion current density increased from 2. 81 μA / cm2 to 7. 32 μA / cm2,the corrosion rate significantly increased and the corrosion inhibition effect was weakened; on the contrary,with the increase of PO43-mass fraction,the corrosion current density decreased from 2. 81 μA / cm2 to 2. 41 μA / cm2,the corrosion rate decreased and the corrosion inhibition effect was strengthened.Conclusion SO42-penetrated into the steel surface adsorption film through the holes and defects,forming cracks in the film,leading to erosion and damage of the adsorption film,and the effect of mannich acid hydrochloric acid corrosion inhibitor was suppressed.The corrosion products of PO43-and Fe3 ＋formed a layer of dense membrane on the steel surface,making the adsorption film formed by the corrosion inhibitor more dense,leading to difficulty in the contact of corrosive medium and metal surface,meanwhile,the diffusion resistance of ions or dissolved oxygen was increased,and the performance of mannich base hydrochloric acid corrosion inhibitor was promoted.
出处
《表面技术》
EI
CAS
CSCD
北大核心
2015年第9期102-107,115,共7页
Surface Technology
基金
西安石油大学全日制硕士研究生创新基金资助(2014cx130739)~~
关键词
曼尼希碱
SO2-4
PO3-4
极化曲线
缓蚀性能
Mannich base
SO_4^（2-）
PO_4^（3-）
polarization curve
corrosion inhibition performance
作者简介
王甜甜（1990-），女，陕西人，硕士研究生，主要研究方向为油气田化学品合成与应用。
通讯作者：李谦定（1959-），男，陕西人，教授，主要研究方向为从事油气田应用化学。
