高效咪唑-席夫缓蚀剂对P110在HCl溶液中的缓蚀机理分析  

Mechanism Analysis of Highly Effective Imidazole-Schiff Corrosion Inhibitor on P110 in HCl Solution

作　　者：刘文超 王鹏杰 汤梓杰 李浩[1,2] 王明安[3] 刘婉颖 林元华 LIU Wenchao;WANG Pengjie;TANG Zijie;LI Hao;WANG Mingan;LIU Wanying;LIN Yuanhua(State Key Laboratory of Oil and Gas Reservoir Geology and Development Engineering,Southwest Petroleum University,Chengdu 610500,China;School of New Energy and Materials,Southwest Petroleum University,Chengdu 610500,China;Chongqing Xintai Machinery Co.,Ltd.,Chongqing 402160,China)

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500 [2]西南石油大学新能源与材料学院,四川成都610500 [3]重庆新泰机械有限公司,重庆402160

出　　处：《材料保护》2025年第3期87-97,共11页Materials Protection

基　　金：国家自然科学基金(52074232);四川省自然科学基金重点项目(2022NSFSC0028)。

摘　　要：为了抑制油田酸化过程对管线钢的腐蚀,合成了一种咪唑-席夫缓蚀剂(IAP),通过失重与电化学试验,研究了不同浓度的IAP缓蚀剂在15%HCl溶液中对P110钢的缓蚀性能及缓蚀机理,并通过傅里叶红外光谱(FTIR)、扫描电镜(SEM)+能谱仪(EDS)和X射线光电子能谱(XPS)进一步证实IAP在15%HCl中对P110钢的缓蚀机理,此外,通过理论计算从分子水平进一步阐明了缓蚀机理合理性。结果表明,IAP添加浓度为400.0 mg/L时,在15%HCl中对P110钢的失重试验缓蚀效率为97.58%,交流阻抗谱(EIS)、动电位极化(Tafel)曲线测试结果表明缓蚀效率分别为97.32%、96.76%,EIS测试结果证明了IAP在P110钢表面成膜从而发挥缓蚀作用,Tafel曲线测试结果证明了IAP是以抑制阳极为主的混合型缓蚀剂。IAP对P110钢的吸附遵循Langmuir等温吸附方程并可自发吸附在P110钢表面。FTIR、SEM+EDS和XPS均能在P110钢表面检测到IAP所形成的保护膜。密度泛函理论(DFT)和分子动力学(MD)证明IAP的活性位点为苯环和咪唑环,苯环可接受Fe表面多余的电子,咪唑环上N的孤电子对与Fe形成稳定的配位键,MD可进一步证明IAP可自发吸附在Fe表面。IAP缓蚀剂能够在15%HCl的腐蚀介质中发挥优异的缓蚀性能,其机理是在P110钢表面形成稳定的保护膜。In order to inhibit the corrosion of pipeline steel during oilfield acidification,an imidazole-Schiff corrosion inhibitor(IAP)was syn-thesized.The corrosion inhibition performance and mechanism of IAP corrosion inhibitor with different concentration on P110 steel in 15%HCl solution were studied through weight loss and electrochemical tests.Subsequently,Fourier infrared spectroscopy(FTIR),scanning electron microscopy(SEM)+energy dispersive spectrometer(EDS)and X-ray photoelectron spectroscopy(XPS)were used to further confirm the inhibition mechanism of IAP on P110 steel in 15%HCl.In addition,the rationality of inhibition mechanism was further clarified from the molecular level by theoretical calculation.Results showed that when IAP added concentration was 400.0 mg/L,the weight loss test corrosion inhibition curve showed that the corrosion inhibition efficiencies were 97.32%and 96.76%,respectively.EIS test results proved that IAP played a role in corrosion inhibition by forming film on the surface of P110 steel,and Tafel curve test results proved that IAP was a mixed corrosion inhibitor mainly based on anode inhibition.Meanwhile,the adsorption of IAP on P110 steel followed Langmuir isothermal adsorption equation and could be spontaneously adsorbed on the surface of P110 steel.FTIR,SEM+EDS,and XPS successfully detected the protective film formed by IAP on the surface of P110 steel.Density functional theory(DFT)and molecular dynamics(MD)proved that the active sites of IAP were benzene ring and imidazole ring.Specifically,the benzene ring could accept excess electrons on the surface of Fe,the lone electron pair of N on the imidazole ring formed a stable coordination bond with Fe,and MD could further proved that IAP were spontaneously adsorbed on the surface of Fe.Overall,IAP corrosion inhibitor could demonstrate excellent corrosion inhibition performance in 15%HCl corrosive medium,with its mechanism involving the formation of a stable protective film on the surface of P110 steel.

关 键 词：咪唑-席夫缓蚀剂 金属腐蚀 电化学 密度泛函理论(DFT) 分子动力学 

分 类 号：TG174.42[金属学及工艺—金属表面处理]