摘要：

通过阻垢率和缓蚀效率测试考察了三聚吡啶双效药剂的缓蚀、阻垢性能，运用电化学测试技术，结合密度泛函理论和分子动力学模拟计算，探讨了其缓蚀和阻垢机理。结果表明，在油田模拟水溶液中，该药剂对碳钢的缓蚀效率高达79.32%，对CaCO₃的阻垢效率为93.47%。随着药剂浓度的增大，自腐蚀电位不断正移，极化电阻R _P逐渐增大，自腐蚀电流密度显著降低，三聚吡啶的缓蚀作用机理为“几何覆盖效应型”缓蚀剂，其中阳极吸附阻滞作用更为明显。三聚吡啶分子结构中的吡啶环和Br原子位置的LUMO和HOMO轨道较强，其为三聚吡啶分子与Ca²⁺螯合阻垢和碳钢表面吸附缓蚀的活性位点；烷基链长对APMC分子与真空中Ca²⁺的螯合强度不具有显著影响，但随着烷基链长增大，其与Ca²⁺的螯合阻垢倾向降低，与Fe（110）表面的吸附缓蚀倾向显著增大。

关键词: 三聚吡啶双效药剂, 电化学测试技术, 密度泛函理论, 分子动力学, 缓蚀阻垢机理

Abstract:

The corrosion and scale inhibition performance of bi-functional agent were evaluated by measuring anti-scale effectiveness and corrosion inhibition efficiency. The corrosion inhibition and scale inhibition mechanism of the agent was discussed by electrochemical technology，density functional theory and molecular dynamics simulation calculations. The results showed that its corrosion inhibition efficiency was as high as 79.32% for carbon steel，and the scale inhibition efficiency for CaCO₃ was 93.47%. With the increase of the doseage，the self corrosion potential kept moving positively，the polarization resistance R _P increased gradually，and the self corrosion current density decreased significantly. The inhibition mechanism of tripyridine was “geometric coverage effect”，in which the anodic adsorption retardation was more obvious. The LUMO and HOMO orbitals were mainly located around pyridine ring and Br atoms，which were the active sites for its chelating effect with Ca²⁺ and corrosion inhibition effect by adsorbing onto carbon steel surface. The alkyl chain length had no significant effect on the chelating strength of APMC with Ca²⁺. However，with the increase of alkyl chain length，the chelating effect and anti-scale tendency decreased，while the corrosion inhibition tendency by APMC’s adsorption onto Fe（110） increased significantly.

Key words: trimeric pyrdinium, electrochemical testing technology, density functional theory, molecular dynamics, corrosion and scale inhibition mechanism

中图分类号: 

• X703.1