表面技术2025，Vol.54Issue(12)：49-60,12.DOI:10.16490/j.cnki.issn.1001-3660.2025.12.004
氨基酸型缓蚀剂对碳钢CO2腐蚀的缓蚀性能分析
Analysis of Inhibition Properties of Amino Acid Corrosion Inhibitor on CO2 Corrosion of Carbon Steel
摘要
Abstract
The work aims to investigate the corrosion inhibition properties of two bio-based amino acid-derived inhibitors,N-octylglycine sodium(OCT)and N-dodecylglycine sodium(DOD),on N80 carbon steel in CO2-saturated brine environments.The two inhibitors with C8 and C12 alkyl chains were synthesized.The structures of the inhibitors were characterized with Fourier-transform infrared spectroscopy(FTIR)and nuclear magnetic resonance(NMR)spectroscopy.The corrosion inhibition properties of OCT and DOD were evaluated through electrochemical tests of electrochemical impedance spectroscopy(EIS)and potentiodynamic polarization curves(PDP),weight loss measurements,surface analysis techniques,and quantum chemical calculations.The FTIR spectra exhibited characteristic absorption peaks corresponding to the functional groups present in both inhibitors,indicating the successful incorporation of the desired chemical structures.NMR spectra provided further information on the molecular structure,confirming the presence of alkyl groups and amino acid functional groups,which supported the successful synthesis of the inhibitors.These results verified that the OCT and DOD inhibitors were synthesized with the intended molecular structures,confirming their potential as effective corrosion inhibitors.The corrosion inhibition properties characterized through weight loss measurements and electrochemical techniques showed that OCT and DOD enhanced the corrosion resistance of N80 carbon steel in CO2-saturated brine.The inhibition efficiency increased with the concentration of the inhibitors,reaching over 94％at 100 mg/L of DOD.EIS results showed that the capacitive arc radius increased with the concentration and carbon chain length of the amino acid-based inhibitors.The potentiodynamic polarization curves indicated that the amino acid-based inhibitors behaved as mixed-type inhibitors in the test environment,with the corrosion current density significantly decreasing as the inhibitor concentration and carbon chain length increased.The trends in inhibition efficiency obtained from both the weight loss method and electrochemical tests were consistent.Scanning electron microscopy(SEM)images showed that the corrosion on the N80 carbon steel surface was significantly reduced after the addition of the DOD inhibitor.The surface appeared smooth and flat,with clear grinding marks visible.This result demonstrated that the amino acid-based inhibitor with a C12 carbon chain provided superior corrosion protection compared to those with C8 carbon chain lengths.In addition,X-ray photoelectron spectroscopy(XPS)analysis confirmed that both OCT and DOD inhibitors formed a protective film on the surface of N80 carbon steel through chemisorption.This protective film served as a barrier,preventing further corrosion and protecting the steel surface from degradation,thereby effectively slowing the corrosion process.Quantum chemical calculations showed that the energy gap between the highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)of DOD was less than that of OCT,suggesting that DOD has a higher electron transfer capability.DOD formed a more effective adsorption layer on the surface of N80 carbon steel,leading to a significant reduction in the corrosion rate.The results indicated that DOD with a longer alkyl chain exhibited a higher electron-donating capacity.This enhanced electron donation not only strengthened its adsorption on the steel surface but also facilitated the formation of a more stable and protective film.In conclusion,DOD demonstrates superior corrosion inhibition compared to OCT.DOD with a C12 chain forms a more effective adsorbed film onto the steel surface,which gives higher corrosion resistance.Therefore,cytosine amino acid-based corrosion inhibitors with longer alkyl chains give better performance in CO2-saturated brine environments.关键词
N80碳钢/CO2腐蚀/缓蚀剂/电化学/量子化学计算Key words
N80 carbon steel/CO2 corrosion/corrosion inhibitor/electrochemistry/quantum chemical computation分类
矿业与冶金引用本文复制引用
闫坤凤,杨江,赵晓龙,马舒樊,王业飞,杨振..氨基酸型缓蚀剂对碳钢CO2腐蚀的缓蚀性能分析[J].表面技术,2025,54(12):49-60,12.基金项目
国家自然科学基金面上项目(52074339) （52074339）
辽宁省"兴辽英才计划"项目(XLYC1902053)General Project of National Natural Science Foundation of China(52074339) （XLYC1902053）
Liaoning Province"Xingliao Talents Plan"Project(XLYC1902053) （XLYC1902053）
